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1.
Cell ; 161(4): 858-67, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25957689

RESUMO

The mitochondrion maintains and regulates its proteome with chaperones primarily inherited from its bacterial endosymbiont ancestor. Among these chaperones is the AAA+ unfoldase ClpX, an important regulator of prokaryotic physiology with poorly defined function in the eukaryotic mitochondrion. We observed phenotypic similarity in S. cerevisiae genetic interaction data between mitochondrial ClpX (mtClpX) and genes contributing to heme biosynthesis, an essential mitochondrial function. Metabolomic analysis revealed that 5-aminolevulinic acid (ALA), the first heme precursor, is 5-fold reduced in yeast lacking mtClpX activity and that total heme is reduced by half. mtClpX directly stimulates ALA synthase in vitro by catalyzing incorporation of its cofactor, pyridoxal phosphate. This activity is conserved in mammalian homologs; additionally, mtClpX depletion impairs vertebrate erythropoiesis, which requires massive upregulation of heme biosynthesis to supply hemoglobin. mtClpX, therefore, is a widely conserved stimulator of an essential biosynthetic pathway and uses a previously unrecognized mechanism for AAA+ unfoldases.


Assuntos
Endopeptidase Clp/metabolismo , Eritropoese , Eucariotos/metabolismo , Heme/biossíntese , 5-Aminolevulinato Sintetase/metabolismo , Sequência de Aminoácidos , Ácido Aminolevulínico/metabolismo , Animais , Evolução Biológica , Endopeptidase Clp/química , Endopeptidase Clp/genética , Eucariotos/genética , Humanos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Chaperonas Moleculares/metabolismo , Dados de Sequência Molecular , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Alinhamento de Sequência , Peixe-Zebra/metabolismo
2.
Nature ; 625(7993): 175-180, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38093006

RESUMO

Oxytocin (OXT), a nine-amino-acid peptide produced in the hypothalamus and released by the posterior pituitary, has well-known actions in parturition, lactation and social behaviour1, and has become an intriguing therapeutic target for conditions such as autism and schizophrenia2. Exogenous OXT has also been shown to have effects on body weight, lipid levels and glucose homeostasis1,3, suggesting that it may also have therapeutic potential for metabolic disease1,4. It is unclear, however, whether endogenous OXT participates in metabolic homeostasis. Here we show that OXT is a critical regulator of adipose tissue lipolysis in both mice and humans. In addition, OXT serves to facilitate the ability of ß-adrenergic agonists to fully promote lipolysis. Most surprisingly, the relevant source of OXT in these metabolic actions is a previously unidentified subpopulation of tyrosine hydroxylase-positive sympathetic neurons. Our data reveal that OXT from the peripheral nervous system is an endogenous regulator of adipose and systemic metabolism.


Assuntos
Tecido Adiposo , Lipólise , Neurônios , Ocitocina , Animais , Humanos , Camundongos , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Agonistas Adrenérgicos beta/farmacologia , Lipólise/efeitos dos fármacos , Neurônios/metabolismo , Ocitocina/metabolismo , Ocitocina/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
3.
Nature ; 613(7945): 639-649, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36697862

RESUMO

Whether the human fetus and the prenatal intrauterine environment (amniotic fluid and placenta) are stably colonized by microbial communities in a healthy pregnancy remains a subject of debate. Here we evaluate recent studies that characterized microbial populations in human fetuses from the perspectives of reproductive biology, microbial ecology, bioinformatics, immunology, clinical microbiology and gnotobiology, and assess possible mechanisms by which the fetus might interact with microorganisms. Our analysis indicates that the detected microbial signals are likely the result of contamination during the clinical procedures to obtain fetal samples or during DNA extraction and DNA sequencing. Furthermore, the existence of live and replicating microbial populations in healthy fetal tissues is not compatible with fundamental concepts of immunology, clinical microbiology and the derivation of germ-free mammals. These conclusions are important to our understanding of human immune development and illustrate common pitfalls in the microbial analyses of many other low-biomass environments. The pursuit of a fetal microbiome serves as a cautionary example of the challenges of sequence-based microbiome studies when biomass is low or absent, and emphasizes the need for a trans-disciplinary approach that goes beyond contamination controls by also incorporating biological, ecological and mechanistic concepts.


