Search Results Heading

MBRLSearchResults

mbrl.module.common.modules.added.book.to.shelf
Title added to your shelf!
View what I already have on My Shelf.
Oops! Something went wrong.
Oops! Something went wrong.
While trying to add the title to your shelf something went wrong :( Kindly try again later!
Are you sure you want to remove the book from the shelf?
Oops! Something went wrong.
Oops! Something went wrong.
While trying to remove the title from your shelf something went wrong :( Kindly try again later!
    Done
    Filters
    Reset
  • Discipline
      Discipline
      Clear All
      Discipline
  • Is Peer Reviewed
      Is Peer Reviewed
      Clear All
      Is Peer Reviewed
  • Item Type
      Item Type
      Clear All
      Item Type
  • Subject
      Subject
      Clear All
      Subject
  • Year
      Year
      Clear All
      From:
      -
      To:
  • More Filters
93 result(s) for "Vatish, Manu"
Sort by:
Predictive Value of the sFlt-1:PlGF Ratio in Women with Suspected Preeclampsia
This study involving women with suspected preeclampsia showed that an sFlt-1:PlGF ratio of 38 or less has a very high negative predictive value for the development of preeclampsia in the next week and thus may be clinically useful. Preeclampsia, a heterogeneous, multisystem disorder defined by the new onset of hypertension and proteinuria after 20 weeks of gestation, affects 2 to 5% of pregnancies worldwide. 1 – 5 Preeclampsia is associated with high risks of iatrogenic preterm delivery, intrauterine growth restriction, placental abruption, and perinatal mortality, along with maternal morbidity and mortality. 6 , 7 The cause of preeclampsia is incompletely understood, but the disorder is thought to be due to placental malperfusion resulting from abnormal remodeling of maternal spiral arteries. 8 , 9 In preeclampsia, circulating maternal serum levels of soluble fms-like tyrosine kinase 1 (sFlt-1) are increased, and placental growth factor (PlGF) levels . . .
PatchCTG: A Patch Cardiotocography Transformer for Antepartum Fetal Health Monitoring
Antepartum Cardiotocography (CTG) is a biomedical sensing technology widely used for fetal health monitoring. While the visual interpretation of CTG traces is highly subjective, with the inter-observer agreement as low as 29% and a false positive rate of approximately 60%, the Dawes–Redman system provides an automated approach to fetal well-being assessments. However, it is primarily designed to rule out adverse outcomes rather than detect them, resulting in a high specificity (90.7%) but low sensitivity (18.2%) in identifying fetal distress. This paper introduces PatchCTG, an AI-enabled biomedical time series transformer for CTG analysis. It employs patch-based tokenisation, instance normalisation, and channel-independent processing to capture essential local and global temporal dependencies within CTG signals. PatchCTG was evaluated on the Oxford Maternity (OXMAT) dataset, which comprises over 20,000 high-quality CTG traces from diverse clinical outcomes, after applying the inclusion and exclusion criteria. With extensive hyperparameter optimisation, PatchCTG achieved an AUC of 0.77, with a specificity of 88% and sensitivity of 57% at Youden’s index threshold, demonstrating its adaptability to various clinical needs. Its robust performance across varying temporal thresholds highlights its potential for both real-time and retrospective analysis in sensor-driven fetal monitoring. Testing across varying temporal thresholds showcased it robust predictive performance, particularly with finetuning on data closer to delivery, achieving a sensitivity of 52% and specificity of 88% for near-delivery cases. These findings suggest the potential of PatchCTG to enhance clinical decision-making in antepartum care by providing a sensor-based, AI-driven, objective tool for reliable fetal health assessment.
Melanin Nanoparticles as a Safe and Effective Iron Chelation Therapy: An ex vivo Assessment of Human Placental Transfer in Pregnant Beta-Thalassemia
Iron toxicity is a major contributor to adverse pregnancy outcomes in women with transfusion-dependent thalassemia. Currently used iron chelators are not recommended during pregnancy, as they can cross the placenta causing potential risk to the fetus. However, ceasing medication may adversely affect the mother's health in both the short- and long-term. We previously demonstrated that melanin nanoparticles can effectively chelate iron, and this has been confirmed by others in iron-overloaded mice. This study aims to assess whether these nanoparticles cross the placenta and evaluate their biocompatibility and haemocompatibility. A library of 50 nm, 200 nm, and 500 nm melanin nanoparticles were synthesized and coated with Polyethylene Glycol (PEG) to improve their stability. The particles were tested for chelating iron efficacy in and biocompatibility. An in vitro BeWo (choriocarcinoma) cell model and ex vivo human placental perfusion system were used to assess nanoparticle transplacental passage. Melanin nanoparticles of all sizes were able to chelate iron with a maximum adsorption of 14 mm iron/g of material; significantly higher than Desferrioxamine (DFO) of the same concentration. It was also determined that PEGylated melanin nanoparticles with appropriate size (cut off 200 nm) could be restricted from passing across the placental barrier in an in vitro model using a human choriocarcinoma cell line and in an ex vivo human placental perfusion model. The particles did not cause red cell haemolysis or blood clotting at concentrations up to 1 mM. It was demonstrated herein that transport of MNPs across the placental barrier is highly dependent on particle size (cut off size of 200 nm PEGylated MNPs). Findings suggest the possibility of providing a safe method of iron chelation during pregnancy. Future work using in vivo models will be applied to study systemic particle interactions.
