Delivery outcomes as a result of snoring as determined by standard sleep surveys.

Background: Sleep-disordered breathing (SDB), is an umbrella term that encompasses obstructive sleep apnea (OSA), central sleep apnea (CSA) and hypoventilation. is common but studies in the pregnant population are limited. Data suggests relationships between OSA and preeclampsia, but the relationship between snoring and pregnancy outcomes is unknown. Methods: A prospective study of 2224 singleton pregnancies was undertaken. Women were questioned using the Berlin Questionnaire (BQ- 2 or more categories where the score is positive.) and the Epworth Sleepiness Scale (ESS >10/24), the results compared with pregnancy outcomes with regard to hypertension in pregnancy. Results: Women having symptoms raising the possibility of OSA defined by the BQ with a score >7 was 45.5%, and using ESS with a score >10, was 36%. The birth and neonatal outcomes for self-reported snoring and increased daytime sleepiness showed increased adverse outcomes notably increased caesarean section rates and low APGAR scores but not birth before 37 weeks of gestation. Conclusion: Using questionnaires designed for the general population, the prevalence of possible undiagnosed OSA is high in the pregnant population. The increased adverse delivery and neonatal outcomes for self-reported snoring and increased daytime sleepiness with these tools indicated the need for further investigation of the links between snoring SDB and pregnancy outcomes.

The unfolded protein response and apoptotic regulation in the human placenta due to maternal cigarette smoking and pre-eclampsia.

Maternal cigarette smoking (CS) and pre-eclampsia (PE) alter placental function and expression of important proteins which maintain homeostasis. Two interlinked pathways of interest are the unfolded protein response (UPR) and apoptosis. The UPR is upregulated in the PE placenta, but no data is available on the effects of CS and how it correlates with apoptotic expression. Samples of human placental tissue from normotensive non-smokers (n = 8), women with PE (n = 8), and CS (n = 8) were analysed using immunohistochemistry for 3 UPR markers (phosphorylated PKR-like endoplasmic reticulum (ER) kinase (pPERK), inositol-requiring enzyme 1 (IRE1), activating transcription factor 6 (ATF6)), and an antibody microarray for 19 apoptotic and stress regulating markers. For the PE group compared to the normotensive group, staining for pPERK was increased in decidual tissue and villi, and for IRE1, the overall percentage of stained villi per field of view was increased. There were no differences in UPR expression comparing CS to controls. Of the apoptotic markers, only IκBα (Ser32/36), which is part of an inhibitory pathway, showed a significant decrease in the PE and CS groups compared to controls. These findings suggest UPR regulation is more evident in PE with a general increase in ER stress due to decreased inhibition of apoptosis as compared to CS for which UPR was not altered.

Fatty acid concentration of plasma, muscle, adipose and liver from beef heifers fed an encapsulated n-3 polyunsaturated fatty acid supplement.

Increasing the content of polyunsaturated fat in the human diet is a priority for reducing cardiovascular disease and cancer risks. Beef has the potential to contribute to the polyunsaturated fat content in the human diet; however, ruminants cannot synthesise many long-chain fatty acids de novo; they require dietary supplementation. The objectives of the current study were to evaluate (i) the effect of a partially rumen protected n-3 long-chain polyunsaturated fatty acid (LC-PUFA) dietary supplement on the fatty acid composition of muscle (Longissimus dorsi), adipose and liver tissues of beef heifers and (ii) the usefulness of blood plasma as a predictor of tissue concentrations of specific fatty acids. Charolais crossbred heifers (n = 20) were assigned to one of two isolipid dietary treatments namely palmitic acid (control) or an n-3 LC-PUFA supplement for a 91-day period. Blood plasma and adipose tissue samples were taken to determine the temporal effect of these diets on fatty acid composition (days 0, 10, 35 and 91), while liver and muscle samples were taken following slaughter. Dietary lipid source did not influence animal growth rate or body condition score. At day 91, the percentage differences between control and n-3 LC-PUFA heifers in concentrations of eicosapentaenoic acid were +61, +176 and +133 % in liver, muscle and adipose, respectively. For docosahexaenoic acid, at the same time point, the percentage differences were +57, +73 and +138 % for liver, muscle and adipose, respectively. Medium-to-strong positive correlation coefficients were evident for liver and plasma fatty acids, in particular, there were positive relationships with concentrations of total saturated fatty acid (SFA), total n-6 PUFA and total n-3 PUFA. This trend also extended to both the ratio of PUFA to SFA (slope (ß1) = 0.56 ±â€¯0.167, intercept (ß0) = 0.56, R2 = 0.61, P < 0.05) and the ratio of n-6 to n-3 PUFA (ß1 = 0.15 ±â€¯0.054, ß0 = 0.24, R2 = 0.52, P < 0.05). A strong correlation was also detected in the ratio of n-6 to n-3 in plasma and muscle tissue of heifers fed the n-3 LC-PUFA diet (ß1 = 0.53 ±â€¯0.089, ß0 = -0.31, R2 = 0.83, P < 0.001). The results of this study show that the n-3 LC-PUFA can be readily increased through targeted supplementation and that plasma concentrations of n-3 LC-PUFA are useful predictors of their concentrations in a number of economically important tissues.

