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381.
Vincent
(2023-06-30 15:00):
#paper https://www.nature.com/articles/s41467-018-04608-8, Nature communication 2018, Exploring patterns enriched in a dataset with contrastive principal component analysis
PCA(主成分分析)能够将高维数据映射到低维,是最常用的数据探索和可视化工具。然而PCA(以及其他降维方法例如t-sne, umap)每次只能分析一个数据集。当处理多个数据集,尤其是寻找某数据集特有的信号时,使用PCA就需要人工比较不同数据集的投影来试图寻找数据集间的相似和不同点。这篇文章提出了解决此类问题的一种简单有效的降维方法:对比PCA。该方法旨在寻找一个投影,使得目标数据集和背景数据集的差距尽可能大,从而富集目标数据集特有的信号。该方法原理与实现和PCA类似,后续实验验证了其能有效发现那些被PCA忽视的目标数据集特有的信号。除此之外,文章还详述了该方法的理论基础和几何表示,并指出其可以运用在很多PCA的使用场景中。
Abstract:
Visualization and exploration of high-dimensional data is a ubiquitous challenge across disciplines. Widely used techniques such as principal component analysis (PCA) aim to identify dominant trends in one dataset. However, …
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Visualization and exploration of high-dimensional data is a ubiquitous challenge across disciplines. Widely used techniques such as principal component analysis (PCA) aim to identify dominant trends in one dataset. However, in many settings we have datasets collected under different conditions, e.g., a treatment and a control experiment, and we are interested in visualizing and exploring patterns that are specific to one dataset. This paper proposes a method, contrastive principal component analysis (cPCA), which identifies low-dimensional structures that are enriched in a dataset relative to comparison data. In a wide variety of experiments, we demonstrate that cPCA with a background dataset enables us to visualize dataset-specific patterns missed by PCA and other standard methods. We further provide a geometric interpretation of cPCA and strong mathematical guarantees. An implementation of cPCA is publicly available, and can be used for exploratory data analysis in many applications where PCA is currently used.
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382.
庞庞
(2023-06-30 13:59):
#paper Performing group-level functional image analyses based on homologous functional regions mapped in individuals https://doi.org/10.1371/journal.pbio.2007032 大脑功能区域的大小、形状、位置和连接模式在个体之间可能存在巨大差异。 虽然功能组织的个体间差异已得到广泛认可,但迄今为止,功能神经影像研究的标准程序仍然依赖于将不同受试者的数据与基于整体大脑形态的名义“平均”大脑进行对齐。 研究者开发了一种方法来可靠地识别每个个体的同源功能区域,并证明基于这些同源功能区域对齐数据可以显着改善静息状态功能连接、任务功能磁共振成像激活和大脑行为关联的研究。 此外,我们发现大脑功能区域的大小、位置和连接性方面的个体差异是可分离的。
Abstract:
Functional MRI (fMRI) studies have traditionally relied on intersubject normalization based on global brain morphology, which cannot establish proper functional correspondence between subjects due to substantial intersubject variability in functional …
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Functional MRI (fMRI) studies have traditionally relied on intersubject normalization based on global brain morphology, which cannot establish proper functional correspondence between subjects due to substantial intersubject variability in functional organization. Here, we reliably identified a set of discrete, homologous functional regions in individuals to improve intersubject alignment of fMRI data. These functional regions demonstrated marked intersubject variability in size, position, and connectivity. We found that previously reported intersubject variability in functional connectivity maps could be partially explained by variability in size and position of the functional regions. Importantly, individual differences in network topography are associated with individual differences in task-evoked activations, suggesting that these individually specified regions may serve as the "localizer" to improve the alignment of task-fMRI data. We demonstrated that aligning task-fMRI data using the regions derived from resting state fMRI may lead to increased statistical power of task-fMRI analyses. In addition, resting state functional connectivity among these homologous regions is able to capture the idiosyncrasies of subjects and better predict fluid intelligence (gF) than connectivity measures derived from group-level brain atlases. Critically, we showed that not only the connectivity but also the size and position of functional regions are related to human behavior. Collectively, these findings suggest that identifying homologous functional regions across individuals can benefit a wide range of studies in the investigation of connectivity, task activation, and brain-behavior associations.
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383.
姗姗来迟
(2023-06-30 13:25):
#paper Arabic Dialect Identification with a Few Labeled Examples Using Generative Adversarial Networks
https://aclanthology.org/2022.aacl-main.16.pdf
考虑到在处理阿拉伯方言(DA)变化时引入的挑战和复杂性,基于Transformer的模型,例如BERT,在处理DA识别任务方面优于其他模型。然而,要对这些模型进行微调,需要大量的语料库。为一些阿拉伯语方言课程获取大量高质量的示例是具有挑战性和耗时的。
该论文扩展了基于Transformer的模型(ARBERT和MARBERT)使用 半监督生成对抗网络(SS-GAN)在生成对抗设置中使用未分类数据。模型能够为阿拉伯语方言样本 生成高质量的嵌入,并帮助模型更好地泛化下游分类任务。
ACL Anthology,
2022.
Abstract:
Given the challenges and complexities introduced while dealing with Dialect Arabic (DA) variations, Transformer based models, e.g., BERT, outperformed other models in dealing with the DA identification task. However, to …
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Given the challenges and complexities introduced while dealing with Dialect Arabic (DA) variations, Transformer based models, e.g., BERT, outperformed other models in dealing with the DA identification task. However, to fine-tune these models, a large corpus is required. Getting a large number high quality labeled examples for some Dialect Arabic classes is challenging and time-consuming. In this paper, we address the Dialect Arabic Identification task. We extend the transformer-based models, ARBERT and MARBERT, with unlabeled data in a generative adversarial setting using Semi-Supervised Generative Adversarial Networks (SS-GAN). Our model enabled producing high-quality embeddings for the Dialect Arabic examples and aided the model to better generalize for the downstream classification task given few labeled examples. Experimental results showed that our model reached better performance and faster convergence when only a few labeled examples are available.