Cardiac-specific troponins in uncomplicated pregnancy and pre-eclampsia: A systematic review
The risk of myocardial infarction (MI) increases during pregnancy, particularly in women with pre-eclampsia. MI is diagnosed by measuring high blood levels of cardiac-specific troponin (cTn), although this may be elevated in women with pre-eclampsia without MI, which increases diagnostic uncertainty. It is unclear how much cTn is elevated in uncomplicated and complicated pregnancy, which may affect whether the existing reference intervals can be used in pregnant women. Previous reviews have not investigated high-sensitivity troponin in pregnancy, compared to older, less sensitive methods. Electronic searches using the terms \"troponin I\" or \"troponin T\", and \"pregnancy\", \"pregnancy complications\" or \"obstetrics\". cTn levels were extracted from studies of women with uncomplicated pregnancies or pre-eclampsia. The search identified ten studies with 1581 women. Eight studies used contemporary methods that may be too insensitive to use reliably in this clinical setting. Two studies used high-sensitivity assays, with one reporting an elevation in troponin I (TnI) in pre-eclampsia compared to uncomplicated pregnancy, and the other only examining women with pre-eclampsia. Seven studies compared cTn between women with pre-eclampsia or uncomplicated pregnancy using any assay. Seven studies showed elevated TnI in pre-eclampsia compared to uncomplicated pregnancy or non-pregnant women. One study measured troponin T (TnT) in pregnancy but did not examine pre-eclampsia. TnI appears to be elevated in pre-eclampsia, irrespective of methodology, which may reflect the role of cardiac stress in this condition. TnI may be similar in healthy pregnant and non-pregnant women, but we found no literature reporting pregnancy-specific reference intervals using high-sensitivity tests. This limits broader application of cTn in pregnancy. There is a need to define reference intervals for cTn in pregnant women, which should involve serial sampling throughout pregnancy, with careful consideration for gestational age and body mass index, which cause dynamic changes in normal maternal physiology.
Exosomal microRNA profiling in early and late onset preeclamptic pregnant women reflects pathophysiology
Preeclampsia is the leading cause of maternal and fetal mortality due to the inability to diagnose and treat the disorder early in pregnancy. This is attributed to the complex pathophysiology and unknown etiology of the disorder, which is modulated by several known and unknown factors. Exosomes have recently been implicated as possible mediators of the pathogenesis of preeclampsia, with, however, no evidence linking these nanovesicles to the pathophysiology of preeclampsia and its subtypes. To better understand the pathophysiological role of exosomes in preeclampsia, we have analyzed the exosomal microRNA in early and late onset preeclamptic women in comparison to their gestationally matched normotensive controls using Digital Direct Detection (NanoString Technologies). For the first time, distinct exosomal microRNA signatures in early and late onset preeclampsia have been identified. Moreover, these signatures indicate that exosomes are involved in key pathological features associated with preeclampsia and differentiate between the subtypes. This study forms the basis for the diagnostic and functional validation of the identified signatures as biomarkers of preeclampsia and its subtypes.