Effect of Placental Growth Factor on Trophoblast-Endothelial Cell Interactions In Vitro.

Placental growth factor (PlGF) is an important angiogenic factor which has an emerging role in the clinical management of suspected preeclampsia. The role of PlGF in normal placental development is not completely understood and it is uncertain whether PlGF influences trophoblast and endothelial cell interactions central to uterine spiral artery remodelling, especially in variable oxygen conditions. A two-cell model of endovascular invasion was used. Tissue culture plates were coated with Matrigel™, on which fluorescent-labelled uterine microvascular endothelial cells (1 × 105/well) and HTR8/SVNeo cells were co-cultured (1 × 105/well) for 20 h. Co-cultures were treated with recombinant human PlGF (rhPlGF) (10 or 100 ng/mL) and incubated at either 21% O2 or 2% O2. Images were captured by fluorescence microscopy and analysed using ImageJ (n = 7). Data was analysed using SPSSv24. Treatment with rhPlGF did not improve integration in co-cultures irrespective of oxygen conditions but increased proliferation in 2% O2 of both trophoblast and endothelial cells. Expression of angiogenic factors VEGF, sFLT-1, PlGF and CXCL12 in both co-cultures and in isolated trophoblast cells was not altered by rhPlGF treatment. Expression of TLR-3 mRNA in co-cultures was increased by rhPlGF 100 ng/mL at 21% O2 (p = 0.03). PlGF contributes to trophoblast and endothelial cell proliferation in the setting of physiological hypoxia but does not influence trophoblast and endothelial cell interactions in an in vitro model of spiral artery remodelling. Upregulation of TLR-3 expression in co-cultures may indicate a role for PlGF in the placental inflammatory response.

Guidelines on suicide amongst anaesthetists 2019.

Anaesthetists are thought to be at increased risk of suicide amongst the medical profession. The aims of the following guidelines are: increase awareness of suicide and associated vulnerabilities, risk factors and precipitants; to emphasise safe ways to respond to individuals in distress, both for them and for colleagues working alongside them; and to support individuals, departments and organisations in coping with a suicide.

Advances in Infant Formula Science.

Human milk contains a plethora of nutrients and bioactive components to help nourish the developing neonate and is considered the "gold standard" for early life nutrition-as befits the only food "designed" by evolution to feed human infants. Over the past decade, there is considerable evidence that highlights the "intelligence" contained in milk components that contribute to infant health beyond basic nutrition-in areas such as programming the developing microbiome and immune system and protecting against infection. Such discoveries have led to new opportunities for infant milk formula (IMF) manufacturers to refine nutritional content in order to simulate the functionality of breast milk. These include the addition of specialized protein fractions as well as fatty acid and complex carbohydrate components-all of which have mechanistic supporting evidence in terms of improving the health and nutrition of the infant. Moreover, IMF is the single most important dietary intervention whereby the human microbiome can be influenced at a crucial early stage of development. In this respect, it is expected that the complexity of IMF will continue to increase as we get a greater understanding of how it can modulate microbiota development (including the development of probiotics, prebiotics, and synbiotics) and influence long-term health. This review provides a scientific evaluation of key features of importance to infant nutrition, including differences in milk composition and emerging "humanized" ingredients.

Immunohistochemical expression of the nicotinic acetylcholine receptor (nAChR) subunits in the human placenta, and effects of cigarette smoking and preeclampsia.

