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1.
J Ovarian Res ; 17(1): 32, 2024 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-38310280

RESUMO

BACKGROUND: The etiology of premature ovarian insufficiency, that is, the loss of ovarian activity before 40 years of age, is complex. Studies suggest that genetic factors are involved in 20-25% of cases. The aim of this study was to explore the oligogenic basis of premature ovarian insufficiency. RESULTS: Whole-exome sequencing of 93 patients with POI and whole-genome sequencing of 465 controls were performed. In the gene-burden analysis, multiple genetic variants, including those associated with DNA damage repair and meiosis, were more common in participants with premature ovarian insufficiency than in controls. The ORVAL-platform analysis confirmed the pathogenicity of the RAD52 and MSH6 combination. CONCLUSIONS: The results of this study indicate that oligogenic inheritance is an important cause of premature ovarian insufficiency and provide insights into the biological mechanisms underlying premature ovarian insufficiency.


Assuntos
Menopausa Precoce , Insuficiência Ovariana Primária , Feminino , Humanos , Insuficiência Ovariana Primária/genética , Menopausa Precoce/genética
2.
Front Endocrinol (Lausanne) ; 14: 1285667, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38149096

RESUMO

Introduction: The number of primordial follicles (PFs) in mammals determines the ovarian reserve, and impairment of primordial follicle formation (PFF) will cause premature ovarian insufficiency (POI). Methods: By analyzing public single-cell RNA sequencing performed during PFF on mice and human ovaries, we identified novel functional genes and novel ligand-receptor interaction during PFF. Based on immunofluorescence and in vitro ovarian culture, we confirmed mechanisms of genes and ligand-receptor interaction in PFF. We also applied whole exome sequencing (WES) in 93 cases with POI and whole genome sequencing (WGS) in 465 controls. Variants in POI patients were further investigated by in silico analysis and functional verification. Results: We revealed ANXA7 (annexin A7) and GTF2F1 (general transcription factor IIF subunit 1) in germ cells to be novel potentially genes in promoting PFF. Ligand Mdk (midkine) in germ cells and its receptor Sdc1 (syndecan 1) in granulosa cells are novel interaction crucial for PFF. Based on immunofluorescence, we confirmed significant up-regulation of ANXA7 in PFs compared with germline cysts, and uniform expression of GTF2F1, MDK and SDC1 during PFF, in 25 weeks human fetal ovary. In vitro investigation indicated that Anxa7 and Gtf2f1 are vital for mice PFF by regulating Jak/Stat3 and Jnk signaling pathways, respectively. Ligand-receptor (Mdk-Sdc1) are crucial for PFF by regulating Pi3k-akt signaling pathway. Two heterozygous variants in GTF2F1, and one heterozygous variants in SDC1 were identified in cases, but no variant were identified in controls. The protein level of GTF2F1 or SDC1 in POI cases are significantly lower than that of controls, indicating the pathogenic effects of the two genes on ovarian function were dosage dependent. Discussion: Our study identified novel genes and novel ligand-receptor interaction during PFF, and further expanding the genetic architecture of POI.


Assuntos
Menopausa Precoce , Insuficiência Ovariana Primária , Feminino , Humanos , Animais , Camundongos , Sequenciamento do Exoma , Fosfatidilinositol 3-Quinases/metabolismo , Ligantes , Análise da Expressão Gênica de Célula Única , Folículo Ovariano/metabolismo , Insuficiência Ovariana Primária/genética , Mamíferos/genética
3.
Cell Cycle ; 22(21-22): 2436-2448, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-38146657