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384.
Spring
(2023-06-30 13:17):
#paper Parabacteroides distasonis uses dietary inulin to suppress NASH via its metabolite pentadecanoic acid
doi: 10.1038/s41564-023-01418-7
① 小鼠模型中,菊粉比纤维素能更有效地抑制非酒精性脂肪肝炎(NASH)进展;② 用稳定同位素探测法(13C标记的菊粉)结合宏基因组测序和代谢组分析,发现菊粉可改变肠道菌群(富集潜在有益菌、抑制潜在致病菌)并可被特定肠菌吸收,其中被菊粉富集的狄氏副拟杆菌(Pd)可活跃地利用菊粉生成脂肪酸十五烷酸;③ 菊粉、Pd或十五烷酸可恢复NASH小鼠模型的肠道屏障功能,从而减少血清脂多糖和肝脏促炎细胞因子表达,对NASH发挥保护作用。
Abstract:
Non-alcoholic steatohepatitis (NASH) is the severe form of non-alcoholic fatty liver disease, and is characterized by liver inflammation and fat accumulation. Dietary interventions, such as fibre, have been shown to …
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Non-alcoholic steatohepatitis (NASH) is the severe form of non-alcoholic fatty liver disease, and is characterized by liver inflammation and fat accumulation. Dietary interventions, such as fibre, have been shown to alleviate this metabolic disorder in mice via the gut microbiota. Here, we investigated the mechanistic role of the gut microbiota in ameliorating NASH via dietary fibre in mice. Soluble fibre inulin was found to be more effective than insoluble fibre cellulose to suppress NASH progression in mice, as shown by reduced hepatic steatosis, necro-inflammation, ballooning and fibrosis. We employed stable isotope probing to trace the incorporation of C-inulin into gut bacterial genomes and metabolites during NASH progression. Shotgun metagenome sequencing revealed that the commensal Parabacteroides distasonis was enriched by C-inulin. Integration of C-inulin metagenomes and metabolomes suggested that P. distasonis used inulin to produce pentadecanoic acid, an odd-chain fatty acid, which was confirmed in vitro and in germ-free mice. P. distasonis or pentadecanoic acid was protective against NASH in mice. Mechanistically, inulin, P. distasonis or pentadecanoic acid restored gut barrier function in NASH models, which reduced serum lipopolysaccharide and liver pro-inflammatory cytokine expression. Overall this shows that gut microbiota members can use dietary fibre to generate beneficial metabolites to suppress metabolic disease.
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385.
张浩彬
(2023-06-30 11:45):
#paper The Capacity and Robustness Trade-off: Revisiting the Channel Independent Strategy for Multivariate Time Series Forecasting doi:
https://doi.org/10.48550/arXiv.2304.05206Focus to learn more
专门研究了针对多元时间序列的预测问题,探讨了使用独立预测以及联合预测的差异,证明了由于分布偏移的存在,独立预测的方法更好,应为其更加有利于缓解分布偏移的问题,提高模型的繁华性。并且文章证明了独立预测和联合预测,是一种模型容量和模型鲁棒性的权衡。随州论文提出了包括正则化,低秩分解、采用MAE代替MSE,调整序列长度等方法提高联合预测的精度
arXiv,
2023.
DOI: 10.48550/arXiv.2304.05206
Abstract:
Multivariate time series data comprises various channels of variables. The multivariate forecasting models need to capture the relationship between the channels to accurately predict future values. However, recently, there has …
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Multivariate time series data comprises various channels of variables. The multivariate forecasting models need to capture the relationship between the channels to accurately predict future values. However, recently, there has been an emergence of methods that employ the Channel Independent (CI) strategy. These methods view multivariate time series data as separate univariate time series and disregard the correlation between channels. Surprisingly, our empirical results have shown that models trained with the CI strategy outperform those trained with the Channel Dependent (CD) strategy, usually by a significant margin. Nevertheless, the reasons behind this phenomenon have not yet been thoroughly explored in the literature. This paper provides comprehensive empirical and theoretical analyses of the characteristics of multivariate time series datasets and the CI/CD strategy. Our results conclude that the CD approach has higher capacity but often lacks robustness to accurately predict distributionally drifted time series. In contrast, the CI approach trades capacity for robust prediction. Practical measures inspired by these analyses are proposed to address the capacity and robustness dilemma, including a modified CD method called Predict Residuals with Regularization (PRReg) that can surpass the CI strategy. We hope our findings can raise awareness among researchers about the characteristics of multivariate time series and inspire the construction of better forecasting models.
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386.
