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A kagome lattice hosts a plethora of quantum states arising from the interplay between nontrivial topology and electron correlations. The recently discovered kagome magnet RMn6Sn6 (R represents a rare-earth element) is believed to showcase a kagome band closely resembling textbook characteristics. Here, we report the characterization of local electronic states and their magnetization response in YMn6Sn6 via scanning tunneling microscopy measurements under vector magnetic fields. Our spectroscopic maps reveal a spontaneously trimerized kagome electronic order in YMn6Sn6, where the 6-fold rotational symmetry is disrupted while translational symmetry is maintained. Further application of an external magnetic field demonstrates a strong coupling of the YMn6Sn6 kagome band to the field, which exhibits an energy shift discrepancy under different field directions, implying the existence of magnetization-response anisotropy and anomalous g factors. Our findings establish YMn6Sn6 as an ideal platform for investigating kagome-derived orbital magnetic moment and correlated magnetic topological states.
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ABSTRACTThe release of supersaturated total dissolved gas (STDG) from dams has been linked to the development of gas bubble disease, which can ultimately result in the death of fish. In order to minimize the impact of STDG on aquatic ecology, the effect of aeration on mass transfer at the air-liquid interface is taken into account. This paper selects four commonly used aerators to carry out indoor aeration tower experiments under different aeration conditions (aeration aperture, aeration water depth, and aeration volume), exploring aerators that can efficiently promote STDG release. The results indicated that the diaphragm aerator was found to have the greatest effect on STDG release, followed by corundum and spin mix aerator. In contrast, a pinhole aerator was found to have the least beneficial impact on STDG release. The increase in the release coefficient for the diaphragm aerator in comparison to the pinhole aerator is 32%. A prediction model for the aeration system was developed based on the mass transfer mechanism at the gas-liquid interface. The parameters in the model were determined using experimental data, which effectively improved the model's prediction accuracy. The findings of this study may serve as a reference point for the selection of the most suitable aerator in the actual engineering of STDG mitigation by aeration technology.
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Type 2 diabetes mellitus (T2DM) represents a common complication during pregnancy that affects fetoplacental development. We demonstrated the existence of impaired trophoblast syncytialization under hyperglycemic conditions. However, the exact mechanism remains unknown. RNA N6-methyladenosine (m6A) is an emerging regulatory mechanism of mRNA and participates in various biological processes. We described the global m6A modification pattern in T2DM placenta by the combined analysis of methylated RNA immunoprecipitation sequencing (MeRIP-Seq) and RNA sequencing (RNA-Seq). Both the m6A modification and expression of SIK1, which is critical for syncytialization, were significantly decreased in trophoblast exposed to hyperglycemic conditions. In addition, the m6A demethylase fat mass and obesity-associated protein (FTO) affects the expression and mRNA stability of SIK1 by binding to its 3'-untranslated region (UTR) m6A site. This work reveals that the FTO-m6A-SIK1 axis plays critical roles in regulating syncytialization in the placenta.
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Gestational diabetes mellitus (GDM) is characterized by insulin resistance and low-grade inflammation, and most studies have demonstrated gut dysbiosis in GDM pregnancies. Overall, they were manifested as a reduction in microbiome diversity and richness, depleted short chain fatty acid (SCFA)-producing genera and a dominant of Gram-negative pathogens releasing lipopolysaccharide (LPS). The SCFAs functioned as energy substance or signaling molecules to interact with host locally and beyond the gut. LPS contributed to pathophysiology of diseases through activating Toll-like receptor 4 (TLR4) and involved in inflammatory responses. The gut microbiome dysbiosis was not only closely related with GDM, it was also vital to fetal health through vertical transmission. In this review, we summarized gut microbiota signature in GDM pregnancies of each trimester, and presented a brief introduction of microbiome derived SCFAs. We then discussed mechanisms of microbiome-host interactions in the physiopathology of GDM and associated metabolic disorders. Finally, we compared offspring microbiota composition from GDM with that from normal pregnancies, and described the possible mechanism.