The sFlt1/PlGF ratio predicts faster fetal deterioration in early fetal growth restriction: A historical cohort study
Introduction The velocity of fetal deterioration in fetal growth restriction is extremely variable, which makes monitoring and counseling very challenging. The soluble fms‐like tyrosine kinase to placental growth factor (sFlt1/PlGF) ratio provides a readout of the vasoactive environment that correlates with preeclampsia and fetal growth restriction and that could be useful to predict fetal deterioration. Previous studies showed a correlation between higher sFlt1/PlGF ratios and lower gestational ages at birth, although it is unclear whether this is due to the increased incidence of preeclampsia. Our goal was to evaluate whether the sFlt1/PlGF ratio predicts faster fetal deterioration in early fetal growth restriction. Material and methods This was a historical cohort study in a tertiary maternity hospital. Data from singleton pregnancies with early fetal growth restriction (diagnosed before 32 gestational weeks) confirmed after birth monitored between January 2016 and December 2020 were retrieved from clinical files. Cases of chromosomal/fetal abnormalities, infection and medical terminations of pregnancy were excluded. The sFlt1/PlGF ratio was acquired at diagnosis of early fetal growth restriction in our unit. The correlation of log10 sFlt1/PlGF with latency to delivery/fetal demise was assessed with linear, logistic (positive sFlt1/PlGF if >85) and Cox regression excluding deliveries for maternal conditions and controlling for preeclampsia, gestational age at time of ratio test, maternal age and smoking during pregnancy. Receiver‐operating characteristic (ROC) analysis tested the performance of sFlt1/PlGF ratio in predicting delivery for fetal reasons in the following week. Results 125 patients were included. Mean sFlt1/PlGF ratio was 91.2 (SD 148.7) and 28% of patients had a positive ratio. A higher log10 sFlt1/PlGF ratio predicted shorter latency for delivery/fetal demise in linear regression after controlling for confounders, β = −3.001, (−3.713 to −2.288). Logistic regression with ratio positivity confirmed these findings (latency for delivery 5.7 ± 3.32 weeks for ratios ≤85 vs 1.9 ± 1.52 weeks for ratios >85); β = −0.698 (−1.064 to −0.332). Adjusted Cox regression showed that a positive ratio confers a significantly positive hazard ratio (HR) for earlier delivery/fetal demise, HR 9.869 (5.061–19.243). ROC analysis showed an area under the curve of 0.847 (SE ± 0.06). Conclusions sFlt1/PlGF ratio is correlated with faster fetal deterioration in early fetal growth restriction, independently of preeclampsia. A higher sFlt1/PlGF ratio at diagnosis of early fetal growth restriction predicts a shorter latency to delivery/fetal demise after controlling for maternal‐indicated deliveries, preeclampsia, gestational age at time of ratio test, maternal age and smoking.
Identifying High-Risk Pre-Term Pregnancies Using the Fetal Heart Rate and Machine Learning
Fetal heart rate (FHR) monitoring is ubiquitous in antenatal care, yet human visual interpretation poorly predicts adverse pregnancy outcomes. Meanwhile, preterm gestations carry a high burden of stillbirth and severe fetal compromise, where earlier identification of high-risk pregnancies may justify iatrogenic preterm delivery to prevent avoidable fetal death. We analyzed 4867 antepartum FHR recordings from pre-term pregnancies meeting at least one of ten adverse outcome criteria alongside 4014 term uncomplicated controls. Seven clinically validated FHR features were extracted from each trace, and six machine-learning classifiers were trained on 80% of the data (7105 samples) using k-fold cross-validation; the remaining 20% (1776 samples) formed an internal validation cohort. The random forest demonstrated the best performance, achieving an area under the receiver-operating characteristic curve (AUC) of 0.88 (95% confidence interval [CI] 0.87–0.88) during training and 0.88 (95% CI 0.86–0.90) on validation, with good calibration (Brier score 0.14). Median AUC across individual adverse outcomes was 0.85 (interquartile range [IQR] 0.81–0.89) and exceeded 0.80 at all gestational ages assessed; sensitivity and specificity at the Youden threshold were 76.2% and 87.5%, respectively. Decision-curve analysis demonstrated net benefit across a range of clinically relevant probability thresholds. These findings indicate that data-driven interpretation of antepartum FHR can stratify risk in pre-term pregnancies with high accuracy and may support earlier, evidence-based clinical decision-making, particularly in resource-limited settings where specialist expertise is limited.
A new paradigm of islet adaptations in human pregnancy: insights from immunohistochemistry and proteomics
Physiological changes during pregnancy support foetal growth, including adaptations in pancreatic islets to maintain glucose homeostasis. We investigate these adaptations using rare, high-quality pancreatic tissue from pregnant human donors and matched controls. We profile islets from pregnant donors using proteomics and assess α- and β-cell characteristics, as well as prolactin receptor and serotonin 2B receptor expression. Proteomic profiling of microdissected human islets identifies 7546 proteins but shows minimal differences in protein expression. In pregnancy, we show that islet area increases 1.9-fold, α- and β-cell areas increase 4.3- and 1.9-fold, driven by an increase in cell number rather than hypertrophy. Prolactin receptor expression is higher in α but not β cells, and serotonin 2B receptor is undetectable in β cells. Glucagon-like peptide-1 abundance increases 2.9-fold in α cells. These findings indicate that the molecular mechanisms driving pregnancy-induced islet adaptations in humans differ from those in mice, highlighting the need for human-based studies. Here the authors show that human pancreatic islets adapt during pregnancy with increased α-cell area and GLP-1 abundance, while key differences from islet adaptations in mouse pregnancy include unchanged β-cell PRLR abundance and absent β-cell 5-HT 2B receptor expression.
