Obstetrics and Gynaecology - Research Publications
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ItemMesenchymal Stem/Stromal Cells and Their Role in Oxidative Stress Associated with Preeclampsia(YALE J BIOLOGY MEDICINE, INC, 2022-03-01)Preeclampsia (PE) is a serious medically important disorder of human pregnancy, which features de novo pregnancy-induced hypertension and proteinuria. The severe form of PE can progress to eclampsia, a convulsive, life-threatening condition. When placental growth and perfusion are abnormal, the placenta experiences oxidative stress and subsequently secretes abnormal amounts of certain pro-angiogenic factors (eg, PlGF) as well as anti-angiogenic factors (eg, sFlt-1) that enter the maternal circulation. The net effect is damage to the maternal vascular endothelium, which subsequently manifests as the clinical features of PE. Other than delivery of the fetus and placenta, curative treatments for PE have not yet been forthcoming, which reflects the complexity of the clinical syndrome. A major source of reactive oxygen species that contributes to the widespread maternal vascular endothelium damage is the PE-affected decidua. The role of decidua-derived mesenchymal stem/stromal cells (MSC) in normotensive and pathological placenta development is poorly understood. The ability to respond to an environment of oxidative damage is a "universal property" of MSC but the biological mechanisms that MSC employ in response to oxidative stress are compromised in PE. In this review, we discuss how MSC respond to oxidative stress in normotensive and pathological conditions. We also consider the possibility of manipulating the oxidative stress response of abnormal MSC as a therapeutic strategy to treat preeclampsia.
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ItemPoint-of-care HPV DNA testing of self-collected specimens and same-day thermal ablation for the early detection and treatment of cervical pre-cancer in women in Papua New Guinea: a prospective, single-arm intervention trial (HPV-STAT).(Elsevier BV, 2022-09)BACKGROUND: WHO recommends human papillomavirus (HPV) testing and same-day treatment for cervical screening in low-income and middle-income countries (LMICs); however, few published data exist on the validity of the strategy. We aimed to evaluate the clinical performance, treatment completion rates, adverse events profile, and acceptability of a fully integrated strategy, comprising point-of-care HPV DNA testing of self-collected specimens and same-day thermal ablation, for screening of cervical cancer in women in Papua New Guinea. METHODS: HPV-STAT was a large-scale, prospective, single-arm intervention trial conducted at two clinical sites in Papua New Guinea. Cervical screening clinics with an on-site consultant gynaecologist were selected in consultation with national and provincial health authorities, church health services, and local stakeholders. Eligible participants were women aged 30-59 years attending cervical screening services at the two clinics, who were willing to comply with study procedures and able to provide written informed consent. Women self-collected vaginal specimens for point-of-care GeneXpert testing (Cepheid, Sunnyvale, CA, USA) for oncogenic HPV types. Women testing positive for HPV underwent pelvic examination followed by same-day thermal ablation or referral for gynaecology review. All HPV-positive women and a 15% random sample of HPV-negative women provided a clinician-collected cervical specimen for liquid-based cytology. The primary outcome was clinical performance (ie, sensitivity, specificity, positive predictive value [PPV], and negative predictive value [NPV]) of the strategy for the detection of high-grade squamous intraepithelial lesion (HSIL) or worse. This trial is registered with ISRCTN, ISRCTN13476702. FINDINGS: Between June 5, 2018, and Jan 6, 2020, we recruited 4285 women, 3638 (84·9%) of whom tested negative for HPV and 647 (15·1%) tested positive for one or more oncogenic HPV type. Sensitivity of the algorithm to detect HSIL or worse was 85·4% (95% CI 81·0-89·6), with specificity 89·6% (88·6-90·6), PPV 35·2% (31·6-39·0), and NPV 98·9% (98·6-99·2). Among HPV-positive women, 602 (93·0%) received same-day thermal ablation and 42 (6·5%) were referred for gynaecology review, 37 (88·1%) of whom attended. Acceptability was high among both HPV-positive and HPV-negative women. Among the 329 HPV-positive women who attended a 3-month follow-up visit, 51 (15·5%) reported mild adverse symptoms that resolved in all cases by the follow-up visit. There were no serious adverse events. INTERPRETATION: We conducted the first real-world evaluation of a fully integrated point-of-care HPV self-collect, test, and treat strategy for same-day cervical screening in a LMIC and found it to be effective, acceptable, and safe when implemented at scale in primary health-care facilities in Papua New Guinea. Our findings support the introduction and scale-up of HPV screening and treatment for the control and elimination of cervical cancer in LMICs, as recommended by WHO. FUNDING: Australian National Health and Medical Research Council.