李翛然
(2023-06-27 14:00):
#paper Reduced hepatocyte mitophagy is an early feature of NAFLD pathogenesis and hastens the onset of steatosis, inflammation and fibrosis doi: 10.21203/rs.3.rs-2469234/v1. 这个文章很有意思。非酒精性脂肪性肝病(NAFLD)是一种全球流行性慢性疾病,是由肝细胞中肝脏脂肪过度堆积导致,因此也称为肝脏脂肪变性。临床范围包括,包括肝脂肪变性(NAFL,超过5%的肝细胞中脂肪堆积)、非酒精性脂肪性肝炎(NASH,其特征是存在肝细胞损伤、纤维化炎症等)、肝硬化和肝细胞癌。NAFLD与代谢综合征的特征密切相关,包括肥胖、胰岛素抵抗、高血糖、2型糖尿病和血脂异常。 现在基本上 35岁以上,有轻度的高血脂的人群或多或少都会出现脂肪肝。
传统的认为 脂肪肝都是吃的和代谢的问题,但是随着我们自己团队对于衰老模型的认识逐渐加深,以及各方的了解,其实非细菌性引起的各项炎症,也是引发癌症,NASH这种隐性疾病的元凶。 这一点和中医不谋而合,特别想中医上说的湿气重。 其实就是体内炎症无法清除干净的问题。
这两年真的是生物的好时候来了啊!生物信息学越来越多的应用,最终返璞归真,期待着采用天然产物来控制疾病到来的那一天。
Abstract:
Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of pathologies that includes steatosis, steatohepatitis (NASH) and fibrosis and is strongly associated with insulin resistance and type 2 diabetes. Changes in …
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Nonalcoholic fatty liver disease (NAFLD) encompasses a spectrum of pathologies that includes steatosis, steatohepatitis (NASH) and fibrosis and is strongly associated with insulin resistance and type 2 diabetes. Changes in mitochondrial function are implicated in the pathogenesis of NAFLD, particularly in the transition from steatosis to NASH. Mitophagy is a mitochondrial quality control mechanism that allows for the selective removal of damaged mitochondria from the cell via the autophagy pathway. While past work demonstrated a negative association between liver fat content and rates of mitophagy, when changes in mitophagy occur during the pathogenesis of NAFLD and whether such changes contribute to the primary endpoints associated with the disease are currently poorly defined. We therefore undertook the studies described here to establish when alterations in mitophagy occur during the pathogenesis of NAFLD, as well as to determine the effects of genetic inhibition of mitophagy via conditional deletion of a key mitophagy regulator, PARKIN, on the development of steatosis, insulin resistance, inflammation and fibrosis. We find that loss of mitophagy occurs early in the pathogenesis of NAFLD and that loss of PARKIN hastens the onset but not severity of key NAFLD disease features. These observations suggest that loss of mitochondrial quality control in response to nutritional stress may contribute to mitochondrial dysfunction and the pathogenesis of NAFLD.
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387.
符毓 Yu
(2023-06-26 23:22):
#paper doi:10.1038/171737a0 Nature, 2014, Passive radiative cooling below ambient air temperature under direct sunlight。辐射制冷材料通过反射包括紫外线、可视光、近红外和中红外等让物体温度低于环境温度。本文通过7层材料构成的冷却材料,首次在日间成功实现辐射制冷。在850W/平方米的日照下实现4.9度的降温
Abstract:
No abstract available.
388.
DeDe宝
(2023-06-25 23:08):
#paper doi https://doi.org/10.1038/s41467-023-35967-6,Nature Communications,2023, Goal-oriented representations in the human hippocampus during planning and navigation.在之前的研究中,海马被认为与长时记忆、位置表征相关,然而,最近认知和系统神经科学的研究表明,海马可能通过形成认知地图支持计划、想象和导航。在本研究中,研究者探究人类在目标导向导航任务期间的海马活动模式,以研究如何将上下文和目标纳入导航计划的构建和执行中。在计划阶段,相同背景和目标的路线之间的海马模式相似性增强。在导航阶段,海马前瞻性激活。
Abstract:
Recent work in cognitive and systems neuroscience has suggested that the hippocampus might support planning, imagination, and navigation by forming cognitive maps that capture the abstract structure of physical spaces, …
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Recent work in cognitive and systems neuroscience has suggested that the hippocampus might support planning, imagination, and navigation by forming cognitive maps that capture the abstract structure of physical spaces, tasks, and situations. Navigation involves disambiguating similar contexts, and the planning and execution of a sequence of decisions to reach a goal. Here, we examine hippocampal activity patterns in humans during a goal-directed navigation task to investigate how contextual and goal information are incorporated in the construction and execution of navigational plans. During planning, hippocampal pattern similarity is enhanced across routes that share a context and a goal. During navigation, we observe prospective activation in the hippocampus that reflects the retrieval of pattern information related to a key-decision point. These results suggest that, rather than simply representing overlapping associations or state transitions, hippocampal activity patterns are shaped by context and goals.
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389.
惊鸿
(2023-06-25 16:56):
#paper https://doi.org/10.1021/acssynbio.3c00216 Immortalized Bovine Satellite Cells for Cultured Meat Applications 为了使培养肉大规模成功,来自食品相关物种的肌肉细胞必须以快速可靠的方式在体外扩增,以每年产生数百万公吨的生物质。为了实现这一目标,遗传永生化细胞比原代细胞具有实质性的好处,包括快速生长、逃离细胞衰老以及一致的起始细胞群进行生产。在这里,我们通过牛端粒酶逆转录酶(TERT)和细胞周期蛋白依赖性激酶4(CDK4)的组成表达开发遗传永生化的牛卫星细胞(iBSC)。这些细胞在发表时实现了超过120倍的倍增,并保持其肌源分化的能力。因此,它们为该领域提供了有价值的工具,使进一步的研究和开发能够推进培养肉。
Abstract:
For cultured meat to succeed at scale, muscle cells from food-relevant species must be expanded in vitro in a rapid and reliable manner to produce millions of metric tons of …
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For cultured meat to succeed at scale, muscle cells from food-relevant species must be expanded in vitro in a rapid and reliable manner to produce millions of metric tons of biomass annually. Toward this goal, genetically immortalized cells offer substantial benefits over primary cells, including rapid growth, escape from cellular senescence, and consistent starting cell populations for production. Here, we develop genetically immortalized bovine satellite cells (iBSCs) via constitutive expression of bovine Telomerase reverse transcriptase (TERT) and Cyclin-dependent kinase 4 (CDK4). These cells achieve over 120 doublings at the time of publication and maintain their capacity for myogenic differentiation. They therefore offer a valuable tool to the field, enabling further research and development to advance cultured meat.