INTRODUCTION: Cigarette smoking (CS) and preeclampsia (PE), regulate the expression of nicotinic acetylcholine receptor (nAChR) subunits in the placenta, yet no data exist at the histological level. METHODS: Using immunohistochemistry of formalin fixed and paraffin embedded placental tissue, this study quantified the expression of nine nAChR subunits (α2, α3, α4, α5, α7, α9, ß1, ß2, δ) and compared the expression amongst four groups of non-smoker non-PE (controls, n = 8), smokers (n = 8), PE (n = 8), and those who were smokers with PE (smoke + PE, n = 4). Quantification was of the percentage of villi with positive cells stained (% villi with +ve), percentage of positive stained cells per villous (% +ve cells/villous), percentage of positive cells in the decidua (%+ve Decidua), and intensity of staining in the outer villous trophoblast layer. RESULTS: Changes were restricted to the villi (as opposed to the decidua), and were specific to the α9 (smoke + PE), ß1 (smokers), and ß2 (PE) subunits when compared to controls. CS seemed to have a protective effect for the ß2 subunit and an additive effect for the α9 and ß1 subunits within the villous core/stroma cells and not the trophoblast layer. DISCUSSION: These findings support that both CS and PE affect nAChRs in the placenta, but that this is restricted to the villi.

Evidence for Extending Anomalous Miocene Volcanism at the Edge of the East Antarctic Craton.

Using field observations followed by petrological, geochemical, geochronological, and geophysical data we infer the presence of a previously unknown Miocene subglacial volcanic center ~230 km from the South Pole. Evidence of volcanism is from boulders of olivine-bearing amygdaloidal/vesicular basalt and hyaloclastite deposited in a moraine in the southern Transantarctic Mountains. 40Ar/39Ar ages from five specimens plus U-Pb ages of detrital zircon from glacial till indicate igneous activity 25-17 Ma. The likely source of the volcanism is a circular -735 nT magnetic anomaly 60 km upflow from the sampling site. Subaqueous textures of the volcanics indicate eruption beneath ice or into water at the margin of an ice mass during the early Miocene. These rocks record the southernmost Cenozoic volcanism in Antarctica and expand the known extent of the oldest lavas associated with West Antarctic rift system. They may be an expression of lithospheric foundering beneath the southern Transantarctic Mountains.

Placental growth factor and pre-eclampsia.

Placental growth factor (PlGF) is an increasingly important molecule in the prediction, diagnosis and treatment of pre-eclampsia. It has pro-angiogenic effects on the feto-placental circulation and supports trophoblast growth. Mechanisms by which PlGF expression is regulated continue to be investigated. Low circulating PlGF precedes the manifestation of clinical disease in pre-eclamptic pregnancies and intrauterine growth restriction. This suggests that low PlGF is a marker of abnormal placentation, but it remains uncertain whether this is a cause or consequence. Prediction of pre-eclampsia using PlGF is promising and may assist in the targeting of resources to women at highest risk of adverse pregnancy outcomes. Promisingly, experimental animal models of pre-eclampsia have been successfully treated with supplemental PlGF. Treatment of pre-eclampsia with PlGF is a potential therapeutic option requiring further exploration. This review focuses specifically on the role of PlGF in normal and pathological placental development and in the clinical management of pre-eclampsia.

Development, validation and implementation of a quantitative food frequency questionnaire to assess habitual vitamin D intake.

BACKGROUND: A well-designed, validated quantitative food frequency questionnaire (FFQ) could offer an efficient and cost-effective method for assessing habitual vitamin D intake. The present study aimed to describe the development, validation and implementation of a vitamin D FFQ. METHODS: National food consumption survey data obtained from Irish adults (18-64 years) were used to identify foods that contribute 95% of vitamin D intake. A winter-based validation study was carried out for the resulting FFQ in 120 females, including 98 women [mean (SD) 65.0 (7.3) years] and 22 girls [12.2 (0.8) years], using a 14-day diet history (DH) as a comparator. Serum 25(OH)D concentrations were analysed. Validity coefficients were calculated using the method of triads. Cross-classification and Bland-Altman analysis were also performed. RESULTS: Median (interquartile range) vitamin D intakes (including the contribution from nutritional supplements) were 5.4 (3.7) and 3.7 (5.9) µg day(-1) from the FFQ and DH, respectively and intakes of vitamin D from food sources were 3.6 (3.1) and 2.4 (2.2) µg day(-1) . The FFQ and DH classified 86% and 87% of individuals into the same and adjacent thirds of wintertime serum 25(OH)D status, respectively. There was a strong association (r = 0.71, P < 0.0001) and no significant systematic or proportional bias observed for the difference between estimates from the FFQ and DH. The validity coefficient for the FFQ was 0.92 (95% confidence interval = 0.80-0.97). Repeatability analysis (n = 56) performed 6-12 months later showed no significant difference in estimates of vitamin D between administrations. CONCLUSIONS: The data obtained in the present study indicate high validity and good reproducibility of a short, interviewer-administered FFQ for vitamin D.

