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The heterogeneous nature of eukaryotic replication kinetics and the low efficiency of individual initiation sites make mapping the location and timing of replication initiation in human cells difficult. To address this challenge, we have developed optical replication mapping (ORM), a high-throughput single-molecule approach, and used it to map early-initiation events in human cells. The single-molecule nature of our data and a total of >2,500-fold coverage of the human genome on 27 million fibers averaging â¼300 kb in length allow us to identify initiation sites and their firing probability with high confidence. We find that the distribution of human replication initiation is consistent with inefficient, stochastic activation of heterogeneously distributed potential initiation complexes enriched in accessible chromatin. These observations are consistent with stochastic models of initiation-timing regulation and suggest that stochastic regulation of replication kinetics is a fundamental feature of eukaryotic replication, conserved from yeast to humans.
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Replicação do DNA/genética , Células Eucarióticas/fisiologia , Genoma Humano/genética , Linhagem Celular Tumoral , Cromatina/genética , Período de Replicação do DNA/genética , Genoma Fúngico/genética , Estudo de Associação Genômica Ampla/métodos , Células HeLa , Humanos , Origem de Replicação/genética , Saccharomyces cerevisiae/genética , Sítio de Iniciação de Transcrição/fisiologiaRESUMO
Epigenetic mechanisms have been proposed to play crucial roles in mammalian development, but their precise functions are only partially understood. To investigate epigenetic regulation of embryonic development, we differentiated human embryonic stem cells into mesendoderm, neural progenitor cells, trophoblast-like cells, and mesenchymal stem cells and systematically characterized DNA methylation, chromatin modifications, and the transcriptome in each lineage. We found that promoters that are active in early developmental stages tend to be CG rich and mainly engage H3K27me3 upon silencing in nonexpressing lineages. By contrast, promoters for genes expressed preferentially at later stages are often CG poor and primarily employ DNA methylation upon repression. Interestingly, the early developmental regulatory genes are often located in large genomic domains that are generally devoid of DNA methylation in most lineages, which we termed DNA methylation valleys (DMVs). Our results suggest that distinct epigenetic mechanisms regulate early and late stages of ES cell differentiation.
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Metilação de DNA , Células-Tronco Embrionárias/metabolismo , Epigenômica , Regulação da Expressão Gênica no Desenvolvimento , Animais , Diferenciação Celular , Cromatina/metabolismo , Ilhas de CpG , Células-Tronco Embrionárias/citologia , Histonas/metabolismo , Humanos , Metilação , Neoplasias/genética , Regiões Promotoras Genéticas , Peixe-Zebra/embriologiaRESUMO
DNA replication occurs through an intricately regulated series of molecular events and is fundamental for genome stability1,2. At present, it is unknown how the locations of replication origins are determined in the human genome. Here we dissect the role of topologically associating domains (TADs)3-6, subTADs7 and loops8 in the positioning of replication initiation zones (IZs). We stratify TADs and subTADs by the presence of corner-dots indicative of loops and the orientation of CTCF motifs. We find that high-efficiency, early replicating IZs localize to boundaries between adjacent corner-dot TADs anchored by high-density arrays of divergently and convergently oriented CTCF motifs. By contrast, low-efficiency IZs localize to weaker dotless boundaries. Following ablation of cohesin-mediated loop extrusion during G1, high-efficiency IZs become diffuse and delocalized at boundaries with complex CTCF motif orientations. Moreover, G1 knockdown of the cohesin unloading factor WAPL results in gained long-range loops and narrowed localization of IZs at the same boundaries. Finally, targeted deletion or insertion of specific boundaries causes local replication timing shifts consistent with IZ loss or gain, respectively. Our data support a model in which cohesin-mediated loop extrusion and stalling at a subset of genetically encoded TAD and subTAD boundaries is an essential determinant of the locations of replication origins in human S phase.
