1,721,038 research outputs found
Placental Related Disorders of Pregnancy
No full textThe Special Issue “Placental Related Disorders of Pregnancy” was edited by Dr Hiten D. Mistry, Department of Women and Children's Health, School of Life Course and Population Health Sciences, King's College London, London, UK and Dr Eun D. Lee, Department of Obstetrics and Gynecology, Virginia Commonwealth University Health System, Richmond, VA, USA
Blood pressure measurement and adverse pregnancy outcomes: a cohort study testing blood pressure variability and alternatives to 140/90 mmHg
No full textObjective: To examine the association with adverse pregnancy outcomes of: (1) American College of Cardiology/American Heart Association blood pressure (BP) thresholds, and (2) visit-to-visit BP variability (BPV), adjusted for BP level. Design: An observational study. Setting: Analysis of data from the population-based UK Southampton Women's Survey (SWS). Population or sample: 3003 SWS participants. Methods: Generalised estimating equations were used to estimate crude and adjusted relative risks (RRs) of adverse pregnancy outcomes by BP thresholds, and by BPV (as standard deviation [SD], average real variability [ARV] and variability independent of the mean [VIM]). Likelihood ratios (LRs) were calculated to evaluate diagnostic test properties, for BP at or above a threshold, compared with those below. Main outcome measures: Gestational hypertension, severe hypertension, pre-eclampsia, preterm birth (PTB), small-for-gestational-age (SGA) infants, neonatal intensive care unit (NICU) admission. Results: A median of 11 BP measurements were included per participant. For BP at ≥20 weeks’ gestation, higher BP was associated with more adverse pregnancy outcomes; however, only BP <140/90 mmHg was a good rule-out test (negative LR <0.20) for pre-eclampsia and BP ≥140/90 mmHg a good rule-in test (positive LR >8.00) for the condition. BP ≥160/110 mmHg could rule-in PTB, SGA infants and NICU admission (positive LR >5.0). Higher BPV (by SD, ARV, or VIM) was associated with gestational hypertension, severe hypertension, pre-eclampsia, PTB, SGA and NICU admission (adjusted RRs 1.05–1.39). Conclusions: While our findings do not support lowering the BP threshold for pregnancy hypertension, they suggest BPV could be useful to identify elevated risk of adverse outcomes.</p
Blood pressure measurement and adverse pregnancy outcomes - a cohort study testing blood pressure variability and alternatives to 140/90mmHg
No full textObjective: to examine the relationship with adverse pregnancy outcomes of: (1) American College of Cardiology/American Heart Association blood pressure (BP) thresholds, and (2) visit-to-visit BP variability (BPV), adjusted for BP level.Design: an observational study.Setting: analysis of data from the population-based UK Southampton Women’s Survey (SWS).Population or Sample: 3003 SWS participants.Methods: generalised estimating equations were used to estimate crude and adjusted relative risks (RRs) of adverse pregnancy outcomes by BP thresholds, and by BPV (as standard deviation [SD], average real variability [ARV], and variability independent of the mean [VIM]). Likelihood ratios (LRs) were calculated to evaluate diagnostic test properties, for BP at or above a threshold, compared with those below.Main Outcome Measures: gestational hypertension, severe hypertension, pre-eclampsia, preterm birth (PTB), small-for-gestational-age (SGA) infants, neonatal intensive care unit (NICU) admission.Results: a median of 11 BP measurements were included per participant. For BP at ≥20 weeks’ gestation, higher BP was associated with more adverse pregnancy outcomes; however, only BP <140/90mmHg was a good rule-out test (negative LR <0.20) for pre-eclampsia, and BP ≥140/90mmHg a good rule-in test (positive LR >8.00) for the condition. BP ≥160/110mmHg could rule-in PTB, SGA infants, and NICU admission (positive LR >5.0). Higher BPV (by SD, ARV, or VIM) was associated with gestational hypertension, severe hypertension, pre-eclampsia, PTB, SGA, and NICU admission (adjusted RRs 1.05-1.39).Conclusions: while our findings do not support lowering the BP threshold for pregnancy hypertension, they suggest BPV could be useful to identify elevated risk of adverse outcomes.<br/
Androgens Tend to Be Higher, but What about Altered Progesterone Metabolites in Boys and Girls with Autism?