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Diabetes Gestacional , Disbiose , Ácidos Graxos Voláteis , Microbioma Gastrointestinal , Diabetes Gestacional/microbiologia , Diabetes Gestacional/metabolismo , Humanos , Gravidez , Feminino , Disbiose/microbiologia , Ácidos Graxos Voláteis/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Bactérias/isolamento & purificação , Interações entre Hospedeiro e Microrganismos , Lipopolissacarídeos/metabolismoRESUMO
Kagome lattice AV3Sb5 has attracted tremendous interest because it hosts correlated and topological physics. However, an in-depth understanding of the temperature-driven electronic states in AV3Sb5 is elusive. Here we use scanning tunneling microscopy to directly capture the rotational symmetry-breaking effect in KV3Sb5. Through both topography and spectroscopic imaging of defect-free KV3Sb5, we observe a charge density wave (CDW) phase transition from an a0 × a0 atomic lattice to a robust 2a0 × 2a0 superlattice upon cooling the sample to 60 K. An individual Sb-atom vacancy in KV3Sb5 further gives rise to the local Friedel oscillation (FO), visible as periodic charge modulations in spectroscopic maps. The rotational symmetry of the FO tends to break at the temperature lower than 40 K. Moreover, the FO intensity shows an obvious competition against the intensity of the CDW. Our results reveal a tantalizing electronic nematicity in KV3Sb5, highlighting the multiorbital correlation in the kagome lattice framework.
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In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.
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INTRODUCTION: Pre-eclampsia (PE) affects about 5% of Chinese pregnant women and is a major cause of maternal and perinatal morbidity and mortality. The first trimester screening model developed by the Fetal Medicine Foundation, which uses the Bayes theorem to combine maternal characteristics and medical history together with measurements of biomarkers, has been proven to be effective and has superior screening performance to that of the traditional risk factor-based approach for the prediction of PE. Prophylactic use of low-dose aspirin in women at risk for PE has resulted in a lower incidence of preterm-PE. However, there is no consensus on the preferred aspirin dosage for the prevention of preterm-PE. Evidence has also suggested that metformin has the potential benefit in preventing PE in pregnant women who are at high risk of the disorder. METHOD AND ANALYSIS: We present a protocol (V.2.0, date 17 March 2022) for the AVERT trial, which is a multicentre, double-blinded, 3-arm randomised controlled trial (RCT) that uses an effective PE screening programme to explore the optimal dosage of aspirin and the role of metformin for the prevention of PE among high-risk pregnant women in China. We intend to recruit 66 000 singleton pregnancies without treatment of low-dose aspirin and metformin at 11-13 weeks' gestation and all eligible women attending for their first trimester routine scan will be invited to undergo screening for preterm-PE by the combination of maternal factors, mean arterial pressure and placental growth factor. Women found to be at high risk of developing preterm-PE will be invited to take part in the RCT. This study will compare the incidence of preterm-PE with delivery at <37 weeks' gestation, as the primary outcome, of three different interventional groups: (1) aspirin 75 mg daily, (2) aspirin 150 mg daily and (3) aspirin 75 mg with metformin 1.5 g daily. 957 participants per treatment group are required to detect a significant difference of 59% in the reduction of the incidence of preterm-PE with 80% power and type I error of 5%. Pregnancy and neonatal outcomes will be collected and analysed. ETHICS AND DISSEMINATION: Ethical approval for the study was obtained from the Joint Chinese University of Hong Kong-New Territories East Cluster Clinical Research Ethics Committee (CREC Ref. No. 2021.406) in Hong Kong and the Ethics Committee of each participating hospital in Mainland China. The study is registered at ClinicalTrials.gov. The results of the AVERT trial will be disseminated at international academic conferences and published in high-impact factor journals. TRIAL REGISTRATION NUMBER: NCT05580523.