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Proteínas de Ciclo Celular , Cromatina , Proteínas Cromossômicas não Histona , Origem de Replicação , Proteínas de Ciclo Celular/metabolismo , Cromatina/genética , Proteínas Cromossômicas não Histona/metabolismo , Replicação do DNA , Humanos , Origem de Replicação/genética , Fase S , CoesinasRESUMO
Acute myeloid leukaemia (AML) represents a set of heterogeneous myeloid malignancies, and hallmarks include mutations in epigenetic modifiers, transcription factors and kinases1-5. The extent to which mutations in AML drive alterations in chromatin 3D structure and contribute to myeloid transformation is unclear. Here we use Hi-C and whole-genome sequencing to analyse 25 samples from patients with AML and 7 samples from healthy donors. Recurrent and subtype-specific alterations in A/B compartments, topologically associating domains and chromatin loops were identified. RNA sequencing, ATAC with sequencing and CUT&Tag for CTCF, H3K27ac and H3K27me3 in the same AML samples also revealed extensive and recurrent AML-specific promoter-enhancer and promoter-silencer loops. We validated the role of repressive loops on their target genes by CRISPR deletion and interference. Structural variation-induced enhancer-hijacking and silencer-hijacking events were further identified in AML samples. Hijacked enhancers play a part in AML cell growth, as demonstrated by CRISPR screening, whereas hijacked silencers have a downregulating role, as evidenced by CRISPR-interference-mediated de-repression. Finally, whole-genome bisulfite sequencing of 20 AML and normal samples revealed the delicate relationship between DNA methylation, CTCF binding and 3D genome structure. Treatment of AML cells with a DNA hypomethylating agent and triple knockdown of DNMT1, DNMT3A and DNMT3B enabled the manipulation of DNA methylation to revert 3D genome organization and gene expression. Overall, this study provides a resource for leukaemia studies and highlights the role of repressive loops and hijacked cis elements in human diseases.
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Genoma Humano , Leucemia Mieloide Aguda , Humanos , Cromatina/genética , Metilação de DNA , Leucemia Mieloide Aguda/genética , Genoma Humano/genética , Regiões Promotoras Genéticas , Elementos Facilitadores Genéticos , Inativação Gênica , Reprodutibilidade dos Testes , Sistemas CRISPR-Cas , Análise de Sequência , DNA (Citosina-5-)-Metiltransferases , Regulação Leucêmica da Expressão GênicaRESUMO
The zebrafish (Danio rerio) has been widely used in the study of human disease and development, and about 70% of the protein-coding genes are conserved between the two species1. However, studies in zebrafish remain constrained by the sparse annotation of functional control elements in the zebrafish genome. Here we performed RNA sequencing, assay for transposase-accessible chromatin using sequencing (ATAC-seq), chromatin immunoprecipitation with sequencing, whole-genome bisulfite sequencing, and chromosome conformation capture (Hi-C) experiments in up to eleven adult and two embryonic tissues to generate a comprehensive map of transcriptomes, cis-regulatory elements, heterochromatin, methylomes and 3D genome organization in the zebrafish Tübingen reference strain. A comparison of zebrafish, human and mouse regulatory elements enabled the identification of both evolutionarily conserved and species-specific regulatory sequences and networks. We observed enrichment of evolutionary breakpoints at topologically associating domain boundaries, which were correlated with strong histone H3 lysine 4 trimethylation (H3K4me3) and CCCTC-binding factor (CTCF) signals. We performed single-cell ATAC-seq in zebrafish brain, which delineated 25 different clusters of cell types. By combining long-read DNA sequencing and Hi-C, we assembled the sex-determining chromosome 4 de novo. Overall, our work provides an additional epigenomic anchor for the functional annotation of vertebrate genomes and the study of evolutionarily conserved elements of 3D genome organization.
