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261.
笑对人生
(2023-10-31 23:59):
# paper doi: 10.1038/s41591-022-01906-z. Fu B, et al. CRISPR-Cas9-mediated gene editing of the BCL11A enhancer for pediatric β0/β0 transfusion-dependent β-thalassemia. Nat Med. 2022 Aug;28(8):1573-1580.
研究背景:B细胞淋巴瘤/白血病11A蛋白(B-cell lymphoma/leukemia 11A,BCL11A)是一种转录因子,可抑制红系细胞中的γ-珠蛋白和胎儿血红蛋白表达。因此,理论上靶向抑制BCL11A的表达可能使γ-珠蛋白表达抑制解除。地中海贫血(Thalassemia)是由于珠蛋白基因突变、缺失导致的珠蛋白链合成减少或完全缺失所引起的遗传性慢性溶血性疾病。根据临床症状严重程度和是否需要定期输血将地贫分为输血依赖型地贫(TDT)和非输血依赖型地贫(NTDT)。TDT需终身依赖输血,包括重型β地贫、重型Hb E/β地贫、非缺失型HbH病和重型α地贫。人出生后不久胎儿期γ-珠蛋白 (γ-globin)基因沉默表达,成体则主要表达β-珠蛋白 (β-globin),它在红细胞中与a-珠蛋白组成血红蛋白四聚体(HbA : α2β2)运载氧气。过去的研究表明,胎儿血红蛋白(HbF)水平升高可以减轻镰状细胞病 (SCD)和β-地中海贫血的临床严重程度,利用HbF替代功能受损的HbA可能是治疗β地贫的可行方案之一。在2020年,NEJM同期分别发表了两项分别利用CRISPR-Cas9和慢病毒介导的shRNA治疗β-地中海贫血症患者和镰刀状细胞贫血症患者临床试验。第一项是利用CRISPR-Cas9对患者自体CD34+细胞BCL11A的增强子区域(GATA1结合位点)进行编辑,激活γ-珠蛋白表达,最终提高血液中HbF含量。第二项是慢病毒介导的shRNA,在体外特异性靶向敲低患者自体CD34+细胞的BCL11A基因的mRNA。
研究内容:本研究是中国,也是世界首个通过CRISPR基因编辑技术重激活γ珠蛋白治疗β0/β0型重度地中海贫血儿童(两名TDT患者)并获得成功的研究。两名患者体内红细胞数量和总体Hb水平在75天左右达到健康水平。此外,研究还利用scRNAseq分析了两名健康人、一名患者治疗前和两名患者治疗后的PBMC,在单细胞水平验证了他们之间各种细胞类型比例均无显著差异。
Abstract:
Gene editing to disrupt the GATA1-binding site at the +58 BCL11A erythroid enhancer could induce γ-globin expression, which is a promising therapeutic strategy to alleviate β-hemoglobinopathy caused by HBB gene …
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Gene editing to disrupt the GATA1-binding site at the +58 BCL11A erythroid enhancer could induce γ-globin expression, which is a promising therapeutic strategy to alleviate β-hemoglobinopathy caused by HBB gene mutation. In the present study, we report the preliminary results of an ongoing phase 1/2 trial (NCT04211480) evaluating safety and efficacy of gene editing therapy in children with blood transfusion-dependent β-thalassemia (TDT). We transplanted BCL11A enhancer-edited, autologous, hematopoietic stem and progenitor cells into two children, one carrying the β/β genotype, classified as the most severe type of TDT. Primary endpoints included engraftment, overall survival and incidence of adverse events (AEs). Both patients were clinically well with multilineage engraftment, and all AEs to date were considered unrelated to gene editing and resolved after treatment. Secondary endpoints included achieving transfusion independence, editing rate in bone marrow cells and change in hemoglobin (Hb) concentration. Both patients achieved transfusion independence for >18 months after treatment, and their Hb increased from 8.2 and 10.8 g dl at screening to 15.0 and 14.0 g dl at the last visit, respectively, with 85.46% and 89.48% editing persistence in bone marrow cells. Exploratory analysis of single-cell transcriptome and indel patterns in edited peripheral blood mononuclear cells showed no notable side effects of the therapy.
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262.