Nitric oxide (NO) reversed TNF-α inhibition of trophoblast interaction with endothelial cellular networks.

INTRODUCTION: The interaction between trophoblast cells and maternal uterine endothelium is important for placental vascular modelling. Nitric oxide (NO) is a potent vasorelaxant that regulates systemic blood pressure and is reduced in preeclampsia. NO may affect placental cell interaction. OBJECTIVES: This study was to examine whether NO plays a role in regulating TNF-α induced inhibition of trophoblast cell integration into endothelial cellular networks in-vitro. METHODS: Red fluorescent-labelled human uterine myometrial microvascular endothelial cells (UtMVECs) were seeded on Matrigel. After endothelial cellular networks formed, green fluorescent-labelled HTR-8/SVneo trophoblast cells were co-cultured with endothelial cells, together with/without TNF-α (0.5 ng/ml) and/or NO donor, sodium nitroprusside dihydrate (SNP) (100 µM). Images were captured after 24 h. The effects on HTR-8/SVneo cell integration were quantified by Image Analysis software. The cells were then recovered from Matrigel to extract mRNA. Quantitative PCR was performed to evaluate the expression of eNOS, VCAM-1 and E-selectin. The concentrations of sVCAM-1 and sE-selectin in the conditioned medium were measured by ELISA. RESULTS: TNF-α inhibited HTR-8/SVneo trophoblast cell integration into endothelial cellular networks, as well as decreased eNOS mRNA expression. Increases in VCAM-1 and E-selectin in cellular mRNA and protein concentrations in the conditioned medium were also seen. The NO donor reversed the inhibitory effect of TNF-α on trophoblast integration and increased eNOS mRNA expression. SNP also reduced sE-selectin and sVCAM-1 expressions which were increased by TNF-α in the conditioned medium. CONCLUSION: Our data suggest the inhibitory effect of TNF-α on trophoblast integration may be mediated by NO, via reducing endothelial cell activation.

The expression of placental soluble fms-like tyrosine kinase 1 in mouse placenta varies significantly across different litters from normal pregnant mice.

OBJECTIVE: Gene expression studies often pool tissues from multiple placentas when using animal models of preeclampsia without accounting for the potential confounders of litter origin or pup sex. We aimed to determine whether placental gene expression differs based on sex or litter. METHODS: We examined the differential expression of soluble fms-like tyrosine kinase 1 (Flt-1) using 35 pups from six normal pregnant mice. RESULTS: Expression of sFlt-1 (p = 0.003) was significantly different between litters but not between sexes (p = 0.17). CONCLUSIONS: These findings highlight the importance of adequate sampling from multiple litters in expression studies when using animal models in clinical research.

Cigarette smoking during pregnancy regulates the expression of specific nicotinic acetylcholine receptor (nAChR) subunits in the human placenta.

Smoking during pregnancy is associated with low birth weight, premature delivery, and neonatal morbidity and mortality. Nicotine, a major pathogenic compound of cigarette smoke, binds to the nicotinic acetylcholine receptors (nAChRs). A total of 16 nAChR subunits have been identified in mammals (9 α, 4 ß, and 1 δ, γ and ε subunits). The effect of cigarette smoking on the expression of these subunits in the placenta has not yet been determined, thus constituting the aim of this study. Using RT-qPCR and western blotting, this study investigated all 16 mammalian nAChR subunits in the normal healthy human placenta, and compared mRNA and protein expressions in the placentas from smokers (n = 8) to controls (n = 8). Our data show that all 16 subunit mRNAs are expressed in the normal, non-diseased human placenta and that the expression of α2, α3, α4, α9, ß2 and ß4 subunits is greater than the other subunits. For mRNA, cigarette smoke exposure was associated with increased expression of the α9 subunit, and decreased expression of the δ subunit. At the protein level, expression of both α9 and δ was increased. Thus, cigarette smoking in pregnancy is sufficient to regulate nAChR subunits in the placenta, specifically α9 and δ subunits, and could contribute to the adverse effects of vasoconstriction and decreased re-epithelialisation (α9), and increased calcification and apoptosis (δ), seen in the placentas of smoking women.

