Do sperm and lubricants gel well with each other? A systematic review

Vaginal lubricants are commonly used to aid sexual pleasure and/or to help combat vaginal dryness and dyspareunia. Several studies have reported their impact on sperm function, however there are no published guidelines to help healthcare professionals and couples select a vaginal lubricant that is 'sperm-safe'. To address this, we conducted a literature search using both PubMed and Scopus to identify and appraise manuscripts that reported the impact of lubricants on sperm function. We did not restrict the literature search by year of publication, and we only included manuscripts that looked at the impact of vaginal lubricants on human sperm. The quality of the eligible studies was assessed using the Björndahl et al., (2016) checklist for semen analysis, as most of the studies reported the findings of a basic semen analysis. A total of 24 articles were eligible for analysis with a total of 35 vaginal lubricants (that were available to buy over the counter) being included, 2 of which studied the effect of vaginal lubricants on sperm function in vivo, and 22 being conducted in vitro. KY Jelly, PreSeed and Astroglide were most studied, with most manuscripts focussing on their impact on sperm motility. A paucity of data on most lubricants combined with methodological variations between studies and limited/no reporting on pregnancy outcomes means greater efforts are required before an evidence-based guideline can be published.

Proteomic analysis reveals a potential role for extracellular vesicles within the erythroblastic island niche

Introduction: Erythroblastic island (EBI) macrophages play an essential role in the production and maturation of the vast numbers of red blood cells (RBCs) that are produced throughout life. Their location within the bone marrow makes it difficult to study the cellular and molecular interactions associated with their action so we have used an in vitro model of the EBI niche using macrophages derived from human induced pluripotent stem cells (hiPSCs). We previously demonstrated that the activation of the transcription factor KLF1 enhanced the activity of hiPSC-derived EBI macrophages. Methods: To elucidate the mechanisms associated with EBI-like activity we carried out a quantitative proteomic analysis and assessed the role of extracellular vesicles using Nanosight Tracking analyses and media filtration. Results and Discussion: Gene ontology analysis showed that many of the proteins upregulated by KLF1 were protein-binding factors, some of which were associated with the cell membrane or extracellular vesicles We demonstrated that filtration of macrophage-conditioned media resulted in a reduction in the supportive effects on erythroid cell viability and maturation implying a role for extracellular vesicles but this was not KLF1 dependent. Pathway analyses of the proteomic data revealed that proteins upregulated by KLF1 were associated with the citric acid cycle, pyruvate metabolism and ATP synthesis indicating that KLF1-activated macrophages had a metabolic profile comparable to a pro-reparative phenotype. This study has generated a proteomic dataset that could provide new insights into the role of macrophages within the EBI niche and has indicated a potential role for extracellular vesicles in the differentiation and maturation of RBCs in vitro. Further research will aid in the production of RBCs in vitro for use in disease modelling and cell therapy.

A 20-year overview of fertility preservation in boys: new insights gained through a comprehensive international survey

STUDY QUESTION

Twenty years after the inception of the first fertility preservation programme for pre-pubertal boys, what are the current international practices with regard to cryopreservation of immature testicular tissue?

SUMMARY ANSWER

Worldwide, testicular tissue has been cryopreserved from over 3000 boys under the age of 18 years for a variety of malignant and non-malignant indications; there is variability in practices related to eligibility, clinical assessment, storage, and funding.

WHAT IS KNOWN ALREADY

For male patients receiving gonadotoxic treatment prior to puberty, testicular tissue cryopreservation may provide a method of fertility preservation. While this technique remains experimental, an increasing number of centres worldwide are cryopreserving immature testicular tissue and are approaching clinical application of methods to use this stored tissue to restore fertility. As such, standards for quality assurance and clinical care in preserving immature testicular tissue should be established.

STUDY DESIGN SIZE DURATION

A detailed survey was sent to 17 centres within the recently established ORCHID-NET consortium, which offer testicular tissue cryopreservation to patients under the age of 18 years. The study encompassed 60 questions and remained open from 1 July to 1 November 2022.

PARTICIPANTS/MATERIALS SETTING METHODS

Of the 17 invited centres, 16 completed the survey, with representation from Europe, Australia, and the USA. Collectively, these centres have cryopreserved testicular tissue from patients under the age of 18 years. Data are presented using descriptive analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Since the establishment of the first formal fertility preservation programme for pre-pubertal males in 2002, these 16 centres have cryopreserved tissue from 3118 patients under the age of 18 years, with both malignant (60.4%) and non-malignant (39.6%) diagnoses. All centres perform unilateral biopsies, while 6/16 sometimes perform bilateral biopsies. When cryopreserving tissue, 9/16 centres preserve fragments sized ≤5 mm3 with the remainder preserving fragments sized 6-20 mm3. Dimethylsulphoxide is commonly used as a cryoprotectant, with medium supplements varying across centres. There are variations in funding source, storage duration, and follow-up practice. Research, with consent, is conducted on stored tissue in 13/16 centres.

LIMITATIONS REASONS FOR CAUTION

While this is a multi-national study, it will not encompass every centre worldwide that is cryopreserving testicular tissue from males under 18 years of age. As such, it is likely that the actual number of patients is even higher than we report. Whilst the study is likely to reflect global practice overall, it will not provide a complete picture of practices in every centre.

WIDER IMPLICATIONS OF THE FINDINGS

Given the research advances, it is reasonable to suggest that cryopreserved immature testicular tissue will in the future be used clinically to restore fertility. The growing number of patients undergoing this procedure necessitates collaboration between centres to better harmonize clinical and research protocols evaluating tissue function and clinical outcomes in these patients.

STUDY FUNDING/COMPETING INTERESTS

K.D. is supported by a CRUK grant (C157/A25193). R.T.M. is supported by an UK Research and Innovation (UKRI) Future Leaders Fellowship (MR/S017151/1). The MRC Centre for Reproductive Health at the University of Edinburgh is supported by MRC (MR/N022556/1). C.L.M. is funded by Kika86 and ZonMW TAS 116003002. A.M.M.v.P. is supported by ZonMW TAS 116003002. E.G. was supported by the Research Program of the Research Foundation-Flanders (G.0109.18N), Kom op tegen Kanker, the Strategic Research Program (VUB_SRP89), and the Scientific Fund Willy Gepts. J.-B.S. is supported by the Swedish Childhood Cancer Foundation (TJ2020-0026). The work of NORDFERTIL is supported by the Swedish Childhood Cancer Foundation (PR2019-0123; PR2022-0115), the Swedish Research Council (2018-03094; 2021-02107), and the Birgitta and Carl-Axel Rydbeck's Research Grant for Paediatric Research (2020-00348; 2021-00073; 2022-00317; 2023-00353). C.E is supported by the Health Department of the Basque Government (Grants 2019111068 and 2022111067) and Inocente Inocente Foundation (FII22/001). M.P.R. is funded by a Medical Research Council Centre for Reproductive Health Grant No: MR/N022556/1. A.F. and N.R. received support from a French national research grant PHRC No. 2008/071/HP obtained by the French Institute of Cancer and the French Healthcare Organization. K.E.O. is funded by the University of Pittsburgh Medical Center and the US National Institutes of Health HD100197. V.B-L is supported by the French National Institute of Cancer (Grant Seq21-026). Y.J. is supported by the Royal Children's Hospital Foundation and a Medical Research Future Fund MRFAR000308. E.G., N.N., S.S., C.L.M., A.M.M.v.P., C.E., R.T.M., K.D., M.P.R. are members of COST Action CA20119 (ANDRONET) supported by COST (European Cooperation in Science and Technology). The Danish Child Cancer Foundation is also thanked for financial support (C.Y.A.). The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

N/A.