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390.
徐炳祥
(2023-06-25 09:39):
#paper doi:10.1186/s13059-023-02970-5 Genome Biology, 2023, Genomic and epigenomic determinants of heat stress‑induced transcriptional memory in Arabidopsis。热刺激是植物细胞经常面临的环境压力,能引起细胞内大规模转录响应。热刺激诱导的转录记忆是其中重要的调控模式,然而其形成机制尚不清楚。本文结合前后两次热刺激后的HSFA2和HSFA3结合位点、H3K4me3信号分布、ATAC-seq标记的染色质开放性和基因表达谱数据,从表观遗传层面对该问题进行了探讨。结果显示具有热刺激诱导记忆行为的基因有特征性的热刺激因子结合模式、在常温下有低表达水平但有开放的启动子区域,刺激后富集H3K4me3信号等特征。本文为刺激反应的表观遗传研究提供了一个可供借鉴的范式。
Abstract:
BACKGROUND: Transcriptional regulation is a key aspect of environmental stress responses. Heat stress induces transcriptional memory, i.e., sustained induction or enhanced re-induction of transcription, that allows plants to respond more …
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BACKGROUND: Transcriptional regulation is a key aspect of environmental stress responses. Heat stress induces transcriptional memory, i.e., sustained induction or enhanced re-induction of transcription, that allows plants to respond more efficiently to a recurrent HS. In light of more frequent temperature extremes due to climate change, improving heat tolerance in crop plants is an important breeding goal. However, not all heat stress-inducible genes show transcriptional memory, and it is unclear what distinguishes memory from non-memory genes. To address this issue and understand the genome and epigenome architecture of transcriptional memory after heat stress, we identify the global target genes of two key memory heat shock transcription factors, HSFA2 and HSFA3, using time course ChIP-seq.RESULTS: HSFA2 and HSFA3 show near identical binding patterns. In vitro and in vivo binding strength is highly correlated, indicating the importance of DNA sequence elements. In particular, genes with transcriptional memory are strongly enriched for a tripartite heat shock element, and are hallmarked by several features: low expression levels in the absence of heat stress, accessible chromatin environment, and heat stress-induced enrichment of H3K4 trimethylation. These results are confirmed by an orthogonal transcriptomic data set using both de novo clustering and an established definition of memory genes.CONCLUSIONS: Our findings provide an integrated view of HSF-dependent transcriptional memory and shed light on its sequence and chromatin determinants, enabling the prediction and engineering of genes with transcriptional memory behavior.
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391.
龙海晨
(2023-06-25 00:06):
#paper Haichen Long, Yangyang Li, Huijuan Wang, Bingxuan Guo, Shuyan Song, Xiangyi Zhe, Hongtao Li, Dongmei Li, Renfu Shao, Zemin Pan . C/EBPβ expression decreases in cervical cancer and leads to tumorigenesis. BMC Cancer. 2023 Jan 24;23(1):79. doi: 10.1186/s12885-023-10543-9. PMID: 36694148; PMCID: PMC9872280. 这是我第一次作为第一作者在中科院Top期刊上发的文章,也是2023年发的第二篇文章。是群里分享的第三篇我作为作者的文章。目的是研究C/EBPβ蛋白在宫颈肿瘤发生和发展中的作用。整个过程中,我们采用定量RT-PCR分析临床标本(10例宫颈癌组织标本和10例相应正常宫颈组织标本)中C/EBPβ、miR-661和MTA1 mRNA的表达。应用免疫组织化学方法分析381例临床标本C/EBPβ、80例临床标本Ki67和60例临床标本PCNA蛋白的表达。采用MALDI-TOF MassARRAY分析C/EBPβ基因甲基化(13例宫颈癌症组织和13例相应的正常宫颈组织)。采用CCK-8分析宫颈癌症细胞系的细胞增殖情况。采用蛋白质印迹和免疫组织化学方法检测C/EBPβ蛋白的表达水平,并用定量RT-PCR分析mRNA的表达。采用流式细胞术检测细胞周期分布和细胞凋亡。进行集落形成、Transwell、细胞侵袭和伤口愈合测定以检测细胞迁移和侵袭。
通过实验,我们证明了,C/EBPβ在宫颈癌症组织中降低,C/EBP-β基因在宫颈癌症细胞中的过度表达可以抑制增殖、侵袭和迁移。
Abstract:
BACKGROUND: Cervical cancer is currently estimated to be the fourth most common cancer among women worldwide and the leading cause of cancer-related deaths in some of the world's poorest countries. …
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BACKGROUND: Cervical cancer is currently estimated to be the fourth most common cancer among women worldwide and the leading cause of cancer-related deaths in some of the world's poorest countries. C/EBPβ has tumor suppressor effects because it is necessary for oncogene-induced senescence. However, C/EBPβ also has an oncogenic role. The specific role of C/EBPβ in cervical cancer as a tumor suppressor or oncoprotein is unclear.OBJECTIVE: To explore the role of the C/EBPβ protein in cervical tumorigenesis and progression.METHODS: Quantitative RT-PCR was used to analyze C/EBPβ (15 cervical cancer tissue samples and 15 corresponding normal cervical tissue samples), miR-661, and MTA1 mRNA expression in clinical samples (10 cervical cancer tissue samples and 10 corresponding normal cervical tissue samples). Immunohistochemistry was used to analyze C/EBPβ (381 clinical samples), Ki67 (80 clinical samples) and PCNA ( 60 clinical samples) protein expression. MALDI-TOF MassARRAY was used to analyze C/EBPβ gene methylation (13 cervical cancer tissues and 13 corresponding normal cervical tissues). Cell proliferation was analyzed by CCK-8 in cervical cancer cell lines. Western blotting and immunohistochemistry were performed to detect C/EBPβ protein expression levels, and mRNA expression was analyzed by quantitative RT-PCR analysis. Flow cytometry was performed to measure cell cycle distribution and cell apoptosis. Colony formation, Transwell, cell invasion, and wound healing assays were performed to detect cell migration and invasion.RESULTS: C/EBPβ protein expression was significantly reduced in cervical cancer tissues compared with cervicitis tissues (P < 0.01). Ki67 protein and PCNA protein expression levels were significantly higher in cervical cancer tissues compared with cervicitis tissues. The rate of C/EBPβ gene promoter methylation of CpG12, 13, 14 and CpG19 in cervical cancer tissues was significantly increased compared with normal cervical tissue (P < 0.05). In addition, C/EBPβ was overexpressed in cervical cancer cells and this overexpression inhibited cell proliferation, migration, invasion, arrested cells in S phase, and promoted apoptosis.CONCLUSIONS: We have demonstrated that C/EBPβ decreased in cervical cancer tissues and overexpression of the C/EBPβ gene in cervical cancer cells could inhibit proliferation, invasion and migration.