Assuntos
Biomassa , Contaminação por DNA , Feto , Microbiota , Animais , Feminino , Humanos , Gravidez , Líquido Amniótico/imunologia , Líquido Amniótico/microbiologia , Mamíferos , Microbiota/genética , Placenta/imunologia , Placenta/microbiologia , Feto/imunologia , Feto/microbiologia , Reprodutibilidade dos Testes
4.
Nat Methods ; 21(1): 132-141, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38129618

RESUMO

Multiphoton microscopy can resolve fluorescent structures and dynamics deep in scattering tissue and has transformed neural imaging, but applying this technique in vivo can be limited by the mechanical and optical constraints of conventional objectives. Short working distance objectives can collide with compact surgical windows or other instrumentation and preclude imaging. Here we present an ultra-long working distance (20 mm) air objective called the Cousa objective. It is optimized for performance across multiphoton imaging wavelengths, offers a more than 4 mm2 field of view with submicrometer lateral resolution and is compatible with commonly used multiphoton imaging systems. A novel mechanical design, wider than typical microscope objectives, enabled this combination of specifications. We share the full optical prescription, and report performance including in vivo two-photon and three-photon imaging in an array of species and preparations, including nonhuman primates. The Cousa objective can enable a range of experiments in neuroscience and beyond.


Assuntos
Corantes , Microscopia de Fluorescência por Excitação Multifotônica , Animais , Microscopia de Fluorescência por Excitação Multifotônica/métodos
5.
Nature ; 592(7852): 80-85, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33692543

RESUMO

Placentas can exhibit chromosomal aberrations that are absent from the fetus1. The basis of this genetic segregation, which is known as confined placental mosaicism, remains unknown. Here we investigated the phylogeny of human placental cells as reconstructed from somatic mutations, using whole-genome sequencing of 86 bulk placental samples (with a median weight of 28 mg) and of 106 microdissections of placental tissue. We found that every bulk placental sample represents a clonal expansion that is genetically distinct, and exhibits a genomic landscape akin to that of childhood cancer in terms of mutation burden and mutational imprints. To our knowledge, unlike any other healthy human tissue studied so far, the placental genomes often contained changes in copy number. We reconstructed phylogenetic relationships between tissues from the same pregnancy, which revealed that developmental bottlenecks genetically isolate placental tissues by separating trophectodermal lineages from lineages derived from the inner cell mass. Notably, there were some cases with full segregation-within a few cell divisions of the zygote-of placental lineages and lineages derived from the inner cell mass. Such early embryonic bottlenecks may enable the normalization of zygotic aneuploidy. We observed direct evidence for this in a case of mosaic trisomic rescue. Our findings reveal extensive mutagenesis in placental tissues and suggest that mosaicism is a typical feature of placental development.


Assuntos
Mosaicismo , Mutagênese , Mutação , Placenta/metabolismo , Biópsia , Massa Celular Interna do Blastocisto/citologia , Feminino , Genoma Humano/genética , Humanos , Mesoderma/citologia , Taxa de Mutação , Placenta/citologia , Gravidez , Trissomia/genética , Trofoblastos/citologia , Trofoblastos/metabolismo , Zigoto/citologia
6.
Proc Natl Acad Sci U S A ; 121(11): e2313743121, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38446851

RESUMO

In order to deal with a complex environment, animals form a diverse range of neural representations that vary across cortical areas, ranging from largely unimodal sensory input to higher-order representations of goals, outcomes, and motivation. The developmental origin of this diversity is currently unclear, as representations could arise through processes that are already area-specific from the earliest developmental stages or alternatively, they could emerge from an initially common functional organization shared across areas. Here, we use spontaneous activity recorded with two-photon and widefield calcium imaging to reveal the functional organization across the early developing cortex in ferrets, a species with a well-characterized columnar organization and modular structure of spontaneous activity in the visual cortex. We find that in animals 7 to 14 d prior to eye-opening and ear canal opening, spontaneous activity in both sensory areas (auditory and somatosensory cortex, A1 and S1, respectively), and association areas (posterior parietal and prefrontal cortex, PPC and PFC, respectively) showed an organized and modular structure that is highly similar to the organization in V1. In all cortical areas, this modular activity was distributed across the cortical surface, forming functional networks that exhibit millimeter-scale correlations. Moreover, this modular structure was evident in highly coherent spontaneous activity at the cellular level, with strong correlations among local populations of neurons apparent in all cortical areas examined. Together, our results demonstrate a common distributed and modular organization across the cortex during early development, suggesting that diverse cortical representations develop initially according to similar design principles.


Assuntos
Cálcio da Dieta , Furões , Animais , Motivação , Neurônios , Fótons
7.
Nature ; 572(7769): 329-334, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31367035

RESUMO

We sought to determine whether pre-eclampsia, spontaneous preterm birth or the delivery of infants who are small for gestational age were associated with the presence of bacterial DNA in the human placenta. Here we show that there was no evidence for the presence of bacteria in the large majority of placental samples, from both complicated and uncomplicated pregnancies. Almost all signals were related either to the acquisition of bacteria during labour and delivery, or to contamination of laboratory reagents with bacterial DNA. The exception was Streptococcus agalactiae (group B Streptococcus), for which non-contaminant signals were detected in approximately 5% of samples collected before the onset of labour. We conclude that bacterial infection of the placenta is not a common cause of adverse pregnancy outcome and that the human placenta does not have a microbiome, but it does represent a potential site of perinatal acquisition of S. agalactiae, a major cause of neonatal sepsis.