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Metformina , Pré-Eclâmpsia , Gravidez , Feminino , Recém-Nascido , Humanos , Aspirina , Pré-Eclâmpsia/epidemiologia , Método Duplo-Cego , China , Biomarcadores , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como AssuntoRESUMO
Quantum spin liquids (QSLs) are in a quantum disordered state that is highly entangled and has fractional excitations. As a highly sought-after state of matter, QSLs were predicted to host spinon excitations and to arise in frustrated spin systems with large quantum fluctuations. Here we report on the experimental observation and theoretical modeling of QSL signatures in monolayer 1T-NbSe2, which is a newly emerging two-dimensional material that exhibits both charge-density-wave (CDW) and correlated insulating behaviors. By using scanning tunneling microscopy and spectroscopy (STM/STS), we confirm the presence of spin fluctuations in monolayer 1T-NbSe2 by observing the Kondo resonance as monolayer 1T-NbSe2 interacts with metallic monolayer 1H-NbSe2. Subsequent STM/STS imaging of monolayer 1T-NbSe2 at the Hubbard band energy further reveals a long-wavelength charge modulation, in agreement with the spinon modulation expected for QSLs. By depositing manganese-phthalocyanine (MnPc) molecules with spin S = 3/2 onto monolayer 1T-NbSe2, new STS resonance peaks emerge at the Hubbard band edges of monolayer 1T-NbSe2. This observation is consistent with the spinon Kondo effect induced by a S = 3/2 magnetic impurity embedded in a QSL. Taken together, these experimental observations indicate that monolayer 1T-NbSe2 is a new promising QSL material.
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A Ni-catalyzed reductive dialkylation of 8-aminoquinoline-tethered aliphatic alkenes with two unactivated alkyl electrophiles is disclosed here. Key to the development of this transformation is the combination of primary alkyl (pseudo)halides and secondary alkyl iodides that produce products in a single regioselective manner. The reaction exhibits good functional group compatibility, and its synthetic utility was demonstrated by the concise synthesis of the precursors of biologically relevant molecules.
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BACKGROUND: Hyperglycemia during pregnancy can affect fetal heart in many ways, including causing cardiac malformation, leading to hypertrophic cardiomyopathy and cardiac dysfunction. Echocardiographic evaluation can assist identify alterations in heart structure, morphology and function, enabling prompt monitoring and management. However, according to earlier research, the cardiac alterations are modest in hyperglycemic mothers' fetuses, and might not be detectable using conventional methods and it is also unclear whether these changes are related to the metabolism of mothers. Fetal Heart Quantification (Fetal HQ) can assess ventricular geometry and function more sensitively and thoroughly, and identify sub-clinical cardiac dysfunction. The purpose of this study was to evaluate fetal heart by Fetal HQ in fetuses of hyperglycemic mothers who either had pre-gestational or gestational diabetes and to correlate them with maternal metabolic indices. METHODS: The fetuses of 25 gestational age-matched control mothers, 48 women with gestational diabetes mellitus (GDM), and 11 women with diabetes mellitus (DM) were included in the prospective case-control research. Using fetal echocardiography and speckle tracking echocardiography (STE), the heart of the fetus was evaluated. Differences in the groups' anthropometric, metabolic, and cardiac parameters were examined. It was assessed whether maternal features, prenatal glucose, lipids, and maternal hemoglobin A1c (HbA1c) correlated with fetal cardiac parameters. RESULTS: The LV EDV and ESV were significantly higher in the GDM group as compared to the DM group (p < 0.05). The GSI% was significantly lower in the GDM group compared with the control (p < 0.05). The LV SV and CO of the GDM group were both significantly higher compared with the DM group (p < 0.05). There was a significant decrease in RV FS for segments 1-7 in GDM fetuses compared to the control (p < 0.05) and for segments 5-10 compared to DM (p < 0.05). Fetal cardiac morphology and function indices correlate with maternal pregestational weight, BMI, early pregnancy fast glucose, lipids, and glycemic control levels. CONCLUSIONS: Fetuses exposed to gestational diabetes have altered heart morphology and function that is linked to maternal metabolic parameters, which presents a special indication for performing geometry and function cardiac assessment. Fetal HQ can be employed to evaluate the fetal cardiac shape and function in fetuses exposed to gestational diabetes.