The effect of dietary n-3 polyunsaturated fatty acids supplementation of rams on semen quality and subsequent quality of liquid stored semen.

The objective of this study was to examine the effect of dietary n-3 polyunsaturated fatty acid (PUFA) supplementation of rams on semen quality and subsequent sperm function of liquid stored semen. Mature rams of proven fertility were individually housed and were blocked according to breed, body weight, and body condition score and randomly allocated within block to one of two dietary treatments (N = 7 per treatment). Rams were offered a base diet of hay and concentrate, with the concentrate enriched with either: (1) saturated palmitic acid (CON) or (2) high n-3 PUFA fish oil (FO) supplements. Both lipid supplements were added at 2% (wt/wt) of the total diet as fed and both were partially rumen-protected. The animals were fed their respective diets for a total of 9 weeks and blood samples were collected on weeks 0 (pre-experimental), 4, and 9, relative to initial allocation of diet (week 0), for measurement of plasma concentration of fatty acids, metabolites, insulin like growth factor 1 (IGF-1) and insulin. Semen was collected from each ram (on 1 day in each week) in weeks 4, 5, 7, 8, and 9, and each ejaculate was assessed for volume, wave motion, and concentration of sperm, after which it was diluted in a skim milk-based extender and stored at 4 °C. A second ejaculate was collected on weeks 4, 7, and 9, centrifuged, and the sperm frozen for subsequent lipid analysis. A sample of semen from each ram was assessed at 24, 48, and 72 hours after collection for sperm progressive linear motion, ability to penetrate artificial mucus, and the ability to resist lipid peroxidation (at 24 and 48 hours only) using the thiobarbituric acid reactive substances assay. There was no effect of diet on plasma insulin concentrations or on any of the metabolites measured, however, there was a diet by week interaction for plasma IGF-1 concentration (P < 0.05). This was manifested as the FO supplemented rams having higher IGF-1 concentrations on week 9 compared with the control treatment (P < 0.05), but not at the earlier sampling dates. Compared with the pre-experimental values, supplementation with FO increased plasma concentrations of total n-3 PUFAs by 3.1-fold and decreased n-6 PUFA concentrations by 1.84-fold. Consequently, the ratio of n-6 to n-3 PUFA was decreased in the FO-supplemented rams (P < 0.001). Dietary supplementation with FO increased the concentration of eicosapentaenoic acid in sperm from week 4 to 9 by 2.7-fold (P < 0.05) leading to a 1.5-fold increase in total n-3 PUFA in the same period. Ejaculates collected from rams supplemented with FO yielded a higher semen concentration (P < 0.05), however, there was no difference between diets on any of the other semen quality parameters including semen volume, wave motion, progressive linear motion, ability to penetrate artificial mucus, or ability to resist lipid peroxidation. In conclusion, dietary supplementation of rams with n-3 PUFA successfully increased the n-3 PUFA content of plasma and sperm but has limited effects on the quality of liquid stored semen.

The effect of strategic supplementation with trans-10,cis-12 conjugated linoleic acid on the milk production, estrous cycle characteristics, and reproductive performance of lactating dairy cattle.

The objective was to determine the effects of a protected (lipid-encapsulated) conjugated linoleic acid (LE-CLA) supplement on milk production, estrous cycle characteristics, and reproductive performance in lactating dairy cows on a pasture-based diet. Spring calving dairy cows (n=409) on a single pasture-based commercial dairy farm were used in a completely randomized block design. Cows were assigned to 1 of 2 dietary supplements [LE-CLA (n=203) or no supplement (control, n=206)]. The LE-CLA cows received 51 g/d of a lipid supplement containing 5 g of both trans-10,cis-12 and cis-9,trans-11 CLA from 0 to 60 d in milk. Milk samples were collected 3 times weekly, and each sample was analyzed for progesterone to determine the interval to first ovulation and estrous cycle characteristics. Milk yield and concentrations of fat, protein, and lactose were measured every 2 wk. Cows were inseminated following visual observation of estrus. The breeding season commenced on April 8, 2009 and continued for 16 wk. Transrectal ultrasonography was carried out at 30 to 36 d and 60 to 66 d post-AI to diagnose pregnancy. The LE-CLA treatment resulted in a decrease in milk fat concentration (36.9±0.06 g/kg vs. 30.7±0.06 g/kg for control and LE-CLA, respectively) and yield (0.91±0.02 kg/d vs. 0.84±0.02 kg/d for control and LE-CLA, respectively); however, milk yield was increased by LE-CLA supplementation (24.7±0.7 kg/d vs. 27.2±0.7 kg/d for control and LE-CLA, respectively), resulting in no overall difference in milk energy output. No effect of LE-CLA was observed on any estrous cycle characteristics or measures of reproductive performance. These results support that in pasture-based systems of dairy production, where energy intake limits milk production, energy spared by CLA-induced milk fat depression is partitioned toward increasing milk yield rather than toward body reserves.