RESUMO

Endometriosis is a benign high prevalent disease exhibiting malignant features. However, the underlying pathogenesis and key molecules of endometriosis remain unclear. By integrating and analysis of existing expression profile datasets, we identified coxsackie and adenovirus receptor (CXADR), as a novel key gene in endometriosis. Based on the results of immunohistochemistry (IHC), we confirmed significant down-regulation of CXADR in ectopic endometrial tissues obtained from women with endometriosis compared with healthy controls. Further in vitro investigation indicated that CXADR regulated the stability and function of the phosphatases and AKT inhibitors PHLPP2 (pleckstrin homology domain and leucine-rich repeat protein phosphatase 2) and PTEN (phosphatase and tensin homolog). Loss of CXADR led to phosphorylation of AKT and glycogen synthase kinase-3ß (GSK-3ß), which resulted in stabilization of an epithelial-mesenchymal transition (EMT) factor, SNAIL1 (snail family transcriptional repressor 1). Therefore, EMT processs was induced, and the proliferation, migration and invasion of Ishikawa cells were enhanced. Over-expression of CXADR showed opposite effects. These findings suggest a previously undefined role of AKT/GSK-3ß signaling axis in regulating EMT and reveal the involvement of a CXADR-induced EMT, in pathogenic progression of endometriosis.


Assuntos
Endometriose , Proteínas Proto-Oncogênicas c-akt , Feminino , Humanos , Moléculas de Adesão Celular , Linhagem Celular Tumoral , Movimento Celular , Endometriose/genética , Transição Epitelial-Mesenquimal , Glicogênio Sintase Quinase 3 beta , Fosfoproteínas Fosfatases/farmacologia , Monoéster Fosfórico Hidrolases , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fatores de Transcrição da Família Snail/genética , Fatores de Transcrição da Família Snail/metabolismo
4.
IEEE Trans Med Imaging ; 42(12): 3805-3816, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37651491

RESUMO

Involuntary motion of the heart remains a challenge for cardiac computed tomography (CT) imaging. Although the electrocardiogram (ECG) gating strategy is widely adopted to perform CT scans at the quasi-quiescent cardiac phase, motion-induced artifacts are still unavoidable for patients with high heart rates or irregular rhythms. Dynamic cardiac CT, which provides functional information of the heart, suffers even more severe motion artifacts. In this paper, we develop a deep learning based framework for motion artifact reduction in dynamic cardiac CT. First, we build a PAD (Pseudo All-phase clinical-Dataset) based on a whole-heart motion model and single-phase cardiac CT images. This dataset provides dynamic CT images with realistic-looking motion artifacts that help to develop data-driven approaches. Second, we formulate the problem of motion artifact reduction as a video deblurring task according to its dynamic nature. A novel TT U-Net (Temporal Transformer U-Net) is proposed to excavate the spatiotemporal features for better motion artifact reduction. The self-attention mechanism along the temporal dimension effectively encodes motion information and thus aids image recovery. Experiments show that the TT U-Net trained on the proposed PAD performs well on clinical CT scans, which substantiates the effectiveness and fine generalization ability of our method. The source code, trained models, and dynamic demo will be available at https://github.com/ivy9092111111/TT-U-Net.


Assuntos
Artefatos , Tomografia Computadorizada por Raios X , Humanos , Movimento (Física) , Tomografia Computadorizada por Raios X/métodos , Coração/diagnóstico por imagem , Eletrocardiografia , Processamento de Imagem Assistida por Computador/métodos
5.
Artigo em Inglês | MEDLINE | ID: mdl-36141871

RESUMO

Cancer has become a major threat to global health care. With the development of computer science, artificial intelligence (AI) has been widely applied in histopathological images (HI) analysis. This study analyzed the publications of AI in HI from 2001 to 2021 by bibliometrics, exploring the research status and the potential popular directions in the future. A total of 2844 publications from the Web of Science Core Collection were included in the bibliometric analysis. The country/region, institution, author, journal, keyword, and references were analyzed by using VOSviewer and CiteSpace. The results showed that the number of publications has grown rapidly in the last five years. The USA is the most productive and influential country with 937 publications and 23,010 citations, and most of the authors and institutions with higher numbers of publications and citations are from the USA. Keyword analysis showed that breast cancer, prostate cancer, colorectal cancer, and lung cancer are the tumor types of greatest concern. Co-citation analysis showed that classification and nucleus segmentation are the main research directions of AI-based HI studies. Transfer learning and self-supervised learning in HI is on the rise. This study performed the first bibliometric analysis of AI in HI from multiple indicators, providing insights for researchers to identify key cancer types and understand the research trends of AI application in HI.