Full text linkBackground: Evidence exists that steroid hormones are altered in individuals with autism, especially androgens. Despite lower prevalence in girls than boys, evidence of potential alterations in progesterone metabolites is sparse, so the aim of this study was to elucidate different progesterone metabolites in affected children with autism versus healthy controls. Material and Methods: Circadian urine samples from 48 boys and 16 girls with autism spectrum disorders and a matched case–control group were analysed for progesterone metabolites by gas chromatography–mass spectrometry and normalised for creatinine excretion. Results: In boys with autism, the majority of progesterone metabolites were reduced, such as progesterone, 6a-OH-3a5b-TH-progesterone, or 20a-DH-progesterone (p < 0.01 for all). In girls with autism, a similar pattern of reduction in progesterone metabolites was detected; however, potentially due to the relatively small sample, this pattern was only detectable on the level of a trend. Discussion: As stated, androgen levels are higher in boys and girls with autism, but evidence for progesterone metabolites is much sparser. The pattern of a decrease in progesterone metabolites suggests the existence of an altered routing of steroid metabolites, probably in combination with a dysregulation of the HPAG axis. As, recently, increased CYP17A1 activity has been suggested, the stronger routing towards androgens is further implied in line with our findings of lower progesterone concentrations in boys and girls with autism than healthy controls
Do lower antenatal blood pressure cut-offs in pregnant women with obesity identify those at greater risk of adverse maternal and perinatal outcomes? A secondary analysis of data from the UK Pregnancies Better Eating and Activity Trial (UPBEAT)
No full textBackground: obesity is a major risk-factor for adverse pregnancy outcomes. While the 2017 American College of Cardiology/American Heart Association (ACC/AHA) classification of normal and abnormal blood pressure (BP) outside pregnancy has been suggested for use in pregnancy, the impact on adverse outcomes has not been examined specifically in women with obesity.Methods: the UK Pregnancies Better Eating and Activity Trial (UPBEAT) enroled women with a body mass index (BMI) ≥ 30 kg/m2. In secondary analyses, maximal antenatal BP was categorised by 2017 ACC/AHA criteria: ‘Normal’ BP (systolic [sBP] <120 mmHg and diastolic [dBP] <80 mmHg), ‘Elevated’ BP (sBP 120–129 mmHg and dBP <80 mmHg), ‘Stage 1 hypertension’ (sBP 130–139 mmHg and/or dBP 80-89 mmHg), and ‘Stage 2 hypertension’ (sBP ≥140 mmHg and/or dBP ≥90 mmHg, non-severe [sBP 140-159 mmHg and/or dBP 90–109 mmHg] and severe (sBP ≥160 mmHg and/or dBP ≥110 mmHg). Main outcomes were preterm birth, postpartum haemorrhage (PPH), birthweight <10th centile (small-for-gestational age, SGA), and neonatal intensive care unit (NICU) admission. Associations with adverse outcomes were adjusted for UPBEAT intervention, maternal age, booking BMI, ethnicity, parity, smoking, alcohol, and previous pre-eclampsia or gestational diabetes. Diagnostic test properties (positive and negative likelihood ratios, -LR and +LR) were assessed as individual categories (vs. ‘Normal’ BP), and as threshold values.Results: severe ‘Stage 2 hypertension’ (vs. BP < 160/110 mmHg) was associated with PPH (RR 2.57 (1.35, 4.86)) and SGA (RR 2.52 (1.05, 6.07)) only in unadjusted analyses. No outcomes were associated with ‘Stage 1 hypertension’ or ‘Elevated BP’. All +LR were <5.0 and -LR ≥ 0.20, indicating that no BP threshold was useful as a diagnostic test to detect preterm birth, PPH, SGA, or NICU admission.Conclusions: among pregnant women with obesity, we found no evidence that lowering the antenatal BP considered to be abnormal (from 140/90 mmHg) would assist in identifying women and babies at risk
Evidence for hypoxia-induced dysregulated cholesterol homeostasis in preeclampsia: Insights into the mechanisms from human placental cells and tissues.