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Genoma/genética , Imageamento Tridimensional , Imagem Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Peixe-Zebra/genética , Animais , Encéfalo/metabolismo , Sequência Conservada/genética , Metilação de DNA , Elementos Facilitadores Genéticos/genética , Epigênese Genética , Evolução Molecular , Feminino , Perfilação da Expressão Gênica , Redes Reguladoras de Genes/genética , Heterocromatina/química , Heterocromatina/genética , Heterocromatina/metabolismo , Humanos , Masculino , Camundongos , Especificidade de Órgãos , Regiões Promotoras Genéticas/genética , Análise de Célula Única , Especificidade da EspécieRESUMO
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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The Encyclopedia of DNA Elements (ENCODE) project has established a genomic resource for mammalian development, profiling a diverse panel of mouse tissues at 8 developmental stages from 10.5 days after conception until birth, including transcriptomes, methylomes and chromatin states. Here we systematically examined the state and accessibility of chromatin in the developing mouse fetus. In total we performed 1,128 chromatin immunoprecipitation with sequencing (ChIP-seq) assays for histone modifications and 132 assay for transposase-accessible chromatin using sequencing (ATAC-seq) assays for chromatin accessibility across 72 distinct tissue-stages. We used integrative analysis to develop a unified set of chromatin state annotations, infer the identities of dynamic enhancers and key transcriptional regulators, and characterize the relationship between chromatin state and accessibility during developmental gene regulation. We also leveraged these data to link enhancers to putative target genes and demonstrate tissue-specific enrichments of sequence variants associated with disease in humans. The mouse ENCODE data sets provide a compendium of resources for biomedical researchers and achieve, to our knowledge, the most comprehensive view of chromatin dynamics during mammalian fetal development to date.
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Cromatina/genética , Cromatina/metabolismo , Conjuntos de Dados como Assunto , Desenvolvimento Fetal/genética , Histonas/metabolismo , Anotação de Sequência Molecular , Sequências Reguladoras de Ácido Nucleico/genética , Animais , Cromatina/química , Sequenciamento de Cromatina por Imunoprecipitação , Doença/genética , Elementos Facilitadores Genéticos/genética , Feminino , Regulação da Expressão Gênica no Desenvolvimento/genética , Variação Genética , Histonas/química , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Especificidade de Órgãos/genética , Reprodutibilidade dos Testes , Transposases/metabolismoRESUMO
Transposable elements (TEs) encode regulatory elements that impact gene expression in multiple species, yet a comprehensive analysis of zebrafish TEs in the context of gene regulation is lacking. Here, we systematically investigate the epigenomic and transcriptomic landscape of TEs across 11 adult zebrafish tissues using multidimensional sequencing data. We find that TEs contribute substantially to a diverse array of regulatory elements in the zebrafish genome and that 37% of TEs are positioned in active regulatory states in adult zebrafish tissues. We identify TE subfamilies enriched in highly specific regulatory elements among different tissues. We use transcript assembly to discover TE-derived transcriptional units expressed across tissues. Finally, we show that novel TE-derived promoters can initiate tissue-specific transcription of alternate gene isoforms. This work provides a comprehensive profile of TE activity across normal zebrafish tissues, shedding light on mechanisms underlying the regulation of gene expression in this widely used model organism.
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Elementos de DNA Transponíveis , Epigenômica , Animais , Elementos de DNA Transponíveis/genética , Regiões Promotoras Genéticas , Sequências Reguladoras de Ácido Nucleico , Peixe-Zebra/genéticaRESUMO
Diabetic nephropathy (DN) has become the main cause of end-stage renal disease worldwide, causing significant health problems. Early diagnosis of the disease is quite inadequate. To screen urine biomarkers of DN and explore its potential mechanism, this study collected urine from 87 patients with type 2 diabetes mellitus (which will be classified into normal albuminuria, microalbuminuria, and macroalbuminuria groups) and 38 healthy subjects. Twelve individuals from each group were then randomly selected as the screening cohort for proteomics analysis and the rest as the validation cohort. The results showed that humoral immune response, complement activation, complement and coagulation cascades, renin-angiotensin system, and cell adhesion molecules were closely related to the progression of DN. Five overlapping proteins (KLK1, CSPG4, PLAU, SERPINA3, and ALB) were identified as potential biomarkers by machine learning methods. Among them, KLK1 and CSPG4 were positively correlated with the urinary albumin to creatinine ratio (UACR), and SERPINA3 was negatively correlated with the UACR, which were validated by enzyme-linked immunosorbent assay (ELISA). This study provides new insights into disease mechanisms and biomarkers for early diagnosis of DN.
