2020 Hong Kong College of Obstetricians and Gynaecologists guideline on investigations of premenopausal women with abnormal uterine bleeding

Abnormal uterine bleeding in premenopausal women is a common gynaecological symptom and composes of abnormality in the frequency, duration, regularity, and flow volume of menstruation. It could constitute the presentation of various gynaecological malignancies. An appropriate history and physical examination are mandatory to ascertain the diagnosis. Depending on the clinical condition, a complete blood picture, thyroid function test, clotting profile, chlamydia test, cervical smear, and pregnancy test can be performed. Ultrasound should be performed in cases with a pelvic mass, unsatisfactory physical examination, persistent symptoms, or no response to medical treatment. In women aged ≥40 years, an out-patient endometrial biopsy with Pipelle should be performed. In women aged <40 years with risk factors for endometrial cancer, persistent symptoms, or no response to medical treatment, an endometrial biopsy should be performed to rule out endometrial cancer. Hysteroscopy or saline infusion sonohysterography is more sensitive than ultrasound for diagnosing endometrial pathology. Details of the above recommendations are presented.

CDK2 regulates the NRF1/Ehmt1 axis during meiotic prophase I

Palmer et al. identify NRF1 as a novel CDK2 interactor and substrate. This interaction was found to be important for the DNA-binding activity of NRF1. Their findings demonstrate that the loss of CDK2 expression impairs the regulation of NRF1 transcriptional activity, leading to inappropriate transcription during meiotic division.

Meiosis generates four genetically distinct haploid gametes over the course of two reductional cell divisions. Meiotic divisions are characterized by the coordinated deposition and removal of various epigenetic marks. Here we propose that nuclear respiratory factor 1 (NRF1) regulates transcription of euchromatic histone methyltransferase 1 (EHMT1) to ensure normal patterns of H3K9 methylation during meiotic prophase I. We demonstrate that cyclin-dependent kinase (CDK2) can bind to the promoters of a number of genes in male germ cells including that of Ehmt1 through interaction with the NRF1 transcription factor. Our data indicate that CDK2-mediated phosphorylation of NRF1 can occur at two distinct serine residues and negatively regulates NRF1 DNA binding activity in vitro. Furthermore, induced deletion of Cdk2 in spermatocytes results in increased expression of many NRF1 target genes including Ehmt1. We hypothesize that the regulation of NRF1 transcriptional activity by CDK2 may allow the modulation of Ehmt1 expression, therefore controlling the dynamic methylation of H3K9 during meiotic prophase.

Levator ani muscle avulsion is a risk factor for expulsion within 1 year of vaginal pessary placed for pelvic organ prolapse

OBJECTIVE

The aim of this study was to investigate whether the presence of levator ani muscle (LAM) avulsion is associated with expulsion within 1 year of a vaginal pessary placed for pelvic organ prolapse (POP).

METHODS

This was a prospective observational study of consecutive women with symptomatic POP, who had not received treatment for the condition before the consultation and opted for vaginal pessary placement in our center. Volume acquisition was performed before pessary insertion and offline analysis of the 3D/4D transperineal ultrasound volume data was performed. LAM was assessed on maximum pelvic floor muscle contraction (PFMC) and hiatal dimensions were assessed at rest, on PFMC and on maximum Valsalva. Results were compared between women in whom the pessary was retained for 1 year and those in whom the pessary was expelled within 1 year.

RESULTS

The datasets of 255 women were analyzed including 147 (57.6%) women who had a vaginal pessary continuously in place over 1 year and 108 (42.4%) with pessary expulsion. Mean age was 63.2 (SD, 9.9) years and median parity was 3 (2-4). Eighteen (7.1%) had Stage I, 164 (64.3%) Stage II, 67 (26.3%) Stage III and six (2.4%) Stage IV POP. Women with vaginal pessary expulsion within 1 year had significantly larger hiatal dimensions at rest and on Valsalva, larger hiatal area during rest, PFMC and Valsalva and higher rate of LAM avulsion (53.7% vs 27.2%, P < 0.01) compared with women in whom the pessary was retained for 1 year. After controlling for potential confounders, LAM avulsion remained a risk factor (OR, 3.18, P < 0.01) of vaginal pessary expulsion within 1 year.

CONCLUSIONS

Women in whom a vaginal pessary was expelled within 1 year of placement for POP had a larger hiatus. Presence of LAM avulsion was associated with a three-fold increase in the risk of expulsion of a vaginal pessary within 1 year. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Urinary symptoms and impaired quality of life in female ketamine users: persistence after cessation of use

OBJECTIVE

To compare the urinary symptoms and quality of life in ex-ketamine abusers and controls.

DESIGN

Prospective observational study.

SETTING

A hospital in Hong Kong.

PATIENTS

Female ex-ketamine abusers admitted to a local drug rehabilitation centre and age-matched controls attending a general gynaecology clinic between December 2009 and April 2010.

MAIN OUTCOME MEASURES

Evaluation of urinary symptoms based on a 3-day bladder diary, and responses to the Urogenital Distress Inventory Short Form (UDI-6) and the Incontinence Impact Questionnaire Short Form (IIQ-7). The study group had repeat measurements 3 months later.

RESULTS

Overall, 90% of ex-ketamine abusers had active urinary symptoms. On average, they had increased 24-hour urinary frequency (10.0 vs 5.8; P=0.001) and lower maximum voided volume (253.3 mL vs 401.9 mL; P<0.001) compared to controls. Correspondingly, the median functional bladder capacity was smaller (195.3 mL vs 261.2 mL; P=0.011) and the mean UDI-6 and IIQ-7 scores were higher (P<0.001). Among those who abused ketamine for 2 years or more, the mean UDI-6 and IIQ-7 scores were higher (P=0.03, P=0.02 respectively). When they stopped abusing ketamine for 3 months or more, their mean 24-hour urinary frequency had decreased (P=0.03), the maximum voided volume had increased (P=0.03) and the mean UDI-6 and IIQ-7 scores had decreased (P=0.04, P=0.02 respectively), although they were still higher than in controls. After 3 more months, in the ex-ketamine abusers there had been a further decrease in 24-hour urinary frequency (P=0.01) and a further improvement in quality of life based on mean UDI-6 scores (P=0.04) but nevertheless poorer than the control group (P<0.01).

CONCLUSION

Female ex-ketamine abusers had significant urinary symptoms affecting their quality of life when studied at a mean of 8 (range, 0.5-48) months after cessation of use. The symptom severity was inversely correlated with the duration of cessation; though they improved with time, some still persisted.

Numerical simulation of turbulent gas flames in tubes

Computational fluid dynamics (CFD) is an emerging technique to predict possible consequences of gas explosion and it is often considered a powerful and accurate tool to obtain detailed results. However, systematic analyses of the reliability of this approach to real-scale industrial configurations are still needed. Furthermore, few experimental data are available for comparison and validation. In this work, a set of well documented experimental data related to the flame acceleration obtained within obstacle-filled tubes filled with flammable gas-air mixtures, has been simulated. In these experiments, terminal steady flame speeds corresponding to different propagation regimes were observed, thus, allowing a clear and prompt characterisation of the numerical results with respect to numerical parameters, as grid definition, geometrical parameters, as blockage ratio and to mixture parameters, as mixture reactivity. The CFD code AutoReagas was used for the simulations. Numerical predictions were compared with available experimental data and some insights into the code accuracy were determined. Computational results are satisfactory for the relatively slower turbulent deflagration regimes and became fair when choking regime is observed, whereas transition to quasi-detonation or Chapman-Jogouet (CJ) were never predicted.