Efficacy of virtual reality for pain relief in medical procedures: a systematic review and meta-analysis

BACKGROUND

Effective pain control is crucial to optimise the success of medical procedures. Immersive virtual reality (VR) technology could offer an effective non-invasive, non-pharmacological option to distract patients and reduce their experience of pain. We aimed to evaluate the efficacy of Immersive virtual reality (VR) technology in reducing patient's pain perception during various medical procedures by conducting a systematic review and meta-analysis.

METHODS

We searched MEDLINE, EMBASE, CENTRAL, CINAHL, and SIGLE until December 2022 for all randomised clinical trials (RCT) evaluating any type of VR in patients undergoing any medical procedure. We conducted a random effect meta-analysis summarising standardised mean differences (SMD) with 95% confidence intervals (CI). We evaluated heterogeneity using I 2 and explored it using subgroup and meta-regression analyses.

RESULTS

In total, we included 92 RCTs (n = 7133 participants). There was a significant reduction in pain scores with VR across all medical procedures (n = 83, SMD - 0.78, 95% CI - 1.00 to - 0.57, I 2 = 93%, p = < 0.01). Subgroup analysis showed varied reduction in pain scores across trial designs [crossover (n = 13, SMD - 0.86, 95% CI - 1.23 to - 0.49, I 2 = 72%, p = < 0.01) vs parallel RCTs (n = 70, SMD - 0.77, 95% CI - 1.01 to - 0.52, I 2 = 90%, p = < 0.01)]; participant age groups [paediatric (n = 43, SMD - 0.91, 95% CI - 1.26 to - 0.56, I 2 = 87%, p = < 0.01) vs adults (n = 40, SMD - 0.66, 95% CI - 0.94 to - 0.39, I 2 = 89%, p = < 0.01)] or procedures [venepuncture (n = 32, SMD - 0.99, 95% CI - 1.52 to - 0.46, I 2 = 90%, p = < 0.01) vs childbirth (n = 7, SMD - 0.99, 95% CI - 1.59 to - 0.38, I 2 = 88%, p = < 0.01) vs minimally invasive medical procedures (n = 25, SMD - 0.51, 95% CI - 0.79 to - 0.23, I 2 = 85%, p = < 0.01) vs dressing changes in burn patients (n = 19, SMD - 0.8, 95% CI - 1.16 to - 0.45, I 2 = 87%, p = < 0.01)]. We explored heterogeneity using meta-regression which showed no significant impact of different covariates including crossover trials (p = 0.53), minimally invasive procedures (p = 0.37), and among paediatric participants (p = 0.27). Cumulative meta-analysis showed no change in overall effect estimates with the additional RCTs since 2018.

CONCLUSIONS

Immersive VR technology offers effective pain control across various medical procedures, albeit statistical heterogeneity. Further research is needed to inform the safe adoption of this technology across different medical disciplines.

Diagnosis and management of endometrial hyperplasia: A UK national audit of adherence to national guidance 2012-2020

BACKGROUND

Endometrial hyperplasia (EH) is a precusor lesion for endometrial cancer (EC), the commonest gynaecological malignancy in high-income countries. EH is a proliferation of glandular tissue, classified as either non-atypical endometrial hyperplasia (NEH) or, if the cytological features are abnormal, atypical endometrial hyperplasia (AEH). The clinical significance of AEH is that patients face both a high risk of having occult EC and a high risk of progression to EC if untreated. Recommendations on the care of women with EH were introduced by United Kingdom-wide guidance (Green-top Guide No. 67, 2016). National adherence to guidance is unknown. We aimed to describe the care of patients with EH; to compare the patterns of care for those with EH with national guidance to identify opportunities for quality improvement; and to compare patterns of care prior to and following the introduction of national guidance to understand its impact.

METHODS AND FINDINGS

In this UK-wide patient-level clinical audit, we included 3,307 women who received a new histological diagnosis of EH through a gynaecology service between 1 January 2012 and 30 June 2020. We described first-line management, management at 2 years, and surgical characteristics prior to and following national guidance for EH using proportions and 95% confidence intervals (CIs) and compared process measures between time periods using multilevel Poisson regression. Of the 3,307 patients, 1,570 had NEH and 1,511 had AEH between 2012 and 2019. An additional 85 patients had NEH and 141 had AEH during 2020. Prior to national guidance, 9% (95% CI [6%, 15%]) received no initial treatment for NEH compared with 3% (95% CI [1%, 5%]) post-guidance; 31% (95% CI [26%, 36%]) and 48% (95% CI [43% 53%]) received an intrauterine progestogen, respectively, in the same periods. The predominant management of women with AEH did not differ, with 68% (95% CI [61%, 74%]) and 67% (95 CI [63%, 71%]) receiving first-line hysterectomy, respectively. By 2 years, follow-up to histological regression without hysterectomy increased from 38% (95% CI [33%, 43%]) to 52% (95% CI [47%, 58%]) for those with NEH (rate ratio (RR) 1.38, 95% CI [1.18, 1.63] p < 0.001). We observed an increase in the use of total laparoscopic hysterectomy among those with AEH (RR 1.26, 95% CI [1.04, 1.52]). In the later period, 37% (95% CI [29%, 44%]) of women initially diagnosed with AEH who underwent a first-line hysterectomy, received an upgraded diagnosis of EC. Study limitations included retrospective data collection from routine clinical documentation and the inability to comprehensively understand the shared decision-making process where care differed from guidance.

CONCLUSIONS

The care of patients with EH has changed in accordance with national guidance. More women received first-line medical management of NEH and were followed up to histological regression. The follow-up of those with AEH who do not undergo hysterectomy must be improved, given their very high risk of coexistent cancer and high risk of developing cancer.