Assuntos
Parto Obstétrico , Complicações do Trabalho de Parto/microbiologia , Placenta/microbiologia , Complicações Infecciosas na Gravidez/microbiologia , Sepse/congênito , Sepse/microbiologia , Streptococcus agalactiae/isolamento & purificação , Streptococcus agalactiae/patogenicidade , Biópsia , Estudos de Coortes , Contaminação por DNA , DNA Bacteriano/análise , DNA Bacteriano/genética , DNA Bacteriano/isolamento & purificação , Feminino , Humanos , Recém-Nascido , Masculino , Metagenômica , Gravidez , Resultado da Gravidez , RNA Ribossômico 16S/análise , RNA Ribossômico 16S/genética , Reprodutibilidade dos Testes , Análise de Sequência de DNA
8.
Nature ; 574(7778): E15, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31570886

RESUMO

An Amendment to this paper has been published and can be accessed via a link at the top of the paper.

9.
Mol Ecol ; 33(7): e17306, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38414303

RESUMO

Variation in how individuals interact with food resources can directly impact, and be affected by, their microbial interactions due to the potential for transmission. The degree to which this transmission occurs, however, may depend on the structure of forager networks, which determine the community-scale transmission opportunities. In particular, how the community-scale opportunity for transfer balances individual-scale barriers to transmission is unclear. Examining the bee-flower and bee-microbial interactions of over 1000 individual bees, we tested (1) the degree to which individual floral visits predicted microbiome composition and (2) whether plant-bee networks with increased opportunity for microbial transmission homogenized the microbiomes of bees within that network. The pollen community composition carried by bees was associated with microbiome composition at some sites, suggesting that microbial transmission at flowers occurred. Contrary to our predictions, however, microbiome variability did not differ based on transfer opportunity: bee microbiomes in asymmetric networks with high opportunity for microbial transfer were similarly variable compared to microbiomes in networks with more evenly distributed links. These findings suggest that microbial transmission at flowers is frequent enough to be observed at the community level, but that community network structure did not substantially change the dynamics of this transmission, perhaps due to filtering processes in host guts.


Assuntos
Microbioma Gastrointestinal , Plantas , Humanos , Abelhas/genética , Animais , Pólen/genética , Flores , Polinização
10.
Am J Public Health ; 114(10): 1086-1096, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39231413

RESUMO

Objectives. To analyze War on Drugs encounters and their relationships to health care utilization among White people who use drugs (PWUD) in 22 Appalachian rural counties in Kentucky, West Virginia, Ohio, and North Carolina. Methods. We recruited White PWUD using chain referral sampling in 2018 to 2020. Surveys asked about criminal-legal encounters, unmet health care needs, and other covariates. We used generalized estimating equations to regress unmet need on criminal-legal encounters in multivariable models. Results. In this sample (n = 957), rates of stop and search, arrest, incarceration, and community supervision were high (44.0%, 26.8%, 36.3%, and 31.1%, respectively), as was unmet need (68.5%). Criminal-legal encounters were unrelated to unmet need (stops: adjusted prevalence ratio [APR] = 1.13; 95% confidence interval [CI] = 0.97, 1.32; arrest: APR = 0.95; 95% CI = 0.78, 1.15; incarceration: APR = 1.01; 95% CI = 0.89, 1.14; community supervision: APR = 0.99; 95% CI = 0.90, 1.09). Conclusions. Contrasting with findings from predominantly Black urban areas, criminal-legal encounters and unmet need were unrelated among White Appalachian PWUD. Research should explore whether and under what conditions White supremacy's benefits might buffer adverse impacts of the War on Drugs in Appalachia. (Am J Public Health. 2024;114(10):1086-1096. https://doi.org/10.2105/AJPH.2024.307744).