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Albuminúria , Biomarcadores , Diabetes Mellitus Tipo 2 , Nefropatias Diabéticas , Aprendizado de Máquina , Proteômica , Humanos , Nefropatias Diabéticas/urina , Nefropatias Diabéticas/diagnóstico , Biomarcadores/urina , Proteômica/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Albuminúria/urina , Albuminúria/diagnóstico , Diabetes Mellitus Tipo 2/urina , Diabetes Mellitus Tipo 2/complicações , Serpinas/urina , Calicreínas/urina , Idoso , Estudos de Casos e Controles , Creatinina/urina , CininogêniosRESUMO
Perigonadal adipose tissue is a homogeneous white adipose tissue (WAT) in adult male mice without any brown adipose tissue (BAT). However, there are congenital differences in the gonads between male and female mice. Whether heterogeneity existed in perigonadal adipose tissues (ATs) in female mice remains unknown. This study reported a perigonadal brown-like AT located between abdominal lymph nodes and the uterine cervix in female mice, termed lymph node-cervical adipose tissue (LNCAT). Its counterpart, lymph node-prostatic adipose tissue (LNPAT), exhibited white phenotype in adult virgin male mice. When exposed to cold, LNCAT/LNPAT increased uncoupling protein 1 (UCP1) expression via activation of tyrosine hydroxylase (TH), in which abdominal lymph nodes were involved. Interestingly, the UCP1 expression in LNCAT/LNPAT varied under different reproductive stages. The UCP1 expression in LNCAT was upregulated at early pregnancy, declined at midlate pregnancy, and reverted in weaning dams. Mating behavior stimulated LNPAT browning in male mice. We found that androgen but not estrogen or progesterone inhibited UCP1 expression in LNCAT. Androgen administration reversed the castration-induced LNPAT browning. Our results identified a perigonadal brown-like AT in female mice and characterized its UCP1 expression patterns under various conditions.NEW & NOTEWORTHY A novel perigonadal brown-like AT (LNCAT) of female mice was identified. Abdominal lymph nodes were involved in cold-induced browning in this newly discovered adipose tissue. The UCP1 expression in LNCAT/LNPAT was also related to ages, sexes, and reproductive stages, in which androgen acted as an inhibitor role.
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Tecido Adiposo Marrom , Colo do Útero , Linfonodos , Próstata , Proteína Desacopladora 1 , Animais , Masculino , Feminino , Camundongos , Linfonodos/metabolismo , Proteína Desacopladora 1/metabolismo , Proteína Desacopladora 1/genética , Tecido Adiposo Marrom/metabolismo , Colo do Útero/metabolismo , Próstata/metabolismo , Gravidez , Tecido Adiposo Branco/metabolismo , Camundongos Endogâmicos C57BL , Tecido Adiposo/metabolismo , Androgênios/farmacologia , Androgênios/metabolismo , Comportamento Sexual Animal/fisiologiaRESUMO
Possessing a unique combination of properties that are traditionally contradictory in other natural or synthetical materials, Ga-based liquid metals (LMs) exhibit low mechanical stiffness and flowability like a liquid, with good electrical and thermal conductivity like metal, as well as good biocompatibility and room-temperature phase transformation. These remarkable properties have paved the way for the development of novel reconfigurable or stretchable electronics and devices. Despite these outstanding properties, the easy oxidation, high surface tension, and low rheological viscosity of LMs have presented formidable challenges in high-resolution patterning. To address this challenge, various surface modifications or additives have been employed to tailor the oxidation state, viscosity, and patterning capability of LMs. One effective approach for LM patterning is breaking down LMs into microparticles known as liquid metal particles (LMPs). This facilitates LM patterning using conventional techniques such as stencil, screening, or inkjet printing. Judiciously formulated photo-curable LMP inks or the introduction of an adhesive seed layer combined with a modified lift-off process further provide the micrometer-level LM patterns. Incorporating porous and adhesive substrates in LM-based electronics allows direct interfacing with the skin for robust and long-term monitoring of physiological signals. Combined with self-healing polymers in the form of substrates or composites, LM-based electronics can provide mechanical-robust devices to heal after damage for working in harsh environments. This review provides the latest advances in LM-based composites, fabrication methods, and their novel and unique applications in stretchable or reconfigurable sensors and resulting integrated systems. It is believed that the advancements in LM-based material preparation and high-resolution techniques have opened up opportunities for customized designs of LM-based stretchable sensors, as well as multifunctional, reconfigurable, highly integrated, and even standalone systems.