Extracellular vesicles arising from apoptosis: forms, functions, and applications

Extracellular vesicles (EVs) are lipid bilayer-enclosed subcellular bodies produced by most, if not all cells. Research over the last two decades has recognised the importance of EVs in intercellular communication and horizontal transfer of biological material. EVs range in diameter from tens of nanometres up to several micrometres and are able to transfer a spectrum of biologically active cargoes - from whole organelles, through macromolecules including nucleic acids and proteins, to metabolites and small molecules - from their cells of origin to recipient cells, which may consequently become physiologically or pathologically altered. Based on their modes of biogenesis, the most renowned EV classes are (1) microvesicles, (2) exosomes (both produced by healthy cells), and (3) EVs from cells undergoing regulated death by apoptosis (ApoEVs). Microvesicles bud directly from the plasma membrane, while exosomes are derived from endosomal compartments. Current knowledge of the formation and functional properties of ApoEVs lags behind that of microvesicles and exosomes, but burgeoning evidence indicates that ApoEVs carry manifold cargoes, including mitochondria, ribosomes, DNA, RNAs, and proteins, and perform diverse functions in health and disease. Here we review this evidence, which demonstrates substantial diversity in the luminal and surface membrane cargoes of ApoEVs, permitted by their very broad size range (from around 50 nm to >5 μm; the larger often termed apoptotic bodies), strongly suggests their origins through both microvesicle- and exosome-like biogenesis pathways, and indicates routes through which they interact with recipient cells. We discuss the capacity of ApoEVs to recycle cargoes and modulate inflammatory, immunological, and cell fate programmes in normal physiology and in pathological scenarios such as cancer and atherosclerosis. Finally, we provide a perspective on clinical applications of ApoEVs in diagnostics and therapeutics. © 2023 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.

The risk of miscarriage following COVID-19 vaccination: a systematic review and meta-analysis

STUDY QUESTION

What is the risk of miscarriage among pregnant women who received any of the COVID-19 vaccines?

SUMMARY ANSWER

There is no evidence that COVID-19 vaccines are associated with an increased risk of miscarriage.

WHAT IS KNOWN ALREADY

In response to the COVID-19 pandemic, the mass roll-out of vaccines helped to boost herd immunity and reduced hospital admissions, morbidity, and mortality. Still, many were concerned about the safety of vaccines for pregnancy, which may have limited their uptake among pregnant women and those planning a pregnancy.

STUDY DESIGN, SIZE, DURATION

For this systematic review and meta-analysis, we searched MEDLINE, EMBASE, and Cochrane CENTRAL from inception until June 2022 using a combination of keywords and MeSH terms.

PARTICIPANTS/MATERIALS, SETTING, METHODS

We included observational and interventional studies that enrolled pregnant women and evaluated any of the available COVID-19 vaccines compared to placebo or no vaccination. We primarily reported on miscarriage in addition to ongoing pregnancy and/or live birth.

MAIN RESULTS AND THE ROLE OF CHANCE

We included data from 21 studies (5 randomized trials and 16 observational studies) reporting on 149 685 women. The pooled rate of miscarriage among women who received a COVID-19 vaccine was 9% (n = 14 749/123 185, 95% CI 0.05-0.14). Compared to those who received a placebo or no vaccination, women who received a COVID-19 vaccine did not have a higher risk of miscarriage (risk ratio (RR) 1.07, 95% CI 0.89-1.28, I2 35.8%) and had comparable rates for ongoing pregnancy or live birth (RR 1.00, 95% CI 0.97-1.03, I2 10.72%).

LIMITATIONS, REASONS FOR CAUTION

Our analysis was limited to observational evidence with varied reporting, high heterogeneity and risk of bias across included studies, which may limit the generalizability and confidence in our findings.

WIDER IMPLICATIONS OF THE FINDINGS

COVID-19 vaccines are not associated with an increase in the risk of miscarriage or reduced rates of ongoing pregnancy or live birth among women of reproductive age. The current evidence remains limited and larger population studies are needed to further evaluate the effectiveness and safety of COVID-19 vaccination in pregnancy.

STUDY FUNDING/COMPETING INTEREST(S)

No direct funding was provided to support this work. M.P.R. was funded by the Medical Research Council Centre for Reproductive Health Grant No: MR/N022556/1. B.H.A.W. hold a personal development award from the National Institute of Health Research in the UK. All authors declare no conflict of interest.

REGISTRATION NUMBER

CRD42021289098.

Granulocyte-colony stimulating factor does not prevent in vitro cisplatin-induced germ cell reduction in immature human and mouse testis

BACKGROUND

Currently there are no established fertility preservation options for pre-pubertal boys facing cancer treatment. Granulocyte-colony stimulating factor (G-CSF) treatment has been proposed to be chemoprotective against spermatogonial cell loss in an alkylating chemotherapy model of busulfan treated adult mice. Having previously shown that exposure to the alkylating-like chemotherapy cisplatin resulted in a reduction in germ cell numbers in immature human testicular tissues, we here investigate whether G-CSF would prevent cisplatin-induced germ cell loss in immature human and mouse (fetal and pre-pubertal) testicular tissues.

METHODS

Organotypic in vitro culture systems were utilised to determine the effects of clinically-relevant concentrations of G-CSF in cisplatin-exposed immature testicular tissues. Human fetal (n = 14 fetuses) and mouse pre-pubertal (n = 4 litters) testicular tissue pieces were cultured and exposed to cisplatin or vehicle control for 24 hrs and analysed at 72 and 240 hrs post-exposure. Combined G-CSF and cisplatin exposure groups explored varying concentrations and duration of G-CSF supplementation to the culture medium (including groups receiving G-CSF before, during and after cisplatin exposure). In addition, effects of G-CSF supplementation alone were investigated. Survival of total germ cell and sub-populations were identified by expression of AP2γ and MAGE-A4 for human gonocytes and (pre)spermatogonia, respectively, and MVH and PLZF, for mouse germ cells and putative spermatogonial stem cells (SSCs) respectively, were quantified.

RESULTS

Exposure to cisplatin resulted in a reduced germ cell number in human fetal and mouse pre-pubertal testicular tissues at 240 hrs post-exposure. Germ cell number was not preserved by combined exposure with G-CSF using any of the exposure regimens (prior to, during or after cisplatin exposure). Continuous supplementation with G-CSF alone for 14 days did not change the germ cell composition in either human or mouse immature testicular tissues.

CONCLUSIONS

This study demonstrates that exposure to G-CSF does not prevent cisplatin-induced germ cell loss in immature human and mouse testicular tissues in an in vitro system.

Impact of taxane-based chemotherapeutics on male reproductive function

Lay Summary of Letter Men and boys with cancer treated with chemotherapy are known to have reduced fertility following their treatment. This is because some chemotherapy drugs can damage the cells in the testicles that make sperm. This study found there is limited information available on the effect of one group of chemotherapy drugs, called taxanes, on testicular function and fertility. More studies are needed to aid clinicians in advising patients on how this taxane-based chemotherapy may affect their future fertility.