Assuntos
Neoplasias , Publicações , Inteligência Artificial , Bibliometria , Eficiência , Humanos
6.
Artigo em Inglês | MEDLINE | ID: mdl-35886713

RESUMO

Sarcopenia is characterized by progressive loss of muscle mass and function, and it is becoming a serious public health problem with the aging population. However, a comprehensive overview of the knowledge base and future trends is still lacking. The articles and reviews with "sarcopenia" in their title published from 1999 to 2021 in the SCIE database were retrieved. We used Microsoft Excel, VOSviewer, and CiteSpace to conduct a descriptive and bibliometric analysis. A total of 3582 publications were collected, from 4 published in 2000 increasing dramatically to 850 documents in 2021. The USA was the most productive country, with the most citations. The Catholic University of the Sacred Heart and Landi F were the most influential organization and author in this field, respectively. The core journal in this field was the Journal of Cachexia Sarcopenia and Muscle. According to the analysis of keywords and references, we roughly categorized the main research areas into four domains as follows: 1. Definition and diagnosis; 2. Epidemiology; 3. Etiology and pathogenesis; 4. Treatments. Comparing different diagnostic tools and the epidemiology of sarcopenia in different populations are recent hotspots, while more efforts are needed in the underlying mechanism and developing safe and effective treatments. In conclusion, this study provides comprehensive insights into developments and trends in sarcopenia research that can help researchers and clinicians better manage and implement their work.


Assuntos
Bibliometria , Publicações , Eficiência , Previsões , Bases de Conhecimento
7.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 2887-2890, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891850

RESUMO

Heart failure (HF) is a serious syndrome, with high rates of mortality. Accurate classification of HF according to the left ventricular ejection faction (EF) plays an important role in the clinical treatment. Compared to echocardiography, cine cardiac magnetic resonance images (Cine-CMR) can estimate more accurate EF, whereas rare studies focus on the application of Cine-CMR. In this paper, a self-supervised learning framework for HF classification called SSLHF was proposed to automatically classify the HF patients into HF patients with preserved EF and HF patients with reduced EF based on Cine-CMR. In order to enable the classification network better learn the spatial and temporal information contained in the Cine-CMR, the SSLHF consists of two stages: self-supervised image restoration and HF classification. In the first stage, an image restoration proxy task was designed to help a U-Net like network mine the HF information in the spatial and temporal dimensions. In the second stage, a HF classification network whose weights were initialized by the encoder part of the U-Net like network was trained to complete the HF classification. Benefitting from the proxy task, the SSLHF achieved an AUC of 0.8505 and an ACC of 0.8208 in the 5-fold cross-validation.


Assuntos
Insuficiência Cardíaca , Imagem Cinética por Ressonância Magnética , Coração , Insuficiência Cardíaca/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Aprendizado de Máquina Supervisionado
8.
Annu Int Conf IEEE Eng Med Biol Soc ; 2021: 3479-3482, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34891989

RESUMO

Metal artifact reduction (MAR) is a challenge for commercial CT systems. The metal objects of high density adversely affect the measurement process and bring difficulties to image reconstruction. Compressed sensing (CS) reconstruction algorithms have been successfully applied in MAR. Ideally, the desired anatomical information can be restored from incomplete projection data. However, in most practical cases, these conventional CS algorithms may instead introduce severe secondary artifacts due to improper prior information. In this paper, we propose a customized total variation (CTV) method to reduce the metal artifacts based on the specific pattern of the artifacts. The gradient operator within the TV norm is redefined according to the distribution of both the metal objects and tissues for each MAR case. We also provide a weighting strategy to further protect the fine details. Experimental results show that the CTV method achieves better performances than those of the conventional methods.


Assuntos
Artefatos , Procedimentos de Cirurgia Plástica , Algoritmos , Metais , Tomografia Computadorizada por Raios X
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