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Diabetes Gestacional , Cardiopatias , Gravidez , Feminino , Humanos , Coração Fetal/diagnóstico por imagem , Glucose , Lipídeos , Ultrassonografia Pré-Natal/métodosRESUMO
OBJECTIVES: To systematically evaluate the efficacy of low molecular weight heparin (LMWH) to prevent preeclampsia in high risk pregnant women without thrombophilia. SEARCH STRATEGY: PubMed, Embase and the Cochrane library were searched for articles published before 1st August 2022 using the combination keywords "preeclampsia", "Low Molecular Weight Heparin", "LMWH", "Heparin, Low Molecular Weight", "Dalteparin", "Nadroparin", and "Tinzaparin". SELECTION CRITERIA: Randomized controlled trials evaluating the use of LMWH in pregnant women at high risk of preeclampsia without thrombophilia. DATA COLLECTION AND ANALYSIS: Ten studies were included in the meta-analysis (1758 patients in total). Outcomes were expressed as relative risk (RR) with 95% confidence intervals (CI). RESULTS: LMWH reduced the incidence of PE (RR = 0.67; 95% CI = 0.50-0.90; P = 0.009) in high risk pregnant women without thrombophilia. Subgroup analysis found that the prophylactic effect of LMWH was only significant in studies using low-dose aspirin (LDA) as the primary intervention. The combination of LMWH and LDA was also effective for the prevention of preterm birth and fetal growth restriction, but had no effect on the incidence of placenta abruption. CONCLUSION: For women at high risk of developing preeclampsia without thrombophilia, the combination of LMWH and low-dose aspirin is effective for the prevention of preeclampsia, preterm birth and fetal growth restriction and is superior to LDA alone.
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Pré-Eclâmpsia , Nascimento Prematuro , Trombofilia , Feminino , Recém-Nascido , Humanos , Gravidez , Heparina de Baixo Peso Molecular/uso terapêutico , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/prevenção & controle , Pré-Eclâmpsia/tratamento farmacológico , Gravidez de Alto Risco , Nascimento Prematuro/tratamento farmacológico , Retardo do Crescimento Fetal/tratamento farmacológico , Aspirina/uso terapêutico , Heparina/uso terapêutico , Nadroparina , Trombofilia/complicações , Trombofilia/tratamento farmacológico , Anticoagulantes/uso terapêuticoRESUMO
BACKGROUND: Alterations in the placental expression of glucose transporters (GLUTs), the crucial maternal-fetal nutrient transporters, have been found in women with hyperglycemia in pregnancy (HIP). However, there is still uncertainty about the underlying effect of the high-glucose environment on placental GLUTs expression in HIP. METHODS: We quantitatively evaluated the activity of mammalian target of rapamycin (mTOR) and expression of GLUTs (GLUT1, GLUT3, and GLUT4) in the placenta of women with normal pregnancies (CTRL, n = 12) and pregnant women complicated with poorly controlled type 2 diabetes mellitus (T2DM, n = 12) by immunohistochemistry. In addition, BeWo cells were treated with different glucose concentrations to verify the regulation of hyperglycemia. Then, changes in the expression of GLUTs following the activation or suppression of the mTOR pathway were also assessed using MHY1485/rapamycin (RAPA) treatment or small interfering RNA (siRNA)-mediated silencing approaches. Moreover, we further explored the alteration and potential upstream regulatory role of methyltransferase-like 3 (METTL3) when exposed to hyperglycemia. RESULTS: mTOR, phosphorylated mTOR (p-mTOR), and GLUT1 protein levels were upregulated in the placenta of women with T2DM compared with those CTRL. In BeWo cells, mTOR activity increased with increasing glucose concentration, and the expression of GLUT1, GLUT3, and GLUT4 as well as GLUT1 cell membrane translocation were upregulated by hyperglycemia to varying degrees. Both the drug-mediated and genetic depletion of mTOR signaling in BeWo cells suppressed GLUTs expression, whereas MHY1485-induced mTOR activation upregulated GLUTs expression. Additionally, high glucose levels upregulated METTL3 expression and nuclear translocation, and decreasing METTL3 levels suppressed GLUTs expression and mTOR activity and vice versa. Furthermore, in METTL3 knockdown BeWo cells, the inhibitory effect on GLUTs expression was eliminated by activating the mTOR signaling pathway using MHY1485. CONCLUSION: High-glucose environment-induced upregulation of METTL3 in trophoblasts regulates the expression of GLUTs through mTOR signaling, contributing to disordered nutrient transport in women with HIP.