Assuntos
Aceitação pelo Paciente de Cuidados de Saúde , População Rural , Transtornos Relacionados ao Uso de Substâncias , População Branca , Humanos , Masculino , Feminino , Adulto , Região dos Apalaches , População Rural/estatística & dados numéricos , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Substâncias/epidemiologia , População Branca/estatística & dados numéricos , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Racismo/estatística & dados numéricos , Usuários de Drogas/estatística & dados numéricos
11.
BJOG ; 131(6): 823-831, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37822261

RESUMO

OBJECTIVE: To determine the inter-relationships between five first-trimester biomarkers (pregnancy associated plasma protein A [PAPP-A], alpha-fetoprotein [AFP], beta human chorionic gonadotrophin [beta-hCG], placenta growth factor [PlGF] and soluble fms-like tyrosine kinase receptor-1 [sFlt-1]) and a range of adverse pregnancy outcomes (APOs). DESIGN: Prospective cohort study of nulliparous singleton pregnancy. SETTING: Cambridge, UK. POPULATION OR SAMPLE: 4056 pregnancy outcome prediction study participants. METHODS: The biomarker concentrations were measured in maternal serum at ~12 weeks of gestation. Univariable analysis of APOs was performed using logistic regression. Multivariable analysis used best subsets logistic regression with cross-validation. MAIN OUTCOME MEASURES: Pre-eclampsia (PE), small for gestational age (SGA), including severe SGA (birthweight <3rd), fetal growth restriction (FGR), preterm birth (PTB, both induced and spontaneous [iPTB and sPTB, respectively]), pre-viable loss and stillbirth, plus combinations of outcomes. RESULTS: Lower values of PAPP-A, PlGF and sFlt-1 and higher values of AFP were associated with FGR (OR for 1 SD higher value 0.59 [95% CI 0.48-0.74], OR 0.56 [95% CI 0.44-0.70], OR 0.68 [95% CI 0.54-0.87] and OR 1.53 [95% CI 1.25-1.88]), severe SGA (OR 0.59 [95% CI 0.49-0.72], OR 0.71 [95% CI 0.57-0.87], OR 0.74 [95% CI 0.60-0.91] and OR 1.41 [95% CI 1.17-1.71]), sPTB (OR 0.61 [95% CI 0.50-0.73], OR 0.79 [95% CI 0.66-0.96], OR 0.57 [95% CI 0.47-0.70] and OR 1.41 [95% CI 1.18-1.67]) and iPTB (OR 0.72 [95% CI 0.57-0.91], OR 0.62 [95% CI 0.49-0.78], OR 0.71 [95% CI 0.56-0.90] and OR 1.44 [95% CI 1.16-1.78]), respectively. When combinations of biomarkers were assessed, PAPP-A and AFP were independently associated with severe SGA; PAPP-A alone with PE + PTB; PlGF alone with severe PE; PlGF, beta-hCG, AFP and PAPP-A with the combination of PE and SGA; AFP and sFlt-1 with sPTB; and AFP and PlGF with iPTB. CONCLUSIONS: Combinations of first-trimester placental biomarkers are associated with APOs. However, the patterns vary for different types of APO, indicating heterogeneity in the underlying pathophysiological pathways.


Assuntos
Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Recém-Nascido , Feminino , Humanos , Resultado da Gravidez , Primeiro Trimestre da Gravidez , alfa-Fetoproteínas , Proteína Plasmática A Associada à Gravidez , Estudos Prospectivos , Placenta/metabolismo , Fator de Crescimento Placentário , Gonadotropina Coriônica Humana Subunidade beta , Biomarcadores , Retardo do Crescimento Fetal/diagnóstico , Pré-Eclâmpsia/diagnóstico , Receptor 1 de Fatores de Crescimento do Endotélio Vascular
12.
BJOG ; 2024 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-39256942

RESUMO

BACKGROUND: Globally, caesarean births (CB), including emergency caesareans births (EmCB), are rising. It is estimated that nearly a third of all births will be CB by 2030. OBJECTIVES: Identify and summarise the results from studies developing and validating prognostic multivariable models predicting the risk of EmCBs. Ultimately understanding the accuracy of their development, and whether they are operationalised for use in routine clinical practice. SEARCH STRATEGY: Studies were identified using databases: MEDLINE, CINAHL, Cochrane Central and Scopus with a search strategy tailored to models predicting EmCBs. SELECTION CRITERIA: Prospective studies developing and validating clinical prediction models, with two or more covariates, to predict risk of EmCB. DATA COLLECTION AND ANALYSIS: Data were extracted onto a proforma using the Prediction model Risk Of Bias ASsessment Tool (PROBAST). RESULTS: In total, 8083 studies resulted in 56 unique prediction modelling studies and seven validating studies, with a total of 121 different predictors. Frequently occurring predictors included maternal height, maternal age, parity, BMI and gestational age. PROBAST highlighted 33 studies with low overall bias, and these all internally validated their model. Thirteen studies externally validated; only eight of these were graded an overall low risk of bias. Six models offered applications that could be readily used, but only one provided enough time to offer a planned caesarean birth (pCB). These well-refined models have not been recalibrated since development. Only one model, developed in a relatively low-risk population, with data collected a decade ago, remains useful at 36 weeks for arranging a pCB. CONCLUSION: To improve personalised clinical conversations, there is a pressing need for a model that accurately predicts the timely risk of an EmCB for women across diverse clinical backgrounds. TRIAL REGISTRATION: PROSPERO registration number: CRD42023384439.