Effect of supplementation with different fat sources on the mechanisms involved in reproductive performance in lactating dairy cattle.

Supplementary fat positively influences reproductive performance in dairy cattle, although the mechanisms involved are not clearly defined. Our objective was to determine the effects of four different fat supplements on follicle development, plasma steroid hormone concentrations and prostaglandin (PG) synthesis in lactating dairy cattle. Forty-eight early lactation Holstein-Friesian cows (21 primiparous, 27 multiparous) were used in a completely randomized block design. Cows were fed the same basal TMR diet and received one of four fat supplements: (i) palmitic acid (18:0 fatty acid; Control), (ii) flaxseed (rich in 18:3 n-3 fatty acid; Flax), (iii) conjugated linoleic acid (a mixture of cis-9, trans-11 and trans-10, cis-12 isomers; CLA), and (iv) fish oil (rich in 20:5 and 22:6 n-3 fatty acids; FO). All lipid supplements were formulated to be isolipidic; palmitic acid was added as necessary to provide a total lipid supplement intake of 500 g/day. Cows were synchronized to be in estrus on Day 15 of dietary treatment. All antral follicles were counted, and dominant follicles, subordinate follicles and corpora lutea were measured daily via transrectal ovarian ultrasonography for one complete estrous cycle. Blood samples were collected daily, and selected samples were analyzed for progesterone, estradiol, insulin-like growth factor-1, insulin, cholesterol and non-esterified fatty acids. Estrus was synchronized a second time, and liver and endometrial biopsies were collected on Day 7 of the estrous cycle. Gene expression was evaluated for a number of genes involved in prostaglandin synthesis (endometrium) and fatty acid uptake and utilization (liver). Fat supplementation had little effect on follicle development. Cows receiving supplementary n-3 fatty acids had lesser plasma progesterone (P4) and smaller corpora lutea than cows receiving the CLA or Control supplements. Effects of fat supplementation on the endometrial expression of genes involved in PG synthesis were minor. Hepatic expression of SREBF1, ASCL1 and FABP1 was reduced by FO supplementation. Reduced plasma P4 in n-3 supplemented cows may lead to a suboptimal uterine environment for embryo development and hence reduced fertility compared to cows receiving the control or CLA supplements.

OS010. Use of retinal imaging to characterise physiological vascularchanges throughout pregnancy.

INTRODUCTION: Visualisation of the microcirculation through retinal imaging can provide information on the health of systemic vasculature. Characterisation of the retinal vasculature throughout pregnancy using retinal imaging is a novel approach to examine physiological changes to the cardiovascular system, and may be useful to predict early pathophysiological signs of adverse maternal outcomes. OBJECTIVES: To characterise the retinal vascular and blood pressure (BP) changes that occur throughout a healthy pregnancy. METHODS: Data was collected from women recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and BP readings were collected throughout pregnancy. Postnatal data was collected from medical records, and women with hypertensive disorders of pregnancy and gestational diabetes mellitus were excluded. This left a final group of 19 women. Retinal images from 13±2, 19±2, 29±2 and 38±2 weeks gestation were graded using semi-automated retinal vascular calibre measurement (IVAN) software and the central retinal arteriolar equivalent (CRAE), and central retinal venular equivalent (CRVE). BP data was collected at the same time points as the retinal images. Analysis of data was performed using paired t-tests and repeated measures analysis of variance (ANOVA). Women with missing data points were excluded from the analysis at the relevant time points. RESULTS: Over the course of pregnancy, there was a significant dilatation of retinal arterioles between 13±2 and 19±2weeks (from 166.4 to 172.7µm, SE: 3.7µm, n=19, p=0.01), corresponding to a significant fall in diastolic BP during this time (from 64.6 to 60.2mmHg, SE: 1.5mmHg, p=0.01). No significant changes in venular diameter or systolic BP were noted. Between 19±2 and 29±2weeks (n=4), no significant changes to retinal arteriolar or venular diameter were seen although there were significant increases in both systolic and diastolic BP (SBP: from 100.3 to 109.9mmHg, SE: 1.9mmHg, p=0.01; DBP: from 59.3 to 64.6mmHg, SE: 6.9mmHg, p=0.01). Between 29±2 and 38±2weeks (n=3), no significant changes in retinal arteriolar, and venular diameter or BP were observed. CONCLUSION: An increase in retinal arteriolar diameter between 13±2 and 19±2 weeks gestation was observed, which corresponded to a decrease in both systolic and diastolic BP. However, between 19±2 and 29±2 weeks there was no change in vasculature, even though there was a significant increase in BP. By characterising the changes to retinal vessels that occur throughout a healthy pregnancy, we can further our understanding of the response of the systemic vasculature to pregnancy, which may provide clues to early vascular disease of pregnancies.