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Supersaturated total dissolved gas (TDG) generation in rivers poses great harm to aquatic organisms. In this paper, 30 groups of supersaturated TDG dissipation experiments with aeration were carried out. These results showed that aeration actively promoted the dissipation of supersaturated TDG. The aeration rate decreased by 34.94% from 1.0 m3/h to 5.0 m3/h, the reduced proportion of aeration aperture was 35.51% from 215 mm to 260 mm, whereas the aeration depth increased by 16.93% from 0.4 m to 1.2 m for the TDG dissipation time required, resulting in corresponding the variation of TDG dissipation coefficients were 86.26%, 23.74% and -5.39%, respectively. In general, the effect on TDG dissipation is that the aeration rate is the largest, followed by the aeration aperture, and the aeration depth is the smallest. A quantitative relationship was established between TDG dissipation coefficient and aeration conditions, and followed a power function, while the aeration depth inhibited its dissipation. Moreover, what matters was that a numerical model was presented for predicting the TDG dissipation in Eulerian-Eulerian. When the parameter was ß = 10.52, the error between the original experimental data and the simulated of a multiphase TDG dissipation model was 0.2%. The study provides essential scientific data for mitigating the harms of supersaturated TDG.
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Gases , Movimentos da Água , RiosRESUMO
1D grain boundaries in transition metal dichalcogenides (TMDs) are ideal for investigating the collective electron behavior in confined systems. However, clear identification of atomic structures at the grain boundaries, as well as precise characterization of the electronic ground states, have largely been elusive. Here, direct evidence for the confined electronic states and the charge density modulations at mirror twin boundaries (MTBs) of monolayer NbSe2 , a representative charge-density-wave (CDW) metal, is provided. The scanning tunneling microscopy (STM) measurements, accompanied by the first-principles calculations, reveal that there are two types of MTBs in monolayer NbSe2 , both of which exhibit band bending effect and 1D boundary states. Moreover, the intrinsic CDW signatures of monolayer NbSe2 are dramatically suppressed as approaching an isolated MTB but can be either enhanced or suppressed in the MTB-constituted confined wedges. Such a phenomenon can be well explained by the MTB-CDW interference interactions. The results reveal the underlying physics of the confined electrons at MTBs of CDW metals, paving the way for the grain boundary engineering of the functionality.