Full text linkPreeclampsia (PE) poses a considerable risk to the long-term cardiovascular health of both mothers and their offspring due to a hypoxic environment in the placenta leading to reduced fetal oxygen supply. Cholesterol is vital for fetal development by influencing placental function. Recent findings suggest an association between hypoxia, disturbed cholesterol homeostasis, and PE. This study investigates the influence of hypoxia on placental cholesterol homeostasis. Using primary human trophoblast cells and placentae from women with PE, various aspects of cholesterol homeostasis were examined under hypoxic and hypoxia/reoxygenation (H/R) conditions. Under hypoxia and H/R, intracellular total and non-esterified cholesterol levels were significantly increased. This coincided with an upregulation of HMG-CoA-reductase and HMG-CoA-synthase (key genes regulating cholesterol biosynthesis), and a decrease in acetyl-CoA-acetyltransferase-1 (ACAT1), which mediates cholesterol esterification. Hypoxia and H/R also increased the intracellular levels of reactive oxygen species and elevated the expression of hypoxia-inducible factor (HIF)-2α and sterol-regulatory-element-binding-protein (SREBP) transcription factors. Additionally, exposure of trophoblasts to hypoxia and H/R resulted in enhanced cholesterol efflux to maternal and fetal serum. This was accompanied by an increased expression of proteins involved in cholesterol transport such as the scavenger receptor class B type I (SR-BI) and the ATP-binding cassette transporter G1 (ABCG1). Despite these metabolic alterations, mitogen-activated-protein-kinase (MAPK) signaling, a key regulator of cholesterol homeostasis, was largely unaffected. Our findings indicate dysregulation of cholesterol homeostasis at multiple metabolic points in both the trophoblast hypoxia model and placentae from women with PE. The increased cholesterol efflux and intracellular accumulation of non-esterified cholesterol may have critical implications for both the mother and the fetus during pregnancy, potentially contributing to an elevated cardiovascular risk later in life
COMPARISON OF IN VITRO PRE-ECLAMPSIA (PE) CELL MODELS WITH PE PLACENTAL TISSUE
No full textObjectives: We induced hypoxia and oxidative stress (OS) in cytotrophoblasts
(CTB) from control placentae to mimic the characteristics of preeclampsia
(PE). For validation we compared the gene and protein
expression of established PE biomarkers between the cell models and PE
placentae.
Methods: CTB isolated from healthy term placentae (n¼2) were cultured
either under normoxic (5% pCO2;21% pO2;24h), hypoxic (5% pCO2;1.5%
pO2;24h) or OS (consecutive 6h-intervals of normoxia and hypoxia until
24h) conditions. mRNA abundances of PE biomarkers (Table1) were analysed
by qRT-PCR in the cell models and PE placentae (n¼12). Additionally,
the secretion of sFlt1 and PlGF was determined by ELISA in cell culture
supernatants. Statistical analysis was performed using unpaired t-test.
Results: The cell models recapitulated important pathophysiological
changes occurring in PE (Table1) including the upregulation of sFlt1 which
was also observed in PE placentae. Interestingly, in the cell models the
sFlt1/PlGF ratio was above the clinically applied cutoff value of 38 for
hypoxic (77.3±35.2) and OS (124±88.3), but <38 for normoxic (19.4±16)
conditions.
nm-not measured
Conclusion: The established cell models are mimicking important characteristics
of PE. The sFlt1/PlGF ratio obtained in cell models is in agreement
with reports proposing sFlt1/PlGF as predictive diagnostic marker for
PE. Thus, hypoxia and OS induced in primary CTB can serve as suitable
models to study the detailed mechanisms of PE
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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