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392.
龙海晨
(2023-06-24 23:55):
#paper Weinan Zheng, Fuyuan Jin, Fang Wang, Luyue Wang, Shaowei Fu, Zemin Pan, Haichen Long. Analysis of eEF1A2 gene expression and copy number in cervical carcinoma. Medicine (Baltimore). 2023 Jan 13;102(2):e32559. doi: 10.1097/MD.0000000000032559. PMID: 36637958; PMCID: PMC9839279. 这是我第一次作为独立通讯作者发的文章也是2023年发的第一篇文章。是群里分享的第二篇我作为作者的文章。因为是阴性结果,没有发到太好的杂志。杂志要求补实验数据时,赶上疫情,封在家里,所以用生物信息学补的。这是一篇分子生物学和生物信息学相结合的文章。主要研究eEF1A2基因拷贝数与宫颈癌患者临床分期、病理分级和患者生存率之间的关系。QPCR分析样本拷贝数。生物信息学数据库分析相关数据。发现,eEF1A2基因在癌症组织中发生突变。eEF1A2基因拷贝数与子宫颈癌症组织中eEF1A1基因表达的变化无关。
Abstract:
OBJECTIVE: To explore and analyze the expression of eukaryotic translation elongation factor 1 alpha 2 (eEF1A2) gene in cervical cancer tissues, its relationship with patient survival, gene mutations, and changes …
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OBJECTIVE: To explore and analyze the expression of eukaryotic translation elongation factor 1 alpha 2 (eEF1A2) gene in cervical cancer tissues, its relationship with patient survival, gene mutations, and changes in copy number in cervical cancer and chronic cervicitis tissues.METHODS: The expression of the eEF1A2 gene in cervical cancer and its relationship with patient survival were analyzed using gene expression profile interactive analysis. Changes in eEF1A2 expression in cervical cancer tissues were analyzed using cBioPortal, a portal for cancer genomics analysis. The eEF1A2 copy number in cervical cancer tissues and chronic cervicitis tissues was determined by real-time fluorescence quantitative polymerase chain reaction. The relationship between the expression of eEF1A2 protein and the clinical stage, pathological grade, and patient survival of cervical cancer was analyzed by the database: The Human Protein Atlas, an integrated repository portal for tumor-immune system interactions.RESULTS: Gene expression profile interactive analysis database analysis showed no significant differences in the expression of eEF1A2 between cervical cancer and normal cervical tissues (P > .05). The eEF1A2 gene expression level was not correlated with the survival of cervical cancer patients (P > .05). Analysis of the cBioPortal database showed that 18 of 297 cervical cancer patients had eEF1A2 gene changes, including missense mutation, splice mutation, amplification, and messenger RNA increase. There was no significant difference in eEF1A2 gene copy number between cervical cancer and chronic cervicitis (P > .05). The Human Protein Atlas and an integrated repository portal for tumor-immune system interactions database analysis of immunohistochemical data showed that eEF1A2 protein expression was no significant difference in clinical stage, pathological grade and patient survival of cervical cancer (P > .05).CONCLUSION: The eEF1A2 gene was mutated in cervical cancer tissues. The eEF1A2 gene copy number was not associated with changes in the expression of the eEF1A2 gene in cervical cancer tissues.
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393.