Cisplatin Effects on the Human Fetal Testis - Establishing the Sensitive Period for (Pre)Spermatogonial Loss and Relevance for Fertility Preservation in Pre-Pubertal Boys

Background

Exposure to chemotherapy during childhood can impair future fertility. Studies using in vitro culture have shown exposure to platinum-based alkylating-like chemotherapy reduces the germ cell number in the human fetal testicular tissues. We aimed to determine whether effects of exposure to cisplatin on the germ cell sub-populations are dependent on the gestational age of the fetus and what impact this might have on the utility of using human fetal testis cultures to model chemotherapy exposure in childhood testis.

Methods

We utilised an in vitro culture system to culture pieces of human fetal testicular tissues (total n=23 fetuses) from three different gestational age groups (14-16 (early), 17-19 (mid) and 20-22 (late) gestational weeks; GW) of the second trimester. Tissues were exposed to cisplatin or vehicle control for 24 hours, analysing the tissues 72 and 240 hours post-exposure. Number of germ cells and their sub-populations, including gonocytes and (pre)spermatogonia, were quantified.

Results

Total germ cell number and number of both germ cell sub-populations were unchanged at 72 hours post-exposure to cisplatin in the testicular tissues from fetuses of the early (14-16 GW) and late (20-22 GW) second trimester. In the testicular tissues from fetuses of mid (17-19 GW) second trimester, total germ cell and gonocyte number were significantly reduced, whilst (pre)spermatogonial number was unchanged. At 240 hours post-exposure, the total number of germ cells and that of both sub-populations was significantly reduced in the testicular tissues from fetuses of mid- and late-second trimester, whilst germ cells in early-second trimester tissues were unchanged at this time-point.

Conclusions

In vitro culture of human fetal testicular tissues can be a useful model system to investigate the effects of chemotherapy-exposure on germ cell sub-populations during pre-puberty. Interpretation of the results of such studies in terms of relevance to later (infant and pre-pubertal) developmental stages should take into account the changes in germ cell composition and periods of germ cell sensitivity in the human fetal testis.

Worth the paper it's written on? A cross-sectional study of Medical Certificate of Stillbirth accuracy in the UK

BACKGROUND

The Medical Certificate of Stillbirth (MCS) records data about a baby's death after 24 weeks of gestation but before birth. Major errors that could alter interpretation of the MCS were widespread in two UK-based regional studies.

METHODS

A multicentre evaluation was conducted, examining MCS issued 1 January 2018 to 31 December 2018 in 76 UK obstetric units. A systematic case-note review of stillbirths was conducted by Obstetric and Gynaecology trainees, generating individual 'ideal MCSs' and comparing these to the actual MCS issued. Anonymized central data analysis described rates and types of error, agreement and factors associated with major errors.

RESULTS

There were 1120 MCSs suitable for assessment, with 126 additional submitted data sets unsuitable for accuracy analysis (total 1246 cases). Gestational age demonstrated 'substantial' agreement [K = 0.73 (95% CI 0.70-0.76)]. Primary cause of death (COD) showed 'fair' agreement [K = 0.26 (95% CI 0.24-0.29)]. Major errors [696/1120; 62.1% (95% CI 59.3-64.9%)] included certificates issued for fetal demise at <24 weeks' gestation [23/696; 3.3% (95% CI 2.2-4.9%)] or neonatal death [2/696; 0.3% (95% CI 0.1-1.1%)] or incorrect primary COD [667/696; 95.8% (95% CI 94.1-97.1%)]. Of 540/1246 [43.3% (95% CI 40.6-46.1%)] 'unexplained' stillbirths, only 119/540 [22.0% (95% CI 18.8-25.7%)] remained unexplained; the majority were redesignated as either fetal growth restriction [FGR: 195/540; 36.1% (95% CI 32.2-40.3%)] or placental insufficiency [184/540; 34.1% (95% CI 30.2-38.2)]. Overall, FGR [306/1246; 24.6% (95% CI 22.3-27.0%)] was the leading primary COD after review, yet only 53/306 [17.3% (95% CI 13.5-22.1%)] FGR cases were originally attributed correctly.

CONCLUSION

This study demonstrates widespread major errors in MCS completion across the UK. MCS should only be completed following structured case-note review, with particular attention on the fetal growth trajectory.

Protocol for developing a core outcome set for male infertility research: an international consensus development study

STUDY QUESTION

We aim to develop, disseminate and implement a minimum data set, known as a core outcome set, for future male infertility research.

WHAT IS KNOWN ALREADY

Research into male infertility can be challenging to design, conduct and report. Evidence from randomized trials can be difficult to interpret and of limited ability to inform clinical practice for numerous reasons. These may include complex issues, such as variation in outcome measures and outcome reporting bias, as well as failure to consider the perspectives of men and their partners with lived experience of fertility problems. Previously, the Core Outcome Measure for Infertility Trials (COMMIT) initiative, an international consortium of researchers, healthcare professionals and people with fertility problems, has developed a core outcome set for general infertility research. Now, a bespoke core outcome set for male infertility is required to address the unique challenges pertinent to male infertility research.

STUDY DESIGN SIZE DURATION

Stakeholders, including healthcare professionals, allied healthcare professionals, scientists, researchers and people with fertility problems, will be invited to participate. Formal consensus science methods will be used, including the modified Delphi method, modified Nominal Group Technique and the National Institutes of Health's consensus development conference.

PARTICIPANTS/MATERIALS SETTING METHODS

An international steering group, including the relevant stakeholders outlined above, has been established to guide the development of this core outcome set. Possible core outcomes will be identified by undertaking a systematic review of randomized controlled trials evaluating potential treatments for male factor infertility. These outcomes will be entered into a modified Delphi method. Repeated reflection and re-scoring should promote convergence towards consensus outcomes, which will be prioritized during a consensus development meeting to identify a final core outcome set. We will establish standardized definitions and recommend high-quality measurement instruments for individual core outcomes.