OS016. Retinal vascular changes in hypertensive disorders of pregnancy.

INTRODUCTION: Hypertensive disorders of pregnancy (HDP) are characterised by vascular dysfunction. Retinal vascular imaging is a novel, non-invasive way to characterise early microvascular changes in pregnancy, and as a result has the potential to be used to predict the onset of HDP. OBJECTIVES: To characterise retinal vascular changes that occur in HDP, and compare these changes to those in healthy pregnancies. METHODS: Women were recruited at 13±2 weeks of gestation from Royal Prince Alfred Hospital, a major metropolitan tertiary referral hospital in Sydney, Australia. Retinal images centred on the optic disc and blood pressure (BP) readings were collected at 13±2, 19±2, 29±2 and 38±2 weeks gestation. Retinal images were graded using semi-automated retinal vascular calibre measurement software (IVAN) and the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) were calculated. Within and between subject repeat measures analysis was performed on images from each trimester, using paired t-tests and repeated measures analysis of variance (ANOVA). Multiple linear regressions were used to model the average arteriole diameter adjusted for age, tobacco consumption and body mass index (BMI). All tests were two-sided using a 5% level of significance. A clinical diagnosis of HDP was obtained from postnatal medical record data. Women with missing data points were excluded from the analysis at that time point. RESULTS: Of the 39 women included in the study, 6 (15%) were diagnosed with HDP. In the HDP cohort, repeated measures ANOVA revealed no significant changes in arteriolar or venular diameter measurements throughout pregnancy. Paired t-tests indicated no significant differences in any of the outcome measures between HDP and healthy pregnancies at 13±2 (n=36) and 19±2 (n=39)weeks. At 29±2weeks (n=39), there was a significantly smaller venular diameter in HDP pregnancies (220.4±6.9µm vs 239.1± 5.4µm in healthy pregnancies, p=0.03). At 38±2weeks (n=39), arteriolar diameter was significantly smaller in HDP pregnancies (148.6±6.0µm vs 164.1±4.6µm in healthy pregnancies, p=0.04). Similar results persisted following adjustments for cardiovascular risk factors (age, tobacco use and BMI). CONCLUSION: Significant differences in the retinal vasculature develop in HDP as compared to healthy pregnancies. These differences appear at29±2weeks gestation and persist throughout the rest of the pregnancy. Retinal vascular imaging is a promising tool for the detection of the early microvascular changes in HDP, prior to diagnosis.

OS041. Apolipoprotein A-I protects normal integration of the trophoblast into endothelial cellular networks in an in vitro model of preeclampsia.