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OBJECTIVE: This study was to evaluate plasma galectin-3 levels from early pregnancy to delivery and explore the effects of galectin-3 on the function of trophoblast cells under high glucose exposure. METHODS: The plasma galectin-3 levels were quantified by enzyme-linked immunosorbent assay (ELISA) in the China National Birth Cohort (CNBC) at Peking University First Hospital, and the underlying signaling pathway was identified by protein-protein interaction (PPI) analysis, gene set enrichment analysis (GSEA), quantitative PCR (qPCR), western blotting, small interfering RNA (siRNA) transfections, and flow cytometry. RESULTS: Significantly higher galectin-3 levels were found in patients with gestational diabetes mellitus (GDM group; n = 77) during the first and second trimesters than that in healthy pregnant women (HP group; n = 113) (P < 0.05). No significant differences in plasma galectin-3 levels were detected between GDM and HP groups in maternal third-trimester blood and cord blood. PPI analysis suggested potential interactions between galectin-3 and foxc1. The findings of GSEA showed that galectin-3 was involved in the cytochrome P450-related and complement-related pathways, and foxc1 was associated with type I diabetes mellitus. Additionally, high glucose (25 mM) significantly increased the expression levels of galectin-3 and foxc1 and induced apoptosis in HTR-8/SVneo cells. Further in vitro experiments showed that galectin-3/foxc1 pathway could protect HTR-8/SVneo cells against high glucose - induced apoptosis. CONCLUSION: Future studies were required to validate whether plasma galectin-3 might become a potential biomarker for hyperglycemia during pregnancy. Elevated galectin-3 levels might be a vital protective mechanism among those exposed to hyperglycemia during pregnancy.
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Galectina 3 , Hiperglicemia , Feminino , Humanos , Gravidez , Apoptose , Galectina 3/genética , Glucose , TrofoblastosRESUMO
BACKGROUND: Birthweight is the most common and accessible parameter in assessing neonatal perinatal outcomes and in evaluating the intrauterine environment globally. Infants born too large or too small not only may alter the maternal mode of delivery but also may face other long-term disorders, such as metabolic diseases and neurodevelopmental delay. Studies have revealed different growth profiles of large-for-gestational-age and small-for-gestational-age fetuses in singleton pregnancies. However, currently, no research is focused on the growth trajectories of these infants during twin pregnancies, even though they are at a much higher risk of being small for gestational age. OBJECTIVE: This study aimed to explore fetal growth trajectories of large-for-gestational-age and small-for-gestational-age infants in twin pregnancies to provide strategies for fetal growth management. STUDY DESIGN: This was a case-control study of all noncomplicated twin pregnancies delivered after 36 weeks of gestation at the Peking University First Hospital between 2012 and 2021. Ultrasound data were recorded every 2 to 4 weeks until delivery. All the infants were divided into large-for-gestational-age, small-for-gestational-age, and appropriate-for-gestational-age groups. Longitudinal fetal growth (estimated fetal weight, abdominal circumference, etc.) was compared among the 3 groups using a linear mixed model, and other maternal and neonatal perinatal outcomes were compared. Receiver operating characteristic curves were used to explore optimal biometric parameters and gestational weeks for predicting small-for-gestational-age infants. RESULTS: Here, 797 pregnant patients with 1494 infants were recruited, with 59 small-for-gestational-age infants, 1335 appropriate-for-gestational-age infants, and 200 large-for-gestational-age infants. The mean birthweights were 1985.34±28.34 g in small-for-gestational-age infants, 2662.08±6.60 g in appropriate-for-gestational-age infants, and 3231.24±11.04 g in large-for-gestational-age infants. The estimated fetal weight of the 3 groups differed from each other from week 26, with the small-for-gestational-age fetuses weighing 51.946 g less and the large-for-gestational-age fetuses weighing 35.233 g more than the appropriate-for-gestational-age fetuses. This difference increased with gestation; at 39 weeks, the small-for-gestational-age fetuses weighed 707.438 g less and the large-for-gestational-age fetuses weighed 614.182 g more than the appropriate-for-gestational-age fetuses (all P<.05). The small-for-gestational-age group had a significantly higher rate of hospitalization (89.9 %) and jaundice (40.7 %) than the appropriate-for-gestational-age group, whereas the hospitalization rate in the large-for-gestational-age group was significantly lower than the appropriate-for-gestational-age group (7.5% and 2.5%; all P<.05). The fetal weight of the small-for-gestational-age infants with adverse outcomes remained near the 10th percentile of the reference and fell below the 3rd percentile at 34 weeks of gestation. The estimated fetal weight after 30 weeks of gestation had a satisfactory diagnostic value in predicting small-for-gestational-age infants. At 30, 32, 34, and 36 weeks of gestation, the areas under the curve were 0.829, 0.840, 0.929, and 0.889 respectively. CONCLUSION: The growth patterns of small-for-gestational-age, appropriate-for-gestational-age, and large-for-gestational-age twin fetuses diverged from 26 weeks of gestation and continued to increase until delivery; therefore, closer monitoring is suggested from 26 weeks of gestation for those carrying small fetuses.