STUDY FUNDING/COMPETING INTERESTS

This work has been supported by the Urology Foundation small project award, 2021. C.L.R.B. is the recipient of a BMGF grant and received consultancy fees from Exscentia and Exceed sperm testing, paid to the University of Dundee and speaking fees or honoraria paid personally by Ferring, Copper Surgical and RBMO. S.B. received royalties from Cambridge University Press, Speaker honoraria for Obstetrical and Gynaecological Society of Singapore, Merk SMART Masterclass and Merk FERRING Forum, paid to the University of Aberdeen. Payment for leadership roles within NHS Grampian, previously paid to self, now paid to University of Aberdeen. An Honorarium is received as Editor in Chief of Human Reproduction Open. M.L.E. is an advisor to the companies Hannah and Ro. B.W.M. received an investigator grant from the NHMRC, No: GNT1176437 is a paid consultant for ObsEva and has received research funding from Ferring and Merck. R.R.H. received royalties from Elsevier for a book, consultancy fees from Glyciome, and presentation fees from GryNumber Health and Aytu Bioscience. Aytu Bioscience also funded MiOXYS systems and sensors. Attendance at Fertility 2020 and Roadshow South Africa by Ralf Henkel was funded by LogixX Pharma Ltd. R.R.H. is also Editor in Chief of Andrologia and has been an employee of LogixX Pharma Ltd. since 2020. M.S.K. is an associate editor with Human Reproduction Open. K.Mc.E. received an honoraria for lectures from Bayer and Pharmasure in 2019 and payment for an ESHRE grant review in 2019. His attendance at ESHRE 2019 and AUA 2019 was sponsored by Pharmasure and Bayer, respectively. The remaining authors declare no competing interests.

TRIAL REGISTRATION NUMBER

Core Outcome Measures in Effectiveness Trials (COMET) initiative registration No: 1586. Available at www.comet-initiative.org/Studies/Details/1586.

TRIAL REGISTRATION DATE

N/A.

DATE OF FIRST PATIENT’S ENROLMENT

N/A.

Outcome reporting across randomized controlled trials evaluating potential treatments for male infertility: a systematic review

STUDY QUESTION

What are the primary outcomes and outcome measures used in randomized controlled trials (RCTs) evaluating potential treatments for male infertility in the last 10 years?

SUMMARY ANSWER

Outcome reporting across male infertility trials is heterogeneous with numerous definitions and measures used to define similar outcomes.

WHAT IS KNOWN ALREADY

No core outcome set for male infertility trials has been developed. Male infertility trials are unique in that they have potentially three participants, a man, a female partner and their offspring and this will likely lead to significant variation in outcome reporting in randomized trials.

STUDY DESIGN SIZE DURATION

A systematic review of RCTs mapping outcomes and outcome measures evaluating potential treatments for men with infertility registered in the Cochrane Register of Controlled Trials (CENTRAL) between January 2010 and July 2021.

PARTICIPANTS/MATERIALS SETTING METHODS

Abstract screening and study selection was undertaken in duplicate using a review protocol that was developed prior to commencing the review. No risk of bias assessment was undertaken as this review aims to report on outcome reporting only.

MAIN RESULTS AND THE ROLE OF CHANCE

One hundred and seventy-five RCTs were identified, and given the large number of studies we limited our review to the 100 largest trials. Seventy-nine different treatments were reported across the 100 largest RCTs including vitamin and dietary supplements (18 trials), surgical treatments (18 trials) and sperm selection techniques (22 trials). When considering the largest 100 trials (range: 80-2772 participants), 36 primary and 89 secondary outcomes were reported. Forty-seven trials reported a primary outcome and 36 trials clearly defined their primary outcome. Pregnancy outcomes were inconsistently reported and included pregnancy rate (51 trials), pregnancy loss including miscarriage, ectopic pregnancy, stillbirth (9 trials) and live birth (13 trials). Trials consistently reporting the same outcome frequently used different definitions. For example, semen quality was reported by 75 trials and was defined in 7 different ways, including; the World Health Organization (WHO) 2010 criteria (32 trials), WHO 1999 criteria (18 trials), WHO 1992 criteria (3 trials), WHO 1999 and 1992 criteria (1 trial) and the Kruger strict morphology criteria (1 trial).

LIMITATIONS REASONS FOR CAUTION

We only evaluated the 100 largest trials published in the last 10 years and did not report outcomes on the remaining 75. An outcome was included as a primary outcome only if clearly stated in the manuscript and we did not contact authors to clarify this. As our review mapped outcomes and outcome measures, we did not undertake an integrity assessment of the trials included in our review.

WIDER IMPLICATIONS OF THE FINDINGS

Most randomized trials evaluating treatments for male infertility report different outcomes. Only half of the RCTs reported pregnancy rate and even fewer reported live birth; furthermore, the definitions of these outcomes varies across trials. Developing, disseminating and implementing a minimum data set, known as a core outcome set, for male infertility research could help to improve outcome selection, collection and reporting.

STUDY FUNDING/COMPETING INTERESTS

A.P.-chairman of external scientific advisory committee of Cryos International Denmark ApS, member of the scientific advisory board for Cytoswim LDT and ExSeed Health. Guest lecture at the 'Insights for Fertility Conference', funded by MERK SERONO Limited. M.v.W.-holds a ZON-MW research grant. No external funding was obtained for this study.

P–394 Intralipid infusion at time of embryo transfer in women with history of recurrent implantation failure: a systematic review and meta-analysis

Study question

What is the effectiveness of IV Intralipid (IVI) in improving pregnancy rates in women undergoing IVF with history of Recurrent implantation failure (RIF) to improve reproductive outcomes.

Summary answer

The evidence to support the use of IVI at the time of embryo transfer in women with RIF is limited. More RCTs are needed. What is known already: Optimising the implantation process following embryo transfer remains a clinical challenge with 10% of couples undergoing IVF affected by (RIF). Immunotherapy could help to optimise endometrial receptivity and increase the chances for successful conception in women with history of RIF. Intra-venous Intralipid (IVI), a fat-based emulsion of soybean oil, glycerine, phospholipids, egg, and polyunsaturated fatty acids, has been evaluated in several trials as a potential intervention to downregulate the uNK cells and macrophages as well as inhibit the pro-inflammatory mediators including T1 helper cells. Evidence synthesis is needed to evaluate the effectiveness of this intervention.

Study design, size, duration

We performed this systematic review using a prospectively registered protocol (CRD42019148517) and reported in accordance with the PRISMA guidelines. Participants/materials, setting, methods: We searched MEDLINE, EMBASE and CENTRAL for any randomised trials evaluating the use of IVI at the time of embryo transfer in women undergoing assisted conception until September 2020. We extracted data in duplicate and assessed risk of bias using the Cochrane Risk of Bias tools. We meta-analysed data using a random effect model and reported on dichotomous outcomes using risk ratio (RR) and 95% confidence interval (CI).

Main results and the role of chance

We included five randomised trials reporting on 843 women with an overall moderate risk of bias. All trials used 20% IVI solution at the time of embryo transfer compared to normal saline infusion or no intervention (routine care). The IVI group had a higher chance of clinical pregnancy (172 vs 119, RR 1.55, 95%CI 1.16–2.07, I2 44.2%) and live birth (132 vs 73, RR 1.83, 95%CI 1.42–2.35, I2 0%) post treatment compared to no intervention.

Limitations, reasons for caution

Our findings are limited by the small sample size and the variations in treatment protocols and population characteristics.