13.
Harm Reduct J ; 21(1): 154, 2024 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-39182116

RESUMO

AIM: Illicitly manufactured fentanyl and its analogs are the primary drivers of opioid overdose deaths in the United States (U.S.). People who use drugs may be exposed to fentanyl or its analogs intentionally or unintentionally. This study sought to identify strategies used by rural people who use drugs to reduce harms associated with unintentional fentanyl exposure. METHODS: This analysis focused on 349 semi-structured qualitative interviews across 10 states and 58 rural counties in the U.S conducted between 2018 and 2020. Interview guides were collaboratively standardized across sites and included questions about drug use history (including drugs currently used, frequency of use, mode of administration) and questions specific to fentanyl. Deductive coding was used to code all data, then inductive coding of overdose and fentanyl codes was conducted by an interdisciplinary writing team. RESULTS: Participants described being concerned that fentanyl had saturated the drug market, in both stimulant and opioid supplies. Participants utilized strategies including: (1) avoiding drugs that were perceived to contain fentanyl, (2) buying drugs from trusted sources, (3) using fentanyl test strips, 4) using small doses and non-injection routes, (5) using with other people, (6) tasting, smelling, and looking at drugs before use, and (7) carrying and using naloxone. Most people who used drugs used a combination of these strategies as there was an overwhelming fear of fatal overdose. CONCLUSION: People who use drugs living in rural areas of the U.S. are aware that fentanyl is in their drug supply and use several strategies to prevent associated harms, including fatal overdose. Increasing access to harm reduction tools (e.g., fentanyl test strips, naloxone) and services (e.g., community drug checking, syringe services programs, overdose prevention centers) should be prioritized to address the polysubstance-involved overdose crisis. These efforts should target persons who use opioids and other drugs that may contain fentanyl.


Assuntos
Analgésicos Opioides , Fentanila , Redução do Dano , População Rural , Humanos , Fentanila/intoxicação , Feminino , Estados Unidos/epidemiologia , Adulto , Masculino , Analgésicos Opioides/intoxicação , Analgésicos Opioides/efeitos adversos , Pessoa de Meia-Idade , Transtornos Relacionados ao Uso de Opioides/prevenção & controle , Overdose de Drogas/prevenção & controle , Overdose de Drogas/epidemiologia , Overdose de Opiáceos/prevenção & controle , Overdose de Opiáceos/epidemiologia , Adulto Jovem , Pesquisa Qualitativa , Naloxona/uso terapêutico
14.
Artigo em Inglês | MEDLINE | ID: mdl-39237824

RESUMO

Selective serotonin reuptake inhibitors (SSRIs) including citalopram are commonly used antidepressants that can be involved in drug-related deaths along with opioids and other substances. This study characterized citalopram involvement in West Virginia (WV) drug-related deaths compared to other SSRI and non-SSRI-related deaths. All 2005-2021 WV drug-related deaths were analyzed in this retrospective study. Demographics, other substances involved, and comorbidities in cases in which citalopram was listed on the death certificate were compared to other SSRI-related and total non-SSRI deaths. Citalopram concentrations and the association between citalopram presence with predicted fentanyl concentrations were determined. Citalopram was the most common antidepressant present in the deaths (4.5% of 14,363 total), with most (81%) unintentional. Male: female ratios in citalopram cases (0.9:1) were significantly lower than in non-SSRI deaths (2.3:1). Almost two-thirds of citalopram deaths had ≥ 4 substances involved compared to 26% of non-SSRI deaths. Overall, oxycodone was most frequently identified in citalopram deaths (fentanyl more commonly in recent years), followed by alprazolam and diazepam. Cardiovascular comorbidity was significantly more common in citalopram than non-SSRI deaths. No association was found between citalopram presence and predicted fentanyl concentrations. Most citalopram-related deaths were unintentional and involved proportionately more females, with larger numbers of concurrent substances present and more cardiovascular comorbidity compared to non-SSRI deaths. Citalopram is widely used and less toxic than many antidepressants. The extent to which it contributed to overdose deaths can be difficult to ascertain given the multiple substances usually present.