颜林林
(2023-06-24 21:59):
#paper doi:10.1093/nar/gkad526 Nucleic Acids Research, 2023, Precise characterization of somatic complex structural variations from tumor/control paired long-read sequencing data with nanomonsv. 这是一篇生信文章,作者开发了一个工具nanomonsv,基于配对的肿瘤和对照样本的三代测序数据,鉴定构变异(SV)。该程序包括两个模块:Canonical SV module 和 Single breakend SV module,前者采取寻找跨越断点的多条支持reads的策略,后者则先对断点单侧的序列进行合并,再通过soft clip部分去寻找(可能在基因组上缺失或难以判定)的另一侧序列。通过对这两种策略的实现、优化和整合,提高了对SV的鉴定性能。本文在三个肿瘤细胞系样本(及其对应对照样本)的三代数据上,对所开发的工具进行了实测和评估,并使用PCR方法对部分结果进行了验证。此外,本文还对甲基化、重复序列、移动元件、病毒序列整合等序列特性进行了分析,以进一步充实文章的内容。
Abstract:
We present our novel software, nanomonsv, for detecting somatic structural variations (SVs) using tumor and matched control long-read sequencing data with a single-base resolution. The current version of nanomonsv includes …
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We present our novel software, nanomonsv, for detecting somatic structural variations (SVs) using tumor and matched control long-read sequencing data with a single-base resolution. The current version of nanomonsv includes two detection modules, Canonical SV module, and Single breakend SV module. Using tumor/control paired long-read sequencing data from three cancer and their matched lymphoblastoid lines, we demonstrate that Canonical SV module can identify somatic SVs that can be captured by short-read technologies with higher precision and recall than existing methods. In addition, we have developed a workflow to classify mobile element insertions while elucidating their in-depth properties, such as 5' truncations, internal inversions, as well as source sites for 3' transductions. Furthermore, Single breakend SV module enables the detection of complex SVs that can only be identified by long-reads, such as SVs involving highly-repetitive centromeric sequences, and LINE1- and virus-mediated rearrangements. In summary, our approaches applied to cancer long-read sequencing data can reveal various features of somatic SVs and will lead to a better understanding of mutational processes and functional consequences of somatic SVs.
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394.
小W
(2023-05-31 23:59):
#paper doi:https://doi.org/10.1016/j.cell.2023.03.035
Massively parallel base editing to map variant effects in human hematopoiesis 本文介绍了一种基因编辑工具:碱基编辑器,在原代人类造血干细胞进行研究的文章。通过结合碱基编辑器和单细胞rna 测序技术,进行了以下研究:对人类全基因组关联研究发现的大量单核苷酸变异的实验评估,对患者临床测序鉴定突变的致病性评估。
Abstract:
Systematic evaluation of the impact of genetic variants is critical for the study and treatment of human physiology and disease. While specific mutations can be introduced by genome engineering, we …
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Systematic evaluation of the impact of genetic variants is critical for the study and treatment of human physiology and disease. While specific mutations can be introduced by genome engineering, we still lack scalable approaches that are applicable to the important setting of primary cells, such as blood and immune cells. Here, we describe the development of massively parallel base-editing screens in human hematopoietic stem and progenitor cells. Such approaches enable functional screens for variant effects across any hematopoietic differentiation state. Moreover, they allow for rich phenotyping through single-cell RNA sequencing readouts and separately for characterization of editing outcomes through pooled single-cell genotyping. We efficiently design improved leukemia immunotherapy approaches, comprehensively identify non-coding variants modulating fetal hemoglobin expression, define mechanisms regulating hematopoietic differentiation, and probe the pathogenicity of uncharacterized disease-associated variants. These strategies will advance effective and high-throughput variant-to-function mapping in human hematopoiesis to identify the causes of diverse diseases.
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395.
Ricardo
(2023-05-31 23:53):
#paper DOI:https://doi.org/10.48550/arXiv.2304.00217 DrDisco: Deep Registration for Distortion Correction of Diffusion MRI with single phase-encoding 弥散加权磁共振成像(DW-MRI)是一种对人脑白质束进行无创成像的方法。dw - mri通常采用高梯度回波平面成像(echo-planar imaging, EPI)获得,会引入严重的几何畸变,影响进一步的分析。大多数校正失真的工具需要两张不同相位编码方向获取的最小加权DW-MRI图像(B0),处理每个受试者可能需要数小时。由于大量扩散数据仅在单一相位编码方向下获取,现有方法的应用受到限制。本文提出一种基于深度学习的配准方法,仅使用从单一相位编码方向获得的B0来纠正失真。通过一个深度学习模型,将未失真的t1加权图像与失真的B0图像进行配准,以消除失真。在训练过程中应用可微的互信息损失来改善模态间对齐。在Human Connectome Project数据集上的实验表明,所提出的方法在多个指标上优于SyN和VoxelMorph,且处理一个受试者只需几秒钟。
arXiv,
2023.
DOI: 10.48550/arXiv.2304.00217
Abstract:
Diffusion-weighted magnetic resonance imaging (DW-MRI) is a non-invasive way of imaging white matter tracts in the human brain. DW-MRIs are usually acquired using echo-planar imaging (EPI) with high gradient fields, …
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Diffusion-weighted magnetic resonance imaging (DW-MRI) is a non-invasive way of imaging white matter tracts in the human brain. DW-MRIs are usually acquired using echo-planar imaging (EPI) with high gradient fields, which could introduce severe geometric distortions that interfere with further analyses. Most tools for correcting distortion require two minimally weighted DW-MRI images (B0) acquired with different phase-encoding directions, and they can take hours to process per subject. Since a great amount of diffusion data are only acquired with a single phase-encoding direction, the application of existing approaches is limited. We propose a deep learning-based registration approach to correct distortion using only the B0 acquired from a single phase-encoding direction. Specifically, we register undistorted T1-weighted images and distorted B0 to remove the distortion through a deep learning model. We apply a differentiable mutual information loss during training to improve inter-modality alignment. Experiments on the Human Connectome Project dataset show the proposed method outperforms SyN and VoxelMorph on several metrics, and only takes a few seconds to process one subject.
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396.
笑对人生
(2023-05-31 23:47):
#paper doi: 10.1038/s41467-023-36948-5. Yang B, et al. CTCF controls three-dimensional enhancer network underlying the inflammatory response of bone marrow-derived dendritic cells. Nat Commun. 2023 Mar 8;14(1):1277.