Wider implications of the findings: Our meta-analysis offers an overview on the value of IVI to help women affected by RIF. Given the limitations and the quality of included trials, adopting the use of IVI a-la-carte to couples undergoing IVF remains immature. IVI should not be offered until larger RCTs demonstrate a persistent benefit.

Trial registration number

CRD42019148517

Extracellular vesicles in urological malignancies

Extracellular vesicles (EVs) are small lipid bound structures released from cells containing bioactive cargoes. Both the type of cargo and amount loaded varies compared to that of the parent cell. The characterisation of EVs in cancers of the male urogenital tract has identified several cargoes with promising diagnostic and disease monitoring potential. EVs released by cancers of the male urogenital tract promote cell-to-cell communication, migration, cancer progression and manipulate the immune system promoting metastasis by evading the immune response. Their use as diagnostic biomarkers represents a new area of screening and disease detection, potentially reducing the need for invasive biopsies. Many validated EV cargoes have been found to have superior sensitivity and specificity than current diagnostic tools currently in use. The use of EVs to improve disease monitoring and develop novel therapeutics will enable clinicians to individualise patient management in the exciting era of personalised medicine.

The transformative impact of extracellular vesicles on developing sperm

Objective

To review the role of extracellular vesicles (EVs) released from the male reproductive tract and their impact on developing sperm. We discuss how sperm exiting the seminiferous tubules, although developmentally mature, require further modification. Acquisition of various functions including increased motility, transfer of cargoes and ability to undertake the acrosome reaction is mediated through the interaction between sperm and EVs.

Methods

A review of the literature identified that EVs are released from different portions of the male reproductive tract, notably the epididymis and prostate. These EVs interact with sperm as they pass from the seminiferous tubules to the epididymis and vas deferens prior to ejaculation.

Results

EVs are small lipid-bound particles carrying bespoke RNA, protein and lipid cargoes. These cargoes are loaded based on the state of the parent cell and are used to communicate with recipient cells. In sperm, these cargoes are essential for post-testicular modification.

Conclusions

Interactions between developing sperm and EVs are important for the subsequent function of sperm. Prior to ejaculation, these interactions confer important changes for the post-testicular modification and development of sperm. Little is known about the interaction between EVs from the testes and the spermatogonial stem cell niche or developing sperm within the seminiferous tubules. However, the numerous roles of EVs in the post-testicular modification of sperm have led many to suspect that they may also play important roles in developing sperm within the testes.

Lay summary

Sperm are crucial for successful fertility. In order to do this, they must be able to swim a large distance to meet the egg in the female reproductive tract and fertilise it. Once released from the testes, sperm may appear to be fully developed, but this is not the case. Several important modifications are required in order for them to swim and fertilise an egg. These modifications are carried out by sending sperm small packages from other cells which contain messages and cargo. We discuss the release of these small packages along with different parts of the male reproductive tract and how they change the way sperm behave and function. This article reviews the literature and known functions of these packages called extracellular vesicles, which are released by the male reproductive tract and modify sperm, transforming their function, before they are ejaculated.

P139 Women's Health Care during COVID-19

Introduction

The coronavirus disease 2019 (COVID-19) pandemic is disrupting health services worldwide. Women's health care is often acute and in continual demand, with poor health outcomes seen in women's health in particular in the recent Ebola and Swine flu epidemics. Regrettably, early reports globally and in the UK have shown a rise in the stillbirth rate. We aimed to evaluate the provision of obstetrics and gynaecology services in the UK during the acute phase of the COVID-19 pandemic.

Methods

We undertook an interview-based national survey of junior doctors in obstetrics and gynaecology in women’s healthcare units in the National Health Service using the network of the UK Audit and Research Collaborative in Obstetrics and Gynaecology. We sought responses on general training, labour ward care, antenatal and postnatal care, benign gynaecology and gynaecology oncology services.

Results

We received responses from 148/155 units (95%) contacted. Most completed specific training drills for managing obstetric and gynaecological emergencies (89/148, 60.1%) and two-person donning and doffing of personal protective Equipment (PPE) (96/148, 64.9%). The majority of surveyed units implemented COVID-19-specific protocols (130/148, 87.8%), offered adequate PPE (135/148, 91.2%) and operated dedicated COVID-19 emergency theatres (105/148,70.8%). Most units suspended elective gynaecology services (131/148, 88.5%). The 2-week referral pathway for oncological gynaecology was not affected in half of the units (76/148,51.4%), but half reported a planned reduction in oncology surgery (82/148, 55.4%)

Discussion

Women's health care services have responded well to the acute phase of the COVID-19 pandemic, however further planning is required for the long term.

Intralipid infusion at time of embryo transfer in women with history of recurrent implantation failure: A systematic review and meta-analysis

AIM

Recurrent implantation failure (RIF) affects 10% of couples undergoing assisted conception, often due to poor endometrial receptivity. We conducted a systematic review and meta-analysis to evaluate the effectiveness of Intra-venous intralipid (IVI) in improving pregnancy rates in women with history of RIF using.

METHODS

We searched MEDLINE, EMBASE, and CENTRAL for any randomized trials evaluating the use of IVI at the time of embryo transfer in women undergoing assisted conception until September 2020. We extracted data in duplicate and assessed risk of bias using the Cochrane Risk of Bias tools. We meta-analyzed data using a random effect model.

RESULTS

We included five randomized trials reporting on 843 women with an overall moderate risk of bias. All trials used 20% IVI solution at the time of embryo transfer compared to normal saline infusion or no intervention (routine care). The IVI group had a higher chance of clinical pregnancy (172 vs 119, risk ratio [RR] 1.55, 95% confidence interval [CI] 1.16-2.07, I² 44.2%) and live birth (132 vs 73, RR 1.83, 95% CI 1.42-2.35, I² 0%) post treatment compared to no intervention. Our findings are limited by the small sample size and the variations in treatment protocols and population characteristics.

CONCLUSION

There is limited evidence to support the use of IVI at the time of embryo transfer in women with the history of RIF. More research is needed before adopting it in clinical practice.

Quantifying CD138+ cells in the endometrium to assess chronic endometritis in women at risk of recurrent pregnancy loss: A prospective cohort study and rapid review

OBJECTIVE

To determine the value of uterine CD138+ cells, as a marker of chronic endometritis, in predicting subsequent reproductive outcome in women with history of recurrent pregnancy loss.

DESIGN

A prospective longitudinal study.

SETTING

Tertiary specialized clinic.

PATIENTS

Women with history of recurrent pregnancy loss or implantation failure over a 12-months follow-up period.

INTERVENTION

We quantified the CD138+ cells/high powered field (hpf) using immunohistochemistry and image analysis of endometrial biopsies obtained during the secretory stage post ovulation.

MAIN OUTCOME MEASURES

Live birth and subsequent pregnancy loss. We calculated the receiver operator curve for predicting subsequent pregnancy loss and reported using relative risk (RR) and 95% confidence intervals (CI).