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OBJECTIVE: Diabetes and other metabolic and inflammatory comorbidities are highly associated with osteoarthritis (OA). However, whether early-life hyperglycemia exposure affects susceptibility to long-term OA is still unknown. The purpose of this study was to explore the fetal origins of OA and provide insights into early-life safeguarding for individual health. METHOD: This study utilized streptozotocin to induce intrauterine hyperglycemia and performed destabilization of the medial meniscus surgery on the knee joints of the offspring mice to induce accelerated OA. Cartilage degeneration-related markers, as well as the expression levels of mitochondrial respiratory chain complexes and mitophagy genes in the adult offspring mice, were investigated. In vitro, mitochondrial function and mitophagy of chondrocyte C28/I2 cells stimulated under high glucose conditions were also evaluated. The methylation levels of the sirt3 gene promoter region in the articular cartilage of intrauterine hyperglycemia-exposed offspring mice were further analyzed. RESULTS: In this study, we found that the intrauterine hyperglycemic environment could lead to an increase in individual susceptibility to OA in late adulthood, mainly due to persistently low levels of Sirt3 expression. Downregulation of Sirt3 causes impaired mitophagy in chondrocytes and abnormal mitochondrial respiratory function due to a failure to clear aged and damaged mitochondria in a timely manner. Overexpressing Sirt3 at the cellular level or using Sirt3 agonists like Honokiol in mouse models can partially rescue mitophagy disorders caused by the hyperglycemic environment and thus alleviate the progression of OA. CONCLUSION: Our study revealed a significantly increased susceptibility to OA in the gestational diabetes mellitus offspring, which is partly attributed to exposure to adverse factors in utero and ultimately to the onset of disease via epigenetic modulation.
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Condrócitos , Hiperglicemia , Mitocôndrias , Sirtuína 3 , Animais , Sirtuína 3/metabolismo , Sirtuína 3/genética , Hiperglicemia/metabolismo , Camundongos , Feminino , Gravidez , Condrócitos/metabolismo , Mitocôndrias/metabolismo , Mitofagia , Efeitos Tardios da Exposição Pré-Natal , Cartilagem Articular/metabolismo , Diabetes Mellitus Experimental/metabolismo , Osteoartrite/metabolismo , Osteoartrite/etiologia , Osteoartrite/genética , Metilação de DNA , Osteoartrite do Joelho/metabolismo , Osteoartrite do Joelho/etiologia , Osteoartrite do Joelho/genéticaRESUMO
Alzheimer's disease (AD) is a multifactorial neurodegenerative disease that lacks convenient and accessible peripheral blood diagnostic markers and effective drugs. Metabolic dysfunction is one of AD risk factors, which leaded to alterations of various metabolites in the body. Pathological changes of the brain can be reflected in blood metabolites that are expected to explain the disease mechanisms or be candidate biomarkers. The aim of this study was to investigate the changes of targeted metabolites within peripheral blood of AD mouse model, with the purpose of exploring the disease mechanism and potential biomarkers. Targeted metabolomics was used to quantify 256 metabolites in serum of triple transgenic AD (3 × Tg-AD) male mice. Compared with controls, 49 differential metabolites represented dysregulation in purine, pyrimidine, tryptophan, cysteine and methionine and glycerophospholipid metabolism. Among them, adenosine, serotonin, N-acetyl-5-hydroxytryptamine, and acetylcholine play a key role in regulating neural transmitter network. The alteration of S-adenosine-L-homocysteine, S-adenosine-L-methionine, and trimethylamine-N-oxide in AD mice serum can served as indicator of AD risk. The results revealed the changes of metabolites in serum, suggesting that metabolic dysregulation in periphery in AD mice may be related to the disturbances in neuroinhibition, the serotonergic system, sleep function, the cholinergic system, and the gut microbiota. This study provides novel insights into the dysregulation of several key metabolites and metabolic pathways in AD, presenting potential avenues for future research and the development of peripheral biomarkers.