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ItemImmunogenicity and safety of quadrivalent and 9-valent human papillomavirus vaccines in Indian clinical trial participants.(Informa UK Limited, 2022-11-30)The quadrivalent human papillomavirus (qHPV; HPV6/11/16/18) and 9-valent HPV (9vHPV; HPV6/11/16/18/31/33/45/52/58) vaccines have demonstrated efficacy, immunogenicity, and safety in international clinical trials. We report outcomes from three completed clinical trials in India: a single-arm study (V501-029 [NCT00380367]) in Indian girls (aged 9-15 years; N = 110) evaluating qHPV vaccine immunogenicity and safety; a subgroup analysis (n = 225) of Indian girls/boys (9-15 years) and women (16-26 years) from a global study (V503-002 [NCT00943722]) evaluating 9vHPV vaccine immunogenicity and safety; and a qHPV vaccine post-marketing safety surveillance study (V501-125) in Indian females (aged 9-45 years; N = 188) vaccinated during routine care. In V501-029 and V503-002, HPV vaccines were administered as 3 doses (Day 1, Month 2, Month 6). Serum HPV antibodies were evaluated by competitive Luminex immunoassays at Day 1 and Month 7 (both studies) and Months 12, 24, and 36 (V503-002 only). Adverse events (AEs) were collected by Vaccination Report Card. In V501-125, participants were actively surveilled for serious AEs (SAEs) within 30 days post-qHPV vaccination. In per-protocol analyses, qHPV and 9vHPV vaccines induced robust anti-HPV6/11/16/18 (V501-029) and HPV6/11/16/18/31/33/45/52/58 (V503-002) responses, respectively; ≥97% of participants seroconverted at Month 7 for each vaccine HPV type in both studies, and antibody responses persisted through 36 months in V503-002. The most common AEs were injection-site-associated. Most AEs were mild/moderate; no deaths, vaccine-related SAEs, or discontinuations due to AEs were reported. In V501-125, no SAE was reported. Overall, the qHPV and 9vHPV vaccines elicited robust antibody responses and were generally well tolerated in Indian participants.
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ItemA longitudinal examination of perinatal testosterone, estradiol and vitamin D as predicators of handedness outcomes in childhood and adolescence(ROUTLEDGE JOURNALS, TAYLOR & FRANCIS LTD, 2022-08-10)The developmental origins of handedness remain elusive, though very early emergence suggests individual differences manifesting in utero could play an important role. Prenatal testosterone and Vitamin D exposure are considered, yet findings and interpretations remain equivocal. We examined n = 767 offspring from a population-based pregnancy cohort (The Raine Study) for whom early biological data and childhood/adolescent handedness data were available. We tested whether 18-week maternal circulatory Vitamin D (25[OH]D), and testosterone and estradiol from umbilical cord blood sampled at birth predicted variance in direction of hand preference (right/left), along with right- and left-hand speed, and the strength and direction of relative hand skill as measured by a finger-tapping task completed at 10 (Y10) and/or 16 (Y16) years. Although higher concentrations of Vitamin D predicted more leftward and less lateralized (regardless of direction) relative hand skill profiles, taken as a whole, statistically significant findings typically did not replicate across time-point (Y10/Y16) or sex (male/female) and were rarely detected across different (bivariate/multivariate) levels of analysis. Considering the number of statistical tests and generally inconsistent findings, our results suggest that perinatal testosterone and estradiol contribute minimally, if at all, to subsequent variance in handedness. Vitamin D, however, may be of interest in future studies.
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ItemPlacental OLAH Levels Are Altered in Fetal Growth Restriction, Preeclampsia and Models of Placental Dysfunction(MDPI, 2022-09-01)Previously, we identified elevated transcripts for the gene Oleoyl-ACP Hydrolase (OLAH) in the maternal circulation of pregnancies complicated by preterm fetal growth restriction. As placental dysfunction is central to the pathogenesis of both fetal growth restriction and preeclampsia, we aimed to investigate OLAH levels and function in the human placenta. We assessed OLAH mRNA expression (qPCR) throughout pregnancy, finding placental expression increased as gestation progressed. OLAH mRNA and protein levels (Western blot) were elevated in placental tissue from cases of preterm preeclampsia, while OLAH protein levels in placenta from growth-restricted pregnancies were comparatively reduced in the preeclamptic cohort. OLAH expression was also elevated in placental explant tissue, but not isolated primary cytotrophoblast cultured under hypoxic conditions (as models of placental dysfunction). Further, we discovered that silencing cytotrophoblast OLAH reduced the expression of pro- and anti-apoptosis genes, BAX and BCL2, placental growth gene, IGF2, and oxidative stress gene, NOX4. Collectively, these findings suggest OLAH could play a role in placental dysfunction and may be a therapeutic target for mitigating diseases associated with this vital organ. Further research is required to establish the role of OLAH in the placenta, and whether these changes may be a maternal adaptation or consequence of disease.