RESULTS

We enrolled 344 women of whom 88 became pregnant (88/344, 25.5%). Half of them had a subsequent live birth (47/88, 53%) and the rest lost their pregnancy (41/88, 46%). The median CD138+ score was significantly lower in the live birth group (P < 0.005) and women with a CD138+ score ≥ 16/hpf had a higher risk of subsequent miscarriage (RR 10.0, 95% CI 2.78-36.02). CD138+ cells count showed a good prediction for subsequent pregnancy loss in high-risk women with an area under the curve of 0.75 (95% CI 0.59-0.82, P = 0.01). A cut-off value of 4-6 cells/hpf offered the best predictive accuracy with higher scores predicting worse reproductive outcome. Our findings are limited by the small event rate and the sample size of our cohort.

CONCLUSION

Quantifying CD138+ cells by immunohistochemistry in women with a history of recurrent pregnancy loss is helpful to diagnose chronic endometritis and predict subsequent reproductive outcome.

Are trainees working in obstetrics and gynecology confident and competent in the care of frail gynecological oncology patients?

INTRODUCTION

Older patients undergoing cancer surgery are at increased risk of post-operative complications, prolonged hospital stay, and mortality. Identification of frailty can help predict patients at high risk of peri-operative complications and allow a collaborative, multidisciplinary team approach to their care. A survey was conducted to assess the confidence and knowledge of trainees in obstetrics and gynecology regarding identification and management of peri-operative issues encountered in frail gynecological oncology patients.

METHODS

A web-based survey was distributed via the Audit and Research in Gynaecological Oncology (ARGO) collaborative and UK Audit and Research Collaborative in Obstetrics and Gynaecology (UKARCOG) . The survey on the management of frail peri-operative patients was disseminated to doctors-in-training (trainees) working in obstetrics and gynecology in the United Kingdom (UK) and Ireland. Specialty (ST1-7), subspecialty, and general practice trainees, non-training grade doctors, and foundation year doctors currently working in obstetrics and gynecology were eligible. Consultants were excluded. Study data were collected using REDCAP software hosted at the University of Manchester. Responses were collected over a 6-week period between January and February 2020.

RESULTS

Of the 666 trainees who participated, 67% (425/666) reported inadequate training in peri-operative management of frail patients. Validated frailty assessment tools were used by only 9% (59/638) of trainees and less than 1% (4/613) were able to correctly identify all the diagnostic features of frailty. Common misconceptions included the use of chronological age and gender in frailty assessments. The majority of trainees (76.5%, 448/586) correctly answered a series of questions relating to mental capacity; however, only 6% (36/606) were able to correctly identify all three diagnostic features of delirium. A total of 87% (495/571) of trainees supported closer collaboration with geriatricians and a multidisciplinary approach.

CONCLUSIONS

Obstetrics and gynecology trainees reported inadequate training in the peri-operative care of frail gynecological oncology patients, and overwhelmingly favored input from geriatricians. Routine use of validated frailty assessment tools may aid diagnosis of frailty in the peri-operative setting. There is an unmet need for formal education in the management of frail surgical patients within the UK and Irish obstetrics and gynecology curriculum.

Provision of obstetrics and gynaecology services during the COVID-19 pandemic: a survey of junior doctors in the UK National Health Service

Objective

The coronavirus disease 2019 (COVID‐19) pandemic is disrupting health services worldwide. We aimed to evaluate the provision of obstetrics and gynaecology services in the UK during the acute phase of the COVID‐19 pandemic.

Design

Interview‐based national survey.

Setting

Women's healthcare units in the National Health Service.

Population

Junior doctors in obstetrics and gynaecology.

Methods

Participants were interviewed by members of the UK Audit and Research in Obstetrics and Gynaecology trainees' collaborative between 28 March and 7 April 2020. We used a quantitative analysis for closed‐ended questions and a thematic framework analysis for open comments.

Results

We received responses from 148/155 units (95%), most of the participants were in years 3–7 of training (121/148, 82%). Most completed specific training drills for managing obstetric and gynaecological emergencies in women with COVID‐19 (89/148, 60.1%) and two‐person donning and doffing of Personal Protective Equipment (PPE) (96/148, 64.9%). The majority of surveyed units implemented COVID‐19‐specific protocols (130/148, 87.8%), offered adequate PPE (135/148, 91.2%) and operated dedicated COVID‐19 emergency theatres (105/148, 70.8%). Most units reduced face‐to‐face antenatal clinics (117/148, 79.1%) and suspended elective gynaecology services (131/148, 88.5%). The 2‐week referral pathway for oncological gynaecology was not affected in half of the units (76/148, 51.4%), but half reported a planned reduction in oncology surgery (82/148, 55.4%).

Conclusion

The provision of obstetrics and gynaecology services in the UK during the acute phase of the COVID‐19 pandemic seems to be in line with current guidelines, but strategic planning is needed to restore routine gynaecology services and ensure safe access to maternity care in the long term.

Tweetable abstract

Provision of obstetrics and gynaecology services during the acute phase of COVID‐19 is in line with current guidelines, strategic planning is needed to restore routine services and ensure safe access to care in the long term.

Provision of obstetrics and gynaecology services during the acute phase of COVID‐19 is in line with current guidelines, strategic planning is needed to restore routine services and ensure safe access to care in the long term.

This paper includes Author Insights, a video abstract available at https://vimeo.com/rcog/authorinsights16313

Early versus delayed urinary catheter removal after hysterectomy: A systematic review and meta-analysis

OBJECTIVES

In bladder drainage, an essential part of post-hysterectomy care, the optimal timing for removing the urinary catheter is unclear. Our objective was to evaluate the risks and benefits of early (<6 h) vs delayed (>6 h) catheter removal post-hysterectomy.

STUDY DESIGN

A systematic review searching MEDLINE, EMBASE and Cochrane CENTRAL from inception till May 2019 for randomised trials of women undergoing hysterectomy. We reported on urinary retention, positive urine culture, urinary tract infection (UTI) (defined by symptoms and/or antibiotic use), post-operative pyrexia, time to ambulation, and length of hospital stay. We assessed risk of bias in included trials and used a random-effect model to generate risk ratios (RR) for dichotomous outcomes and weighted mean differences (WMD) for continuous outcomes, with 95 % confidence intervals (CI).