15.
Am J Physiol Cell Physiol ; 324(4): C878-C885, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36878843

RESUMO

Human trophoblast cultures provide powerful tools to model key processes of placental development. In vitro trophoblast studies to date have relied on commercial media that contains nonphysiological levels of nutrients, and the impact of these conditions on trophoblast metabolism and function is unknown. Here, we show that the physiological medium (Plasmax) with nutrient and metabolite concentrations recapitulating human plasma improves human trophoblast stem cell (hTSC) proliferation and differentiation compared with standard medium (DMEM-F12). hTSCs cultured in Plasmax-based medium also show altered glycolytic and mitochondrial metabolism, as well as reduced S-adenosylmethionine/S-adenosyl-homocysteine ratio compared with DMEM-F12-based medium. These findings demonstrate the importance of the nutritional environment for phenotyping cultured human trophoblasts.


Assuntos
Placenta , Trofoblastos , Humanos , Gravidez , Feminino , Placenta/metabolismo , Trofoblastos/metabolismo , Placentação , Diferenciação Celular , Células-Tronco/metabolismo
16.
PLoS Med ; 20(4): e1004225, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-37093852

RESUMO

BACKGROUND: Fetal growth restriction (FGR) is associated with a suboptimal intrauterine environment, which may adversely impact fetal neurodevelopment. However, analysing neurodevelopmental outcomes by observed birthweight fails to differentiate between true FGR and constitutionally small infants and cannot account for iatrogenic intervention. This study aimed to determine the relationship between antenatal FGR and mid-childhood (age 5 to 7 years) educational outcomes. METHODS AND FINDINGS: The Pregnancy Outcome Prediction Study (2008-2012) was a prospective birth cohort conducted in a single maternity hospital in Cambridge, United Kingdom. Clinicians were blinded to the antenatal diagnosis of FGR. FGR was defined as estimated fetal weight (EFW) <10th percentile at approximately 36 weeks of gestation, plus one or more indicators of placental dysfunction, including ultrasonic markers and maternal serum levels of placental biomarkers. A total of 2,754 children delivered at term were divided into 4 groups: FGR, appropriate-for-gestational age (AGA) with markers of placental dysfunction, healthy small-for-gestational age (SGA), and healthy AGA (referent). Educational outcomes (assessed at 5 to 7 years using UK national standards) were assessed with respect to FGR status using regression models adjusted for relevant covariates, including maternal, pregnancy, and socioeconomic factors. Compared to healthy AGA (N = 1,429), children with FGR (N = 250) were at higher risk of "below national standard" educational performance at 6 years (18% versus 11%; aOR 1.68; 95% CI 1.12 to 2.48, p = 0.01). By age 7, children with FGR were more likely to perform below standard in reading (21% versus 15%; aOR 1.46; 95% CI 0.99 to 2.13, p = 0.05), writing (28% versus 23%; aOR 1.46; 95% CI 1.02 to 2.07, p = 0.04), and mathematics (24% versus 16%; aOR 1.49; 95% CI 1.02 to 2.15, p = 0.03). This was consistent whether FGR was defined by ultrasound or biochemical markers. The educational attainment of healthy SGA children (N = 126) was comparable to healthy AGA, although this comparison may be underpowered. Our study design relied on linkage of routinely collected educational data according to nationally standardised metrics; this design allowed a high percentage of eligible participants to be included in the analysis (75%) but excludes those children educated outside of government-funded schools in the UK. Our focus on pragmatic and validated measures of educational attainment does not exclude more subtle effects of the intrauterine environment on specific aspects of neurodevelopment. CONCLUSIONS: Compared to children with normal fetal growth and no markers of placental dysfunction, FGR is associated with poorer educational attainment in mid-childhood.


Assuntos
Retardo do Crescimento Fetal , Placenta , Criança , Recém-Nascido , Gravidez , Feminino , Humanos , Pré-Escolar , Retardo do Crescimento Fetal/diagnóstico , Estudos Prospectivos , Diagnóstico Pré-Natal/métodos , Recém-Nascido Pequeno para a Idade Gestacional , Resultado da Gravidez/epidemiologia , Idade Gestacional , Escolaridade
17.
J Gen Intern Med ; 38(1): 98-106, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35731368