INTRODUCTION: Failure of the trophoblast to appropriately invade uterine spiral arteries is thought to be an initiating event in preeclampsia, a disorder associated with endothelial dysfunction. A dyslipidemia characterised by low plasma levels of high density lipoproteins (HDL) and elevated triglycerides has also been described in preeclampsia. The pro-inflammatory cytokine TNF-α inhibits trophoblast invasion of uterine endothelial cells. Previous work using an in vitro JEG-3 cell/Uterine endothelial cell co-culture model investigated the effect of apoliopoprotein A-I, the main apolipoprotein component of HDL, on trophoblast incorporation into endothelial tubules in the presence and absence of TNF-α. These effects are now investigated using the human invasive trophoblast cell line HTR-8/SVneo. OBJECTIVES: This study asks if apoA-I, which has established anti-inflammatory properties, can protect against the deleterious effect of TNF-α on trophoblast-endothelial cell interactions. METHODS: The in vitro trophoblast-uterine endothelial cell co-culture model was used to investigate the effect of apoA-I on trophoblast incorporation into endothelial tubules in the presence and absence of TNF-α. Uterine endothelial cells were pre-incubated with lipid free apoA-I (final apoA-I concentration 1 mg/mL) for 16h prior to seeding on matrigel coated plates. Tubules formed within 4h. Fluorescence-labelled HTR-8/SVneo trophoblast cells were then co-cultured with the endothelial cells±TNF-α (final concentration of 0.2ng/mL). Bright field and fluorescent images were captured after 24h. The effect of TNF-α on HTR-8/SVneo cell invasion was quantified with Image J software. Integration of HTR-8/SVneo trophoblast cells into uterine endothelial tubular networks was also imaged using live cell imaging techniques (Zeiss Axiovert). RESULTS: TNF-α inhibited HTR-8/SVneo (trophoblast) cell integration into endothelial tubular structures by 24.1±3.7% p<0.001. This effect was reversed when the endothelial cells were pre-incubated for 16h with lipid free apoA-I (p<0.001 compared to non-incubated cells). Live cell images of the co-culture clearly demonstrate a disruption to the normal integration of trophoblast into endothelial tubular structures in the presence of TNF-α. The protective effect conferred by pre-incubation of endothelial cells with apoA-I against TNF-α is also clearly visible. CONCLUSION: Apolipoprotein A-I has been shown to enhance trophoblast-endothelial cell integration in the presence of a pro-inflammatory stimulus. A healthy lipid profile may affect pregnancy outcomes by priming endothelial cells in preparation for trophoblast invasion.

OS044. Morphological differences in murine placenta detected by magneticresonance imaging measurements of T2 relaxation times in mouse models ofpreeclampsia.

INTRODUCTION: We have demonstrated that morphologically distinct regions of the murine placenta can be detected by magnetic resonance imaging (MRI), with image contrast arising from the variation in T2 relaxation times between regions and dependent upon blood flow. Previous studies of human placenta by other groups have shown a homogeneous tissue with correlation of relaxation times with gestational age and a trend for shorter relaxation times in pregnancies complicated by preeclampsia and fetal growth restriction. The ability to detect morphological changes and alterations in blood flow in experimental models of preeclampsia would be a significant boost in understanding the relationship between abnormal placental implantation, reduced placental perfusion, inflammatory cytokines, angiogenic molecules and other factors that may play a role in the syndrome. OBJECTIVES: The aim of this study was to investigate whether morphological changes or abnormalities can be detected by T2 mapping in the placenta of mice subject to two experimental models of preeclampsia (reduced uterine perfusion pressure (RUPP) model and TNF-α induced model). METHODS: Pregnant C57BL/6JArc mice were, on day 13.5 of gestation, either subject to a unilateral ligation of the right uterine artery (RUPP) (n=2) or given an infusion of TNF-α by subcutaneous insertion of a mini-osmotic pump primed to deliver 500ng/kg/day for 4days (n=2). Controls were normal pregnant (n=2), sham-operated (n=1) or saline infused animals(n=1). MRI images were acquired on anaesthetised mice on day 17.5 of gestation using a Bruker Avance 11.7 Tesla wide-bore spectrometer with micro-imaging probe capable of generating gradients of 0.45T/m. T2 measurements were acquired using an MSME sequence protocol (Bruker MSME-T2-map) with an in-plane resolution of 0.1-0.2mm. Matlab was used to generate R2 (i.e.,1/T2) maps from the acquired data with the T2 values being calculated from selected regions of interest from 2-6 individual placenta from each mouse. RESULTS: Differences in the pattern of the regions of T2 contrast in the placenta were observed between normal, TNF-α treated and RUPP mice. The ratio of T2 values from the inner two regions was also significantly altered in TNF-α treated 1.98±0.09 (p=0.007); RUPP 1.94±0.11 (p=0.006) compared to normal animals 2.5±0.1 . CONCLUSION: These results demonstrate that morphological differences or abnormalities can be detected by T2 mapping in the placenta of mice subject to experimental models of preeclampsia and may be used to analyse changes quantitatively. This technology has the potential to be used when studying the dynamic changes in the placenta of pregnancies complicated by preeclampsia.