林海onrush
(2023-10-31 23:55):
#paper,Quantum Brain Dynamics in 2 + 1 dimensions:Non-equilibrium analysis towards memory formations,https://doi.org/10.1016/j.physa.2022.127397,量子脑动力学(英语:Quantum Brain Dynamics,缩写:QBD)是神经系统科学中的一种假说,目的是在量子场论(QFT)的理论框架下解释大脑的功能。本文的研究人员通过数值模拟,描述了在 2 + 1 维量子脑动力学(QBD)中导致对称性破缺的非平衡过程。采用相干电场、偶极矩密度和偶极矩密度时间导数的时间演化方程,以及非相干偶极子和光子的Kadanoff–Baym方程。最终证明了玻色-爱因斯坦分布适用于非相干偶极子和光子的时间演化。在非零初始电场的触发下,系统的偶极子朝同一方向排列。 这些结果可以作为 QBD 中记忆形成的代表。
其实QBD早在1967年就被人们所关注和研究了,Hiroomi Umezawa 等人提出了脑细胞内部和脑细胞之间的长程相干(long range correlation) 的量子脑动力学理论,并展示了通过南部-戈德斯通玻色子(Nambu-Goldstone bosons) 来实现记忆的存储和检索的可能机制。占大脑70% 的水分子有两个电极,其中水分子的电偶极矩形 成了一个称为“皮层场”的量子场,皮层场中的量子被称为“皮层子”(corticon)。皮层场和神经细胞中的生物分子产生的量子相干波相互作用,可以在神经元和神经网络中传播。这种波在传播过程种能从ATP(三磷酸腺苷) 中获得能量,进而控制神经元的离子通道,并控制信号流向神经突触。量子大脑动力学的研究者们认为,意识并非由某种确定的途径所产生。一方面,吉布(Mari Jibu) 和雅苏(Kunio Yasue)认为,在神经网络中,皮层场和生物分子波的能量量子之间的相互作用产生了意识。另一方面,维泰罗(Giuseppe Vitiello)认为,量子脑动力学中的量子状态产生了两极,一极是主观的外部世界的表现,另一极是向外部世界表现开放的自我。QBD是一种新颖的、用于研究大脑的高级功能(如意识和记忆) 的量子框架,描述了在大脑神经活动层面上经典行为涌现的原因和方式。
263.
小W
(2023-10-31 23:52):
#paper doi:10.1016/j.stem.2023.09.014 Decoding aging-dependent regenerative decline across tissues at single-cell resolution 本文主要讲述了衰老对组织损伤修复的的影响,作者构建了小鼠的八个不同组织损伤模型,对年轻和衰老小鼠的损伤前、修复开始、修复进展和修复消退四个阶段,进行单细胞转录组分析,绘画不同年纪、损伤修复阶段和组织独特和共享的基因特征和细胞特征。本文主要的两个观点:衰老和年轻小鼠在损伤修复时激活不同 MuSC 亚型的干细胞,衰老MuSC 亚型的干细胞具有较弱的分化能力;Arg1+ 巨噬细胞在各种组织的再生和修复中激增,衰老小鼠 Arg1+ 巨噬细胞受到削弱,其可能通过影响血管生成能力,,导致衰老个体损伤修复能力的衰退。
Abstract:
Regeneration across tissues and organs exhibits significant variation throughout the body and undergoes a progressive decline with age. To decode the relationships between aging and regenerative capacity, we conducted a …
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Regeneration across tissues and organs exhibits significant variation throughout the body and undergoes a progressive decline with age. To decode the relationships between aging and regenerative capacity, we conducted a comprehensive single-cell transcriptome analysis of regeneration in eight tissues from young and aged mice. We employed diverse analytical models to study tissue regeneration and unveiled the intricate cellular and molecular mechanisms underlying the attenuated regenerative processes observed in aged tissues. Specifically, we identified compromised stem cell mobility and inadequate angiogenesis as prominent contributors to this age-associated decline in regenerative capacity. Moreover, we discovered a unique subset of Arg1 macrophages that were activated in young tissues but suppressed in aged regenerating tissues, suggesting their important role in age-related immune response disparities during regeneration. This study provides a comprehensive single-cell resource for identifying potential targets for interventions aimed at enhancing regenerative outcomes in the aging population.
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264.
半面阳光
(2023-10-31 23:28):
#paper DOI: 10.3389/fpubh.2017.00307, Frontiers in public health, 2017, Sensitivity, Specificity, and Predictive Values: Foundations, Pliabilities, and Pitfalls in Research and Practice. 在筛查类的检测中,经常会提到灵敏度、特异性和预测值等概念。本文较为详细地介绍了这几个常用概念,并指出了研究人员和临床医生会时常对这些概念产生误解或曲解。最后探讨了正确使用这些概念对医学相关的研究、临床应用、乃至受检者获益的重要性。
Abstract:
Within the context of screening tests, it is important to avoid misconceptions about sensitivity, specificity, and predictive values. In this article, therefore, foundations are first established concerning these metrics along …
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Within the context of screening tests, it is important to avoid misconceptions about sensitivity, specificity, and predictive values. In this article, therefore, foundations are first established concerning these metrics along with the first of several aspects of pliability that should be recognized in relation to those metrics. Clarification is then provided about the definitions of sensitivity, specificity, and predictive values and why researchers and clinicians can misunderstand and misrepresent them. Arguments are made that sensitivity and specificity should usually be applied only in the context of describing a screening test's attributes relative to a reference standard; that predictive values are more appropriate and informative in actual screening contexts, but that sensitivity and specificity can be used for screening decisions about individual people if they are extremely high; that predictive values need not always be high and might be used to advantage by adjusting the sensitivity and specificity of screening tests; that, in screening contexts, researchers should provide information about all four metrics and how they were derived; and that, where necessary, consumers of health research should have the skills to interpret those metrics effectively for maximum benefit to clients and the healthcare system.