RESUMO

BACKGROUND: Women who use drugs (WWUD) have low rates of contraceptive use and high rates of unintended pregnancy. Drug use is common among women in rural U.S. communities, with limited data on how they utilize reproductive, substance use disorder (SUD), and healthcare services. OBJECTIVE: We determined contraceptive use prevalence among WWUD in rural communities then compared estimates to women from similar rural areas. We investigated characteristics of those using contraceptives, and associations between contraceptive use and SUD treatment, healthcare utilization, and substance use. DESIGN: Rural Opioids Initiative (ROI) - cross-sectional survey using respondent-driven sampling (RDS) involving eight rural U.S. regions (January 2018-March 2020); National Survey on Family Growth (NSFG) - nationally-representative U.S. household reproductive health survey (2017-2019). PARTICIPANTS: Women aged 18-49 with prior 30-day non-prescribed opioid and/or non-opioid injection drug use; fecundity determined by self-reported survey responses. MAIN MEASURES: Unweighted and RDS-weighted prevalence estimates of medical/procedural contraceptive use; chi-squared tests and multi-level linear regressions to test associations. KEY RESULTS: Of 855 women in the ROI, 36.8% (95% CI 33.7-40.1, unweighted) and 38.6% (95% CI 30.7-47.2, weighted) reported contraceptive use, compared to 66% of rural women in the NSFG sample. Among the ROI women, 27% had received prior 30-day SUD treatment via outpatient counseling or inpatient program and these women had increased odds of contraceptive use (aOR 1.50 [95% CI 1.08-2.06]). There was a positive association between contraception use and recent medications for opioid use disorder (aOR 1.34 [95% CI 0.95-1.88]) and prior 6-month primary care utilization (aOR 1.32 [95% CI 0.96-1.82]) that did not meet the threshold for statistical significance. CONCLUSION: WWUD in rural areas reported low contraceptive use; those who recently received SUD treatment had greater odds of contraceptive use. Improvements are needed in expanding reproductive and preventive health within SUD treatment and primary care services in rural communities.


Assuntos
Anticoncepção , População Rural , Gravidez , Feminino , Humanos , Estudos Transversais , Anticoncepcionais/uso terapêutico , Aceitação pelo Paciente de Cuidados de Saúde
18.
Am J Obstet Gynecol ; 228(5S): S1305-S1312, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37164497

RESUMO

Streptococcus agalactiae (group B Streptococcus) colonizes the genital tract of approximately 20% of pregnant women. In the absence of intervention, approximately 1% of infants born to colonized mothers exhibit a clinical infection. This has led to implementation of screening and intervention in the form of intrapartum antibiotic prophylaxis in many countries, including the United States. However, screening has not been introduced in a substantial minority of other countries because of the absence of supportive level 1 evidence, the very large number needed to treat to prevent 1 case, and concerns about antimicrobial resistance. Optimal screening would involve rapid turnaround (to facilitate intrapartum testing) and report antibiotic sensitivity, but no such method exists. There is significant scope for a personalized medicine approach, targeting intrapartum antibiotic prophylaxis to cases at greatest risk, but the pathogen and host factors determining the risk of invasive disease are incompletely understood. Epidemiologic data have indicated the potential of prelabor invasion of the uterus by group B Streptococcus, and metagenomic analysis revealed the presence of group B Streptococcus in the placenta in approximately 5% of pregnant women at term before onset of labor and membrane rupture. However, the determinants and consequences of prelabor invasion of the uterus by group B Streptococcus remain to be established. The vast majority (98%) of invasive neonatal disease is caused by 6 serotypes, and hexavalent vaccines against these serotypes have completed phase 2 trials. However, an obstacle to phase 3 studies is conducting an adequately powered trial to demonstrate clinical effectiveness given that early-onset disease affects approximately 1 in 1000 births in the absence of vaccination.


Assuntos
Trabalho de Parto , Complicações Infecciosas na Gravidez , Infecções Estreptocócicas , Recém-Nascido , Lactente , Gravidez , Feminino , Humanos , Complicações Infecciosas na Gravidez/diagnóstico , Streptococcus agalactiae , Infecções Estreptocócicas/epidemiologia , Infecções Estreptocócicas/diagnóstico , Antibioticoprofilaxia/métodos , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Morbidade
19.
Am J Obstet Gynecol ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37981092