树突状细胞是一类重要的抗原呈递细胞,参与先天性和适应性免疫的精密调控过程。激活的树突状细胞能够通过上调主要相容性复合物、共刺激分子和多种促炎细胞因子调节淋巴细胞的激活和分化。然而,树突状细胞的异常激活可能会导致多发硬化等自身免疫性疾病。因此,深入研究树突状细胞激活的内在机制对相关疾病治疗策略的制定具有重要意义。本研究结合HiC、ChIP-seq和RNAseq三种组学技术,在三维基因组层面揭示了骨髓来源的树突状细胞激活重要机制。研究结果显示,染色质loop结构和增强子-启动子互作重编程诱导树突状细胞激活;树突状细胞CTCF缺失后会引起粒细胞-巨噬细胞集落刺激因子(GM-CSF)介导的JAK2/STAT5信号通路,最终导致NF-kB复合物失活;CTCF是NK-kB依赖染色质互作和增强与Th1和Th17细胞分化相关的促炎细胞因子表达的关键分子。
Abstract:
Dendritic cells are antigen-presenting cells orchestrating innate and adaptive immunity. The crucial role of transcription factors and histone modifications in the transcriptional regulation of dendritic cells has been extensively studied. …
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Dendritic cells are antigen-presenting cells orchestrating innate and adaptive immunity. The crucial role of transcription factors and histone modifications in the transcriptional regulation of dendritic cells has been extensively studied. However, it is not been well understood whether and how three-dimensional chromatin folding controls gene expression in dendritic cells. Here we demonstrate that activation of bone marrow-derived dendritic cells induces extensive reprogramming of chromatin looping as well as enhancer activity, both of which are implicated in the dynamic changes in gene expression. Interestingly, depletion of CTCF attenuates GM-CSF-mediated JAK2/STAT5 signaling, resulting in defective NF-κB activation. Moreover, CTCF is necessary for establishing NF-κB-dependent chromatin interactions and maximal expression of pro-inflammatory cytokines, which prime Th1 and Th17 cell differentiation. Collectively, our study provides mechanistic insights into how three-dimensional enhancer networks control gene expression during bone marrow-derived dendritic cells activation, and offers an integrative view of the complex activities of CTCF in the inflammatory response of bone marrow-derived dendritic cells.
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397.
半面阳光
(2023-05-31 23:32):
#paper DOI: 10.12688/wellcomeopenres.10069.1,Wellcome Open Res, 2016, Accurate clinical detection of exon copy number variants in a targeted NGS panel using DECoN, 一篇方法学文章,作者开发了一个用于准确检出外显子测序数据中的CNVs的工具-DECoN。同时采用近2000个样本对DECoN的性能进行了验证和评估。WES测序在临床诊断的应用逐渐广泛,这篇文章中的工具为充分利用WES数据提供了一种可能。
Abstract:
Targeted next generation sequencing (NGS) panels are increasingly being used in clinical genomics to increase capacity, throughput and affordability of gene testing. Identifying whole exon deletions or duplications (termed exon …
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Targeted next generation sequencing (NGS) panels are increasingly being used in clinical genomics to increase capacity, throughput and affordability of gene testing. Identifying whole exon deletions or duplications (termed exon copy number variants, 'exon CNVs') in exon-targeted NGS panels has proved challenging, particularly for single exon CNVs. We developed a tool for the Detection of Exon Copy Number variants (DECoN), which is optimised for analysis of exon-targeted NGS panels in the clinical setting. We evaluated DECoN performance using 96 samples with independently validated exon CNV data. We performed simulations to evaluate DECoN detection performance of single exon CNVs and to evaluate performance using different coverage levels and sample numbers. Finally, we implemented DECoN in a clinical laboratory that tests and with the TruSight Cancer Panel (TSCP). We used DECoN to analyse 1,919 samples, validating exon CNV detections by multiplex ligation-dependent probe amplification (MLPA). In the evaluation set, DECoN achieved 100% sensitivity and 99% specificity for BRCA exon CNVs, including identification of 8 single exon CNVs. DECoN also identified 14/15 exon CNVs in 8 other genes. Simulations of all possible BRCA single exon CNVs gave a mean sensitivity of 98% for deletions and 95% for duplications. DECoN performance remained excellent with different levels of coverage and sample numbers; sensitivity and specificity was >98% with the typical NGS run parameters. In the clinical pipeline, DECoN automatically analyses pools of 48 samples at a time, taking 24 minutes per pool, on average. DECoN detected 24 BRCA exon CNVs, of which 23 were confirmed by MLPA, giving a false discovery rate of 4%. Specificity was 99.7%. DECoN is a fast, accurate, exon CNV detection tool readily implementable in research and clinical NGS pipelines. It has high sensitivity and specificity and acceptable false discovery rate. DECoN is freely available at www.icr.ac.uk/decon.
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398.