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265.
白鸟
(2023-10-31 23:02):
#paper https://doi.org/10.1016/j.cell.2022.09.005 Pan-cancer analyses reveal cancer-type-specific fungal ecologies and bacteriome interactions。
研究者一直在探索癌症与微生物之间的关联,研究发现肿瘤组织中存在代谢活跃、免疫反应、细胞内和癌症类型特异性的细菌和病毒群落。但与癌症相关的真菌却很少被研究。文章研究4个独立队列中 35 种癌症类型的 17,401 名患者组织、血液和血浆样本中的癌症真菌组特征。本文的亮点是1.在 35 种癌症类型中检测到真菌,并且通常存在于细胞内;2.在肿瘤中检测到多种真菌-细菌-免疫生态;3.临床分型: 瘤内真菌对分型临床结果,包括免疫治疗反应;4.非细胞而是利用真菌DNA断定健康和早期癌症患者。思考:1.瘤内真菌低丰度检测、技术背景处理,样本类型,实验需要周密设计,剔除假阳性;2.瘤内真菌的作用机制还需实质性系统研究;3.微生物(真菌)和宿主肿瘤组织的关系在肿瘤临床诊治的应用也期待开启。
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No abstract available.
266.
符毓 Yu
(2023-10-31 22:49):
#paper doi:10.1080/03772063.2020.1830862 IETE Journal of Research, 2020, Electric Vehicle Control and Driving Safety Systems: A Review。过去10年汽车电子电气架构正在快速升级中,对应包括动态实时的要求,稳定性等控制的安全测试也需要更新更可靠的测试方法,本文总结了过去和当前的电动汽车不同控制设计的解决方案
Abstract:
No abstract available.
267.
muton
(2023-10-31 22:43):
#paper: https://doi.org/10.1073/pnas.2304085120 Modeling naturalistic face processing in humans with deep convolutional neural networks 大脑在加工信息的过程中,都是一个动态变化的过程,以往使用深度卷积神经网络可以模拟出大脑在记忆过程中的动态变化过程,但是对人脸材料而言,都是基于静态的材料进行解码,少有研究使用深度卷积神经网络的方法来解释大脑加工人脸的过程。由于人脸对于人类而言是具有特殊属性的一类材料,并且具有多维属性,如性别,表情,年龄等等,使用此方法解码是非常必要的。本文中作者使用700多个陌生面孔的自然刺激,每个视频长达4s,结合行为以及FMRI成像数据,对人脸加工过程进行了解码,结果发现,深度卷积神经网络模型在中间层/阶段可以很好的解码出分类情况,此阶段与行为结果也一致(行为结果更多体现出了分类信息),但是在全连接层可能更多体现了其他认知过程,如个性化信息等,神经信号的结果包含了更多动态和其他信息加工的信息。因此此模型可以很好的预测面部分类情况,但是对于随后的认知情况和动态变化情况并不能有一个很好的分类效果,因此,解码人脸动态加工过程的深度卷积神经网络模型仍有待进一步发展。
IF:9.400Q1
Proceedings of the National Academy of Sciences of the United States of America,
2023-10-24.
DOI: 10.1073/pnas.2304085120
PMID: 37847731
Abstract:
Deep convolutional neural networks (DCNNs) trained for face identification can rival and even exceed human-level performance. The ways in which the internal face representations in DCNNs relate to human cognitive …
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Deep convolutional neural networks (DCNNs) trained for face identification can rival and even exceed human-level performance. The ways in which the internal face representations in DCNNs relate to human cognitive representations and brain activity are not well understood. Nearly all previous studies focused on static face image processing with rapid display times and ignored the processing of naturalistic, dynamic information. To address this gap, we developed the largest naturalistic dynamic face stimulus set in human neuroimaging research (700+ naturalistic video clips of unfamiliar faces). We used this naturalistic dataset to compare representational geometries estimated from DCNNs, behavioral responses, and brain responses. We found that DCNN representational geometries were consistent across architectures, cognitive representational geometries were consistent across raters in a behavioral arrangement task, and neural representational geometries in face areas were consistent across brains. Representational geometries in late, fully connected DCNN layers, which are optimized for individuation, were much more weakly correlated with cognitive and neural geometries than were geometries in late-intermediate layers. The late-intermediate face-DCNN layers successfully matched cognitive representational geometries, as measured with a behavioral arrangement task that primarily reflected categorical attributes, and correlated with neural representational geometries in known face-selective topographies. Our study suggests that current DCNNs successfully capture neural cognitive processes for categorical attributes of faces but less accurately capture individuation and dynamic features.