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Retardo do Crescimento Fetal , Peso Fetal , Recém-Nascido Grande para a Idade Gestacional , Gravidez de Gêmeos , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Peso ao Nascer , Estudos de Casos e Controles , Desenvolvimento Fetal , Retardo do Crescimento Fetal/diagnóstico , Retardo do Crescimento Fetal/epidemiologia , Idade Gestacional , Ultrassonografia Pré-NatalRESUMO
BACKGROUND: N6-methyladenosine (m6A) is one of the predominant RNA epigenetic modifications that modify RNAs reversibly and dynamically by "writers" (methyltransferase), "erasers" (demethylase), and "readers." OBJECTIVE: This review aimed to provide a comprehensive understanding of the complexity of m6A regulation in the great obstetrical syndromes to understand its pathogenesis and potential therapeutic targets. METHODS: The terms "placenta or trophoblast" and "m6A or N6-methyladenosine" were searched in PubMed databases (June 2023). RESULTS: In this review, we discuss the regulatory role of m6A in the great obstetrical syndromes such as preeclampsia (PE), spontaneous abortion (SA), hyperglycemia in pregnancy (HIP) and fetal growth to emphasize the clinical relevance of m6A dysregulation in pregnancy. We also describe mechanisms that potentially involve the participation of m6A methylation, such as proliferation, invasion, migration, apoptosis, autophagy, endoplasmic reticulum stress, macrophage polarization, and inflammation. CONCLUSION: We summarize the recent research progress on the role of m6A modification in the great obstetrical syndromes and placental function and provide a brief perspective on its prospective applications.
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Aborto Espontâneo , Placenta , Gravidez , Humanos , Feminino , Síndrome , Adenosina , ApoptoseRESUMO
The establishment of human gut microbiota in early life is closely associated with both short- and long-term infant health. Delivery mode and feeding pattern are two important determinants of infant gut microbiota. In this longitudinal cohort study, we examined the interplay between the delivery mode and feeding pattern on the dynamics of infant gut microbiota from 6 weeks to 6 months post-delivery in 139 infants. We also assessed the relationship between infant respiratory infection susceptibility and gut microbial changes associated with delivery mode and feeding pattern. At 6 weeks postpartum, the composition and structure of gut microbiota of cesarean section-delivered (CSD) infants differed from those of vaginally delivered (VD) infants, with decreased Bacteroides and Escherichia-Shigella and increased Klebsiella, Veillonella, and Enterococcus. At 6 months postpartum, these delivery mode-induced microbial shifts were restored by exclusive breastfeeding, resulting in similar gut microbial profiles between VD and CSD infants who were exclusively breastfed (P = 0.57) and more variable gut microbial profiles between VD and CSD infants who were mixed fed (P < 0.001). We identified that the VD-associated genera were enriched in healthy infants, while the CSD-associated genera were enriched in infants who suffered from respiratory infections. Our findings indicate that exclusive breastfeeding may play a health-promoting role by reducing infant respiratory infection susceptibility through the restoration of gut microbiota perturbations caused by cesarean section.