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Doença de Alzheimer , Doenças Neurodegenerativas , Animais , Masculino , Camundongos , Adenosina , Biomarcadores , Metabolômica/métodos , Camundongos Transgênicos , S-Adenosil-Homocisteína/químicaRESUMO
BACKGROUND AND PURPOSE: Hereditary transthyretin-mediated amyloidosis with polyneuropathy (ATTRv-PN [v for variant]) is a rare, progressive disease associated with multisystemic impairments. This study assessed the real-world outcomes of patients with ATTRv-PN who switched from tafamidis to patisiran, as well as the reasons for the treatment switch. METHODS: This was a retrospective chart review study at a large expert referral center. Data were extracted from medical charts of patients with ATTRv-PN who switched from tafamidis to patisiran on or before 30 August 2019. Data elements included demographic and clinical characteristics, rationale for switch, and disease measures evaluated from tafamidis initiation through the 12-month patisiran treatment period. RESULTS: Among the 24 patients with ATTRv-PN included in the study, 50.0% had a V30M variant, and the mean (SD) age was 67.3 (8.0) years. During tafamidis treatment (mean [SD] = 30.1 [17.5] months) before switching to patisiran, patients worsened across multiple polyneuropathy measures, including walking ability, Neuropathy Impairment Score, and autonomic function. Neuropathic disease progression on tafamidis was the principal reason for switching to patisiran. After 12 months on patisiran (mean [SD] = 11.7 [1.4] months), patients experienced attenuated disease progression or improvement in the aforementioned measures of polyneuropathy. CONCLUSIONS: Switching from tafamidis to patisiran attenuated the rate of functional decline, and most patients experienced stabilization or improvement of at least one polyneuropathy measure within 12 months of patisiran treatment. Timely switch from tafamidis to patisiran can be beneficial to avoid rapid disease progression in patients with ATTRv-PN.
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Neuropatias Amiloides Familiares , Benzoxazóis , Polineuropatias , Humanos , Neuropatias Amiloides Familiares/tratamento farmacológico , Neuropatias Amiloides Familiares/complicações , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Benzoxazóis/uso terapêutico , Polineuropatias/tratamento farmacológico , Substituição de Medicamentos , Resultado do Tratamento , RNA Interferente PequenoRESUMO
INTRODUCTION: The correlation between radiation exposure before pregnancy and abnormal birth weight has been previously proven. However, for large-for-gestational-age (LGA) babies in women exposed to radiation before becoming pregnant, there is no prediction model yet. MATERIAL AND METHODS: The data were collected from the National Free Preconception Health Examination Project in China. A sum of 455 neonates (42 SGA births and 423 non-LGA births) were included. A training set (n = 319) and a test set (n = 136) were created from the dataset at random. To develop prediction models for LGA neonates, conventional logistic regression (LR) method and six machine learning methods were used in this study. Recursive feature elimination approach was performed by choosing 10 features which made a big contribution to the prediction models. And the Shapley Additive Explanation model was applied to interpret the most important characteristics that affected forecast outputs. RESULTS: The random forest (RF) model had the highest average area under the receiver-operating-characteristic curve (AUC) for predicting LGA in the test set (0.843, 95% confidence interval [CI]: 0.714-0.974). Except for the logistic regression model (AUC: 0.603, 95%CI: 0.440-0.767), other models' AUCs displayed well. Thereinto, the RF algorithm's final prediction model using 10 characteristics achieved an average AUC of 0.821 (95% CI: 0.693-0.949). CONCLUSION: The prediction model based on machine learning might be a promising tool for the prenatal prediction of LGA births in women with radiation exposure before pregnancy.
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Aprendizado de Máquina , Humanos , Feminino , Gravidez , Recém-Nascido , Adulto , China , Exposição à Radiação/efeitos adversos , Peso ao Nascer , Macrossomia FetalRESUMO
Aiming at the problems of obscure clinical auscultation features of pulmonary hypertension associated with congenital heart disease and the complexity of existing machine-aided diagnostic algorithms, an algorithm based on the statistical characteristics of the high-frequency components of the second heart sound signal is proposed. Firstly, an endpoint detection adaptive segmentation method is employed to extract the second heart sounds. Subsequently, the high-frequency component of the heart sound is decomposed using the discrete wavelet transform. Statistical features including the Hurst exponent, Lempel-Ziv information and sample entropy are extracted from this component. Finally, the extracted features are utilized to train an extreme gradient boosting algorithm (XGBoost) classifier, which achieves an accuracy of 80.45% in triple classification. Notably, this method eliminates the need for a noise reduction algorithm, allows for swift feature extraction, and achieves effective multi-classification using only three features. It is promising for early screening of pulmonary hypertension associated with congenital heart disease.
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Cardiopatias Congênitas , Ruídos Cardíacos , Hipertensão Pulmonar , Humanos , Processamento de Sinais Assistido por Computador , Hipertensão Pulmonar/diagnóstico , Algoritmos , Cardiopatias Congênitas/complicações , Cardiopatias Congênitas/diagnósticoRESUMO
The multi-window time-frequency reassignment helps to improve the time-frequency resolution of bark-frequency spectral coefficient (BFSC) analysis of heart sounds. For this purpose, a new heart sound classification algorithm combining feature extraction based on multi-window time-frequency reassignment BFSC with deep learning was proposed in this paper. Firstly, the randomly intercepted heart sound segments are preprocessed with amplitude normalization, the heart sounds were framed and time-frequency rearrangement based on short-time Fourier transforms were computed using multiple orthogonal windows. A smooth spectrum estimate is calculated by arithmetic averaging each of the obtained independent spectra. Finally, the BFSC of reassignment spectrum is extracted as a feature by the Bark filter bank. In this paper, convolutional network and recurrent neural network are used as classifiers for model comparison and performance evaluation of the extracted features. Eventually, the multi-window time-frequency rearrangement improved BFSC method extracts more discriminative features, with a binary classification accuracy of 0.936, a sensitivity of 0.946, and a specificity of 0.922. These results present that the algorithm proposed in this paper does not need to segment the heart sounds and randomly intercepts the heart sound segments, which greatly simplifies the computational process and is expected to be used for screening of congenital heart disease.
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Cardiopatias Congênitas , Ruídos Cardíacos , Humanos , Casca de Planta , Algoritmos , Redes Neurais de ComputaçãoRESUMO
Physical forces are important participants in the cellular dynamics that shape developing organs. During heart formation, for example, contractility and blood flow generate biomechanical cues that influence patterns of cell behavior. Here, we address the interplay between function and form during the assembly of the cardiac outflow tract (OFT), a crucial connection between the heart and vasculature that develops while circulation is under way. In zebrafish, we find that the OFT expands via accrual of both endocardial and myocardial cells. However, when cardiac function is disrupted, OFT endocardial growth ceases, accompanied by reduced proliferation and reduced addition of cells from adjacent vessels. The flow-responsive TGFß receptor Acvrl1 is required for addition of endocardial cells, but not for their proliferation, indicating distinct modes of function-dependent regulation for each of these essential cell behaviors. Together, our results indicate that cardiac function modulates OFT morphogenesis by triggering endocardial cell accumulation that induces OFT lumen expansion and shapes OFT dimensions. Moreover, these morphogenetic mechanisms provide new perspectives regarding the potential causes of cardiac birth defects.
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Endocárdio/metabolismo , Coração/fisiologia , Peixe-Zebra/metabolismo , Receptores de Ativinas/antagonistas & inibidores , Receptores de Ativinas/genética , Receptores de Ativinas/metabolismo , Animais , Animais Geneticamente Modificados/crescimento & desenvolvimento , Animais Geneticamente Modificados/metabolismo , Proliferação de Células , Embrião não Mamífero/citologia , Embrião não Mamífero/metabolismo , Endocárdio/citologia , Coração/anatomia & histologia , Coração/crescimento & desenvolvimento , Morfolinos/metabolismo , Troponina T/antagonistas & inibidores , Troponina T/genética , Troponina T/metabolismo , Peixe-Zebra/crescimento & desenvolvimento , Proteínas de Peixe-Zebra/antagonistas & inibidores , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismoRESUMO
OBJECTIVE: Hypothalamic dysfunction is characterized by complex aetiologies, multiple forms of onset and various clinical symptoms. This study aims to explore the clinical and metabolic characteristics of hypothalamic dysfunction in Chinese children and adolescents. DESIGN: This study is a single-centre, retrospective study that covers patients from 1989 to 2019. PATIENTS: We included 40 children and adolescents with hypothalamic dysfunction from our medical centre in Beijing, China. RESULTS: Intracranial tumour (37.5%) was the most common aetiology of children and adolescents with hypothalamic dysfunction, especially germ cell tumours, hypopituitarism (82.5%), weight gain (72.5%) and central diabetes insipidus (70.0%) were the most common symptoms in these patients. Furthermore, serum alanine aminotransferase, aspartate aminotransferase, γ-glutamyl transpeptidase, uric acid, total cholesterol, triglycerides and low-density lipoprotein cholesterol was significantly higher in hypothalamic dysfunction patients than sex- and age-matched controls and sex, age and body mass index (BMI)-matched controls (all p < 0.05). However, albumin and high-density lipoprotein cholesterol were lower (p< 0.05). Moreover, 95% (38/40) of the patients had metabolic diseases. In addition, the incidence of dyslipidaemia and hyperuricemia in children and adolescents with hypothalamic dysfunction was significantly higher than both sex- and age-matched controls and sex-, age- and BMI-matched controls (both p < 0.05) as well. CONCLUSIONS: Intracranial tumour was the most common aetiology in children and adolescents with hypothalamic dysfunction. In addition, these patients presented a worse metabolic profile on average than healthy patients.
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Colesterol , Criança , Humanos , Adolescente , Estudos Retrospectivos , China/epidemiologiaRESUMO
INTRODUCTION: Idiopathic hypothalamic dysfunction (IHD) is a rare syndrome with heterogeneous clinical symptoms. This study aimed to systematically review the clinical features and potential treatment of IHD based on our case series and literature. METHODS: We analysed six recently diagnosed cases of IHD in Peking Union Medical College Hospital and conducted a systematic review of IHD case studies published before August 25, 2021, using the PubMed/Medline database. All 12 articles that met the definition of IHD and provided individual clinical data were reviewed. RESULTS: Of the 19 cases reviewed (13 from the literature and 6 from our centre), the median age at onset was 6 years. Obesity/weight gain (n = 14, 73.7%) and electrolyte abnormalities (n = 14, 73.7%) were the most common hypothalamic physiological dysfunction, followed by autonomic dysregulation (n = 13, 68.4%) and adipsia (n = 13, 68.4%). The most common initial symptom of young patients was obesity/weight gain, whereas the initial symptoms of the three adult patients were hypothalamic amenorrhoea, delayed sexual development, and polydipsia. 11 (57.9%) patients had obesity, and three of our patients were diagnosed with metabolic syndrome in late adolescence or early adulthood. Three of our cases diagnosed with growth hormone deficiency received growth hormone therapy, which exerted positive effects on growth promotion and weight stabilization. CONCLUSION: Although obesity/weight gain was the most common symptom of IHD, uncommon initial symptoms such as electrolyte abnormalities and sexual disorders also require attention, especially in patients with late childhood- or adult-onset IHD. Consistent monitoring of metabolic profiles is recommended. Positive effects of growth hormone replacement therapy on growth and weight were observed, but more extensive cohort studies are required to confirm its efficacy and safety.