RESULTS

Of 1020 potentially relevant citations, we included 10 randomised trials (1120 women). Four trials had low risk of bias for randomisation and allocation concealment while five had low risk for outcome assessment and selective reporting. Compared to delayed removal, women in the early catheter removal group had a higher risk of urinary retention and needing re-catheterisation (10 RCTs, RR 3.61, 95 %CI 1.21-9.21, I² = 56 %). There was some reduction in the risk of post-operative UTI (6 RCTs, RR 0.42, 95 %CI 0.18 to 0.96, I² = 0 %), but we did not find a significant difference in post-operative pyrexia (6 RCTs, RR 0.73, 95 %CI 0.43-1.24, I² = 18 %) or positive urine cultures (6 RCTs, RR of 0.56, 95 %CI 0.27-1.12, I² = 55 %). There was no significant difference in the average time to ambulation (3RCTs, WMD -4.6, 95 %CI -9.16 to -0.18, I² = 98 %) and length of hospital stay (3RCTs, WMD -1.05, 95 %CI -2.42 to 0.31, I² = 98 %). Our meta-regression on the provision of prophylactic antibiotics did not show a significant effect on the reported outcomes. Our analysis was limited by our inability to adjust for potential effect modifiers such as the surgical route.

CONCLUSIONS

Early removal of the urinary catheter <6 h post-hysterectomy seems to increase the risk of urinary retention and needing re-catheterisation, but may reduce post-operative UTI.

The oncogene Gankyrin is expressed in testicular cancer and contributes to cisplatin sensitivity in embryonal carcinoma cells

Background

Testicular germ cell cancer (TGCC) develops from pre-malignant germ neoplasia in situ (GCNIS) cells. GCNIS originates from fetal gonocytes (POU5F1⁺/MAGE-A4⁻), which fail to differentiate to pre-spermatogonia (POU5F1⁻/MAGE-A4⁺) and undergo malignant transformation. Gankyrin is an oncogene which has been shown to prevent POU5F1 degradation and specifically interact with MAGE-A4 in hepatocellular carcinoma (HCC) cells. We aimed to investigate the role of Gankyrin in progression from gonocyte to pre-invasive GCNIS and subsequent invasive TGCC.

Methods

We determined Gankyrin expression in human fetal testicular tissue (gestational weeks 9–20; n = 38), human adult testicular tissue with active spermatogenesis (n = 9), human testicular tissue with germ cell maturation delay (n = 4), testicular tissue from patients with pre-invasive GCNIS (n = 6), and invasive TGCC including seminoma (n = 6) and teratoma (n = 7). Functional analysis was performed in-vitro by siRNA knock-down of Gankyrin in the NTera2 cells (derived from embryonal carcinoma).

Results

Germ cell expression of Gankyrin was restricted to a sub-population of prespermatogonia in human fetal testes. Nuclear Gankyrin was also expressed in GCNIS cells of childhood and adult pre-invasive TGCC patients, and in GCNIS from seminoma and non-seminoma patients. Cytoplasmic expression was observed in seminoma tumour cells and NTera2 cells. Gankyrin knock-down in NTera2 cells resulted in an increase in apoptosis mediated via the TP53 pathway, whilst POU5F1 expression was unaffected. Furthermore, Gankyrin knock-down in NTera2 cells increased cisplatin sensitivity with an increase in cell death (13%, p < 0.05) following Gankyrin knock-down, when compared to cisplatin treatment alone, likely via BAX and FAS. Our results demonstrate that Gankyrin expression changes in germ cells during normal transition from gonocyte to prespermatogonia. In addition, changes in Gankyrin localisation are associated with progression of pre-invasive GCNIS to invasive TGCC. Furthermore, we found that Gankyrin is involved in the regulation of NTera2 cell survival and that a reduction in Gankyrin expression can modulate cisplatin sensitivity.

Conclusions

These results suggest that manipulation of Gankyrin expression may reduce the cisplatin dose required for the treatment of TGCC, with benefits in reducing dose-dependent side effects of chemotherapy. Further studies are required in order to assess the effects of modulating Gankyrin on GCNIS/TGCC using in vivo models.

Evaluation of large aberrations using a lateral-shear interferometer having variable shear

A variable shear lateral shearing interferometer consisting of two holographically produced crossed diffraction gratings is used to test nonrotationally symmetric wavefronts having aberrations greater than 100 wavelengths and slope variations of more than 400 wavelengths/diameter. Comparisons are made with results of Twyman-Green interferometric tests for wavefront aberrations of up to thirty wavelengths. The results indicate that small wavefront aberrations can be measured as accurately with the lateral-shear interferometer as with the Twyman-Green interferometer and that aberrations that cannot be measured at all with a Twyman-Green interferometer can be measured to about 1% accuracy or better.

Method for evaluating lateral shearing interferograms

Wavefront shearing interferometers have inherent advantages over more conventional interferometers because they do not need a separate reference wavefront. However, the fringe patterns are less directly related to the wavefront shape. In this paper, a method is described that uses data obtained from two lateral shear interferograms sheared in orthogonal directions to describe a wavefront of any arbitrary shape. Analysis of the data defines the wavefront on a regular grid, using a least squares criterion to match the measured data to the reconstructed shear data. Because each point on the final wavefront is involved in at most four measurements, the matrices tend to have many zero elements, making them easily solvable by simple numerical techniques, even for several hundred points. An error analysis indicates that the accuracy of the final results can be as good as the accuracy of the measured data. The procedure is described, and results of a typical analysis are shown.

Computer program for the analysis of interferometric test data

The over-all design and capabilities of several proprietary computer programs to reduce and analyze various types of interferometric data are described. The following problems and methods of solution are discussed in greater detail: scaling and mapping errors; generation of artificial interferograms and holograms for testing without null lenses; combination of overlapping partial-aperture interferograms; the Ritchey-Common test for flat mirrors; and fitting of interferometric data with orthogonal polynomials.

General analysis of aplanatic cassegrain, gregorian, and schwarzschild telescopes

The properties of two-conic reflecting aplanats are analyzed and discussed on the basis of third order aberration theory. Techniques for designing infinite conjugate two mirror aplanats and computing their image properties are developed. The secondary mirror alignment characteristics of Ritchey-Chrétien and aplanatic Gregorian telescopes are examined and neutral point locations defined. Design configurations corrected for a third Seidel aberration (astigmatism, image curvature, or distortion) are identified and their properties discussed. The properties of Ritchey-Chrétien and aplanatic Gregorian telescopes are compared.

A variable refractive null lens

Null lenses, for use with rotationally symmetric but nonspherical surfaces, are extremely useful for testing during production. In general, each different system to be tested requires a different null lens. A variable null lens is proposed which consists of two aspheric plates, each of which introduces approximately fourth- or sixth-order spherical aberration. When the plates are inserted in a diverging beam, the effect on the wavefront may be changed by varying the plate spacing. The system may be used to test parabolas and other nonspherical mirrors at center of curvature, aspheric plates in conjunction with spherical mirrors, and various other systems. Once the two plates have been produced and measured, the spacing of the plates used may be determined for each test. This would normally be done by computer, using any of the optimization techniques for lens design. Examples are shown, and an estimate of obtainable accuracy is given.