RESUMO

BACKGROUND: Previous studies suggest that gestational diabetes mellitus is associated with poorer cognitive outcomes in children. However, confounding factors, especially maternal body mass index, have been poorly accounted for. OBJECTIVE: This study aimed to examine the independent associations between maternal body mass index, gestational diabetes mellitus status, and educational outcomes. STUDY DESIGN: Antenatal data from a prospective birth cohort (Pregnancy Outcome Prediction Study, 2008-2012, Cambridge, United Kingdom) were linked to mid-childhood educational outcomes (Department for Education, United Kingdom). A total of 3249 children born at term were stratified by maternal gestational diabetes mellitus status and body mass index at booking (<25 vs ≥25 kg/m2). Regression models adjusted for relevant maternal, child, and socioeconomic factors were used to determine associations with academic outcomes at ages of 5 to 7 years. RESULTS: No differences in educational attainment were found between children exposed to gestational diabetes mellitus and nonexposed children. Neither maternal glucose levels measured at 11 to 14 or 24 to 28 weeks, nor acceleration of the fetal abdominal circumference growth velocity were related to educational attainment at ages of 5 to 7 years. Children of mothers with booking body mass index ≥25 kg/m2 (vs <25 kg/m2) were ∼50% more likely to not meet expected educational standards regardless of gestational diabetes mellitus status (age 5: adjusted odds ratio, 1.44; 95% confidence interval, 1.19-1.74; P<.001; age 6: adjusted odds ratio, 1.61; 95% confidence interval, 1.28-2.02; P<.001). The association between maternal body mass index and offspring educational attainment is dose-dependent and robust to stratification by gestational diabetes mellitus status and adjustment for socioeconomic factors. CONCLUSION: Mid-childhood educational attainment is not associated with maternal glucose status. This may provide important reassurance for pregnant women and clinicians. However, maternal body mass index is associated with lower childhood educational attainment and may be modifiable with intervention before or during pregnancy.

20.
Am J Obstet Gynecol ; 229(2): 164.e1-164.e18, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36758709

RESUMO

BACKGROUND: Spontaneous preterm birth is the endpoint of multiple different pathophysiological pathways. Fetal growth restriction, assessed by serial ultrasonic fetal biometry, has been shown to predict both preterm and early-term spontaneous labor. The soluble fms-like tyrosine kinase-1 to placental growth factor ratio is predictive of early-term spontaneous labor, but its association with spontaneous preterm birth is unclear. OBJECTIVE: This study aimed to determine whether maternal serum levels of soluble fms-like tyrosine kinase-1, placental growth factor, and the soluble fms-like tyrosine kinase-1: placental growth factor ratio at 20 and 28 weeks' gestation, and the rate of change in these biomarkers between 20 and 28 weeks were predictive of risk of spontaneous preterm birth. STUDY DESIGN: The biomarkers were measured in maternal serum at 20- and 28-weeks' gestation in women recruited to a prospective cohort of unselected nulliparous women as part of the Pregnancy Outcome Prediction study in Cambridge, United Kingdom. The risk of spontaneous preterm birth was assessed using Cox regression and competing-risks regression. Associations from Cox regression were quantified by the adjusted hazard ratio for a 1 standard deviation higher level of a given biomarker or a 1 standard deviation increase in the marker between 20 and 28 weeks' gestation. A previously identified risk factor, slow femur length growth, was used as an additional predictor of spontaneous preterm birth for the purpose of risk stratification. RESULTS: Of the 3763 participants in the analysis, 95 (2.5%) had spontaneous preterm birth and 54 (1.4%) had medically indicated preterm birth. At 20 weeks' gestation, higher levels of soluble fms-like tyrosine kinase-1 and the soluble fms-like tyrosine kinase-1:placental growth factor ratio were associated with reduced risk of spontaneous preterm birth (adjusted hazard ratio [95% confidence interval], 0.75 [0.61-0.92]; P=.006 and 0.71 [0.59-0.87]; P=.0009, respectively). At 28 weeks' gestation, there was no association between either soluble fms-like tyrosine kinase-1 or placental growth factor and the risk of spontaneous preterm birth, but there was a U-shaped relation with the soluble fms-like tyrosine kinase-1:placental growth factor ratio. However, when the biomarkers were quantified as the rate of increase between 20 and 28 weeks' gestation, there were strong positive associations between spontaneous preterm birth and rate of increase in soluble fms-like tyrosine kinase-1 (1.36 [1.13-1.63]; P=.001) and the soluble fms-like tyrosine kinase-1:placental growth factor ratio (1.50 [1.30-1.73]; P<.0001), and a strong negative association with the rate of increase in placental growth factor (0.71 [0.61-0.82]; P<.0001). Women who were in the highest decile of increase in the soluble fms-like tyrosine kinase-1:placental growth factor ratio and the lowest decile of femur length growth between 20 and 28 weeks' gestation had approximately 9-fold risk of spontaneous preterm birth (9.27 [4.21-20.37]; P<.0001). Competing-risks regression yielded similar results. CONCLUSION: Changing levels of soluble fms-like tyrosine kinase-1 and placental growth factor are indicative of placental dysfunction and are strongly associated with the risk of spontaneous preterm birth, especially when combined with slower fetal femur length growth.


Assuntos
Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Feminino , Recém-Nascido , Humanos , Fator de Crescimento Placentário , Receptor 1 de Fatores de Crescimento do Endotélio Vascular , Nascimento Prematuro/epidemiologia , Idade Gestacional , Estudos Prospectivos , Placenta , Biomarcadores
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