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268.
大勇
(2023-10-31 22:35):
#paper https://doi.org/10.1038/s41586-020-2682-1 Cancer SLC43A2 alters T cell methionine metabolism and histone methylation
本文献以甲硫氨酸代谢为主要内容,肿瘤细胞通过SLC48A2转运体与CD8+T细胞竞争甲硫氨酸,导致T细胞甲硫氨酸摄取减少,从而影响甲硫氨酸代谢,抑制组蛋白H3K79me2,进而抑制了STAT5的通路激活,最终导致CD8+T细胞杀伤功能减退和凋亡增多。
Abstract:
Abnormal epigenetic patterns correlate with effector T cell malfunction in tumours, but the cause of this link is unknown. Here we show that tumour cells disrupt methionine metabolism in CD8 …
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Abnormal epigenetic patterns correlate with effector T cell malfunction in tumours, but the cause of this link is unknown. Here we show that tumour cells disrupt methionine metabolism in CD8 T cells, thereby lowering intracellular levels of methionine and the methyl donor S-adenosylmethionine (SAM) and resulting in loss of dimethylation at lysine 79 of histone H3 (H3K79me2). Loss of H3K79me2 led to low expression of STAT5 and impaired T cell immunity. Mechanistically, tumour cells avidly consumed methionine and outcompeted T cells for methionine by expressing high levels of the methionine transporter SLC43A2. Genetic and biochemical inhibition of tumour SLC43A2 restored H3K79me2 in T cells, thereby boosting spontaneous and checkpoint-induced tumour immunity. Moreover, methionine supplementation improved the expression of H3K79me2 and STAT5 in T cells, and this was accompanied by increased T cell immunity in tumour-bearing mice and patients with colon cancer. Clinically, tumour SLC43A2 correlated negatively with T cell histone methylation and functional gene signatures. Our results identify a mechanistic connection between methionine metabolism, histone patterns, and T cell immunity in the tumour microenvironment. Thus, cancer methionine consumption is an immune evasion mechanism, and targeting cancer methionine signalling may provide an immunotherapeutic approach.
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269.
Ricardo
(2023-10-31 22:15):
#paper https://doi.org/10.48550/arXiv.2308.01316 Patched Denoising Diffusion Models For High-Resolution Image Synthesis 最近在研究如何使用生成模型将脑分割图像映射回T1w/T2w图像,不过大多数医学图像生成算法都是基于patch的,然后将patch在体素空间拼回,但是这样的方法会出现边界不连续的现象。这篇文章提出用patch训练扩散模型,并在特征空间中消除边界效应。因此最近在尝试如何将这个方法应用于我的工作里。最近在做的工作是在全年龄段上构建脑模板图像,有机会可以和大家讲一讲这方面的工作。
arXiv,
2023.
DOI: 10.48550/arXiv.2308.01316
Abstract:
We propose an effective denoising diffusion model for generatinghigh-resolution images (e.g., 1024$\times$512), trained on small-size imagepatches (e.g., 64$\times$64). We name our algorithm Patch-DM, in which a newfeature collage strategy is …
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We propose an effective denoising diffusion model for generatinghigh-resolution images (e.g., 1024$\times$512), trained on small-size imagepatches (e.g., 64$\times$64). We name our algorithm Patch-DM, in which a newfeature collage strategy is designed to avoid the boundary artifact whensynthesizing large-size images. Feature collage systematically crops andcombines partial features of the neighboring patches to predict the features ofa shifted image patch, allowing the seamless generation of the entire image dueto the overlap in the patch feature space. Patch-DM produces high-quality imagesynthesis results on our newly collected dataset of nature images(1024$\times$512), as well as on standard benchmarks of smaller sizes(256$\times$256), including LSUN-Bedroom, LSUN-Church, and FFHQ. We compare ourmethod with previous patch-based generation methods and achievestate-of-the-art FID scores on all four datasets. Further, Patch-DM alsoreduces memory complexity compared to the classic diffusion models.
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270.
尹志
(2023-10-31 19:35):
#paper https://doi.org/10.1063/5.0006074 J. Chem. Phys. 153, 024109 (2020) Recent developments in the PySCF program