小擎子
(2023-05-31 23:05):
#paper 10.1126/science.1257481 Science, 2014 , High thermodynamic stability of parametrically designed helical bundles 参数化设计的螺旋束的高热力学稳定性。通过参数化骨架生成与Rosetta蛋白质设计相结合的方法,生成非常稳定的蛋白质结构。不依赖已知序列基序的情况下轻松生成具有精细几何形状的超稳定蛋白质,有助于基于蛋白质的纳米结构、疗法和催化剂的设计。核心是参数化设计,依靠的是对Crick Coiled-coil方程做参数扰动。0.1埃的扰动可以生成成千上万个α螺旋设计骨架。文章找了几种低能量的设计做测试,实验验证,晶体结构与设计一致,且稳定性超好,堪称“砖头”。ps 因文章较早,用的是Rosetta设计序列,如果改用ProteinMPNN,可以生成有更多活性表达的蛋白质序列。
Abstract:
We describe a procedure for designing proteins with backbones produced by varying the parameters in the Crick coiled coil-generating equations. Combinatorial design calculations identify low-energy sequences for alternative helix supercoil …
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We describe a procedure for designing proteins with backbones produced by varying the parameters in the Crick coiled coil-generating equations. Combinatorial design calculations identify low-energy sequences for alternative helix supercoil arrangements, and the helices in the lowest-energy arrangements are connected by loop building. We design an antiparallel monomeric untwisted three-helix bundle with 80-residue helices, an antiparallel monomeric right-handed four-helix bundle, and a pentameric parallel left-handed five-helix bundle. The designed proteins are extremely stable (extrapolated ΔGfold > 60 kilocalories per mole), and their crystal structures are close to those of the design models with nearly identical core packing between the helices. The approach enables the custom design of hyperstable proteins with fine-tuned geometries for a wide range of applications.
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399.
林海onrush
(2023-05-31 22:41):
#paper,Mastering the Game of Stratego with Model-Free Multiagent Reinforcement Learning,DOI: 10.1126/science.add4679,强化学习在军事战略模拟领域的尝试如何?作者团队给出了一个可行的思路:如何使用无模型的多智能体强化学习来掌握战略游戏Stratego。本文提出了DeepNash,一个能够学习玩不完美信息游戏Stratego1从零开始,直至达到人类专家的水平。战略游戏是人工智能尚未掌握的少数标志性棋盘游戏之一。(AI)还没有掌握的少数标志性棋盘游戏之一。这个流行的游戏有一个巨大的游戏树10535个节点,也就是说,比围棋大0175倍。它有它还有一个额外的复杂性,就是需要在不完美的信息下进行决策。在tratego中,决策是在大量没有明显的离散行动的情况下做出的。行动和结果之间没有明显的联系。情节很长,在玩家获胜之前往往有几百步棋,而且战略游戏中的情况不容易被分解为可管理的大小的子问题。由于这些原因,几十年来《策略》一直是人工智能领域的一个巨大挑战,而现有的人工智能方法几乎没有达到业余水平。业余水平的游戏。DeepNash使用了一种游戏理论的、无模型的深度强化学习方法,不需要搜索,它通过自我游戏来学习掌握Stratego。正则化纳什动力学(R-aD)算法是DeepNash的一个关键组成部分,它收敛到一个近似的纳什均衡,通过直接修改基础的多Agent学习动态性。DeepNash击败了Stratego中现有的最先进的人工智能方法。并在Gravon游戏平台上取得了年度(2022年)和历史上前三名的成绩。平台上取得了年度(2022年)和历史上的前三名,与人类专家玩家竞争。本文的工作很有意思,有进一步探索的空间。个人认为此思路在MOBA类游戏中有很强的可拓展性。
Abstract:
We introduce DeepNash, an autonomous agent that plays the imperfect information game Stratego at a human expert level. Stratego is one of the few iconic board games that artificial intelligence …
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We introduce DeepNash, an autonomous agent that plays the imperfect information game Stratego at a human expert level. Stratego is one of the few iconic board games that artificial intelligence (AI) has not yet mastered. It is a game characterized by a twin challenge: It requires long-term strategic thinking as in chess, but it also requires dealing with imperfect information as in poker. The technique underpinning DeepNash uses a game-theoretic, model-free deep reinforcement learning method, without search, that learns to master Stratego through self-play from scratch. DeepNash beat existing state-of-the-art AI methods in Stratego and achieved a year-to-date (2022) and all-time top-three ranking on the Gravon games platform, competing with human expert players.
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400.
符毓 Yu
(2023-05-31 22:40):
#paper doi.org/10.48550/arXiv.2212.12669
Nature, 2023, On Realization of Intelligent Decision-Making in the Real World: A Foundation Decision Model Perspective。本文讨论了由于不确定性和动态环境,在现实场景中实现机器主导的智能决策(IDM)所面临的挑战。作者提出了一个基础决策模型(FDM)的想法来克服这些挑战,并使IDM得到广泛采用。本文还展示了人工智能增强IDM潜在的各种方法和理论可行性。
arXiv,
2023.
DOI: 10.48550/arXiv.2212.12669
Abstract:
The pervasive uncertainty and dynamic nature of real-world environments present significant challenges for the widespread implementation of machine-driven Intelligent Decision-Making (IDM) systems. Consequently, IDM should possess the ability to continuously …
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The pervasive uncertainty and dynamic nature of real-world environments present significant challenges for the widespread implementation of machine-driven Intelligent Decision-Making (IDM) systems. Consequently, IDM should possess the ability to continuously acquire new skills and effectively generalize across a broad range of applications. The advancement of Artificial General Intelligence (AGI) that transcends task and application boundaries is critical for enhancing IDM. Recent studies have extensively investigated the Transformer neural architecture as a foundational model for various tasks, including computer vision, natural language processing, and reinforcement learning. We propose that a Foundation Decision Model (FDM) can be developed by formulating diverse decision-making tasks as sequence decoding tasks using the Transformer architecture, offering a promising solution for expanding IDM applications in complex real-world situations. In this paper, we discuss the efficiency and generalization improvements offered by a foundation decision model for IDM and explore its potential applications in multi-agent game AI, production scheduling, and robotics tasks. Lastly, we present a case study demonstrating our FDM implementation, DigitalBrain (DB1) with 1.3 billion parameters, achieving human-level performance in 870 tasks, such as text generation, image captioning, video game playing, robotic control, and traveling salesman problems. As a foundation decision model, DB1 represents an initial step toward more autonomous and efficient real-world IDM applications.
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