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ItemCerebral Arterial Asymmetries in the Neonate: Insight into the Pathogenesis of Stroke(MDPI, 2022-03-01)Neonatal and adult strokes are more common in the left than in the right cerebral hemisphere in the middle cerebral arterial territory, and adult extracranial and intracranial vessels are systematically left-dominant. The aim of the research reported here was to determine whether the asymmetric vascular ground plan found in adults was present in healthy term neonates (n = 97). A new transcranial Doppler ultrasonography dual-view scanning protocol, with concurrent B-flow and pulsed wave imaging, acquired multivariate data on the neonatal middle cerebral arterial structure and function. This study documents for the first-time systematic asymmetries in the middle cerebral artery origin and distal trunk of healthy term neonates and identifies commensurately asymmetric hemodynamic vulnerabilities. A systematic leftward arterial dominance was found in the arterial caliber and cortically directed blood flow. The endothelial wall shear stress was also asymmetric across the midline and varied according to vessels’ geometry. We conclude that the arterial structure and blood supply in the brain are laterally asymmetric in newborns. Unfavorable shearing forces, which are a by-product of the arterial asymmetries described here, might contribute to a greater risk of cerebrovascular pathology in the left hemisphere.
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ItemThe Impact of Gestational Diabetes Mellitus on Human Milk Metabolic Hormones: A Systematic Review.(MDPI AG, 2022-09-01)Gestational diabetes mellitus (GDM) is a common pregnancy complication with short- and long-term health consequences for the infant and mother. Breastfeeding is the recommended mode of feeding as it offers an opportunity to reduce the risk of GDM consequences, likely partially mediated through changes in human milk (HM) composition. This review systematically reviewed 12 identified studies that investigated the impact of GDM on concentrations of HM metabolic hormones. Meta-analysis was not possible due to significant heterogeneity in study designs and hormone measurement techniques. The risk of bias was assessed using the National Institute for Clinical Excellence (NICE) tool. The methodological qualities were medium in half of the studies, while 25% (3/12) of studies carried a high risk of bias. Significant relationships were reported between GDM and concentrations of HM ghrelin (3/3 studies), insulin (2/4), and adiponectin (2/6), which may play an integral role in infant growth and development. In conclusion, preliminary evidence suggests that GDM may alter HM metabolic hormone concentrations; however, these relationships may be limited to the early lactation stage.
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ItemSerum Collected from Preeclamptic Pregnancies Drives Vasoconstriction of Human Omental Arteries-A Novel Ex Vivo Model of Preeclampsia for Therapeutic Development(MDPI, 2022-09-01)New-onset maternal hypertension is a hallmark of preeclampsia, driven by widespread endothelial dysfunction and systemic vasoconstriction. Here, we set out to create a new ex vivo model using preeclamptic serum to cause injury to the endothelium, mimicking vascular dysfunction in preeclampsia and offering the potential to evaluate candidate therapeutic interventions. Human omental arteries were collected at caesarean section from normotensive pregnant patients at term (n = 9). Serum was collected from pregnancies complicated by preterm preeclampsia (birth < 34 weeks’ gestation, n = 16), term preeclampsia (birth > 37 weeks’ gestation, n = 5), and healthy gestation-matched controls (preterm n = 16, term n = 12). Using wire myography, we performed ex vivo whole vessel assessment where human omental arteries were treated with increasing doses of each serum treatment (2−20%) and vasoreactivity was assessed. All pregnant serum treatments successfully drove vasoconstriction; no significant difference was observed in the degree of vasoconstriction when exposed to preeclamptic or control serum. We further demonstrated the ability of esomeprazole (a candidate therapeutic for preeclampsia; 0.1−100 µM) to drive vasorelaxation of pre-constricted vessels (only with serum from preeclamptic patients). In summary, we describe a novel human physiological model of preeclamptic vascular constriction. We demonstrate its exciting potential to screen drugs for their therapeutic potential as treatment for vasoconstriction induced by preeclampsia.
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ItemAssessment of the Proton Pump Inhibitor, Esomeprazole Magnesium Hydrate and Trihydrate, on Pathophysiological Markers of Preeclampsia in Preclinical Human Models of Disease(MDPI, 2022-09-01)Previously, we demonstrated that the proton pump inhibitor, esomeprazole magnesium hydrate (MH), could have potential as a repurposed treatment against preeclampsia, a serious obstetric condition. In this study we investigate the difference in the preclinical effectiveness between 100 µM of esomeprazole MH and its hydration isomer, esomeprazole magnesium trihydrate (MTH). Here, we found that both treatments reduced secretion of sFLT-1 (anti-angiogenic factor) from primary cytotrophoblast, but only esomeprazole MH reduced sFLT-1 secretion from primary human umbilical vein endothelial cells (assessed via ELISA). Both drugs could mitigate expression of the endothelial dysfunction markers, vascular cell adhesion molecule-1 and endothelin-1 (via qPCR). Neither esomeprazole MH nor MTH quenched cytotrophoblast reactive oxygen species production in response to sodium azide (ROS assay). Finally, using wire myography, we demonstrated that both compounds were able to induce vasodilation of human omental arteries at 100 µM. Esomeprazole is safe to use in pregnancy and a candidate treatment for preeclampsia. Using primary human tissues and cells, we validated that esomeprazole is effective in enhancing vascular relaxation, and can reduce key factors associated with preeclampsia, including sFLT-1 and endothelial dysfunction. However, esomeprazole MH was more efficacious than esomeprazole MTH in our in vitro studies.
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ItemInfertility and the Endometrium(IMR Press, 2022-09-01)