Maternal high fat diet during pregnancy and lactation alters hepatic expression of insulin like growth factor-2 and key microRNAs in the adult offspring
Background miRNAs play important roles in the regulation of gene functions. Maternal dietary modifications during pregnancy and gestation have long-term effects on the offspring, but it is not known whether a maternal high fat (HF) diet during pregnancy and lactation alters expression of key miRNAs in the offspring. Results We studied the effects of maternal HF diet on the adult offspring by feeding mice with either a HF or a chow diet prior to conception, during pregnancy and lactation, and all offspring were weaned onto the same chow diet until adulthood. Maternal HF fed offspring had markedly increased hepatic mRNA levels of peroxisome proliferator activated receptor-alpha (ppar-alpha) and carnitine palmitoyl transferase-1a (cpt-1a) as well as insulin like growth factor-2 ( Igf2 ). A HF diet induced up-regulation of ppar-alpha and cpt-1a expression in the wild type but not in Igf2 knock out mice. Furthermore, hepatic expression of let-7c was also reduced in maternal HF fed offspring. Among 579 miRNAs measured with microarray, ~23 miRNA levels were reduced by ~1.5-4.9-fold. Reduced expression of miR-709 (a highly expressed miRNA), miR-122, miR-192, miR-194, miR-26a, let-7a, let7b and let-7c, miR-494 and miR-483* (reduced by ~4.9 fold) was validated by qPCR. We found that methyl-CpG binding protein 2 was the common predicted target for miR-709, miR-let7s, miR-122, miR-194 and miR-26a using our own purpose-built computer program. Conclusion Maternal HF feeding during pregnancy and lactation induced co-ordinated and long-lasting changes in expression of Igf2 , fat metabolic genes and several important miRNAs in the offspring.
The impact of a routine late third trimester growth scan on the incidence, diagnosis, and management of breech presentation in Oxfordshire, UK: A cohort study
Breech presentation at term contributes significantly to cesarean section (CS) rates worldwide. External cephalic version (ECV) is a safe procedure that reduces term breech presentation and associated CS. A principal barrier to ECV is failure to diagnose breech presentation. Failure to diagnose breech presentation also leads to emergency CS or unplanned vaginal breech birth. Recent evidence suggests that undiagnosed breech might be eliminated using a third trimester scan. Our aim was to evaluate the impact of introducing a routine 36-week scan on the incidence of breech presentation and of undiagnosed breech presentation. We carried out a population-based cohort study of pregnant women in a single unit covering Oxfordshire, United Kingdom. All women delivering between 37+0 and 42+6 weeks gestational age, with a singleton, nonanomalous fetus over a 4-year period (01 October 2014 to 30 September 2018) were included. The mean maternal age was 31 years, mean BMI 26, 44% were nulliparous, and 21% were of non-white ethnicity. Comparisons between the 2 years before and after introduction of routine 36-week scan were made for 2 primary outcomes of (1) the incidence of breech presentation and (2) undiagnosed breech presentation. Secondary outcomes related to ECV, mode of birth, and perinatal outcomes. Relative risks (RRs) with 95% confidence intervals (CIs) are reported. A total of 27,825 pregnancies were analysed (14,444 before and 13,381 after). A scan after 35+0 weeks was performed in 5,578 (38.6%) before, and 13,251 (99.0%) after (p < 0.001). The incidence of breech presentation at birth did not change significantly (2.6% and 2.7%) (RR 1.02; 95% CI 0.89, 1.18; p = 0.76). The rate of undiagnosed breech before labour reduced, from 22.3% to 4.7% (RR 0.21; 95% CI 0.12, 0.36; p < 0.001). Vaginal breech birth rates fell from 10.3% to 5.3% (RR 0.51; 95% CI 0.30, 0.87; p = 0.01); nonsignificant increases in elective CS rates and decreases in emergency CS rates for breech babies were seen. Neonatal outcomes were not significantly altered. Study limitations include insufficient numbers to detect serious adverse outcomes, that we cannot exclude secular changes over time which may have influenced our results, and that these findings are most applicable where a comprehensive ECV service exists. In this study, a universal 36-week scan policy was associated with a reduction in the incidence but not elimination of undiagnosed term breech presentation. There was no reduction in the incidence of breech presentation at birth, despite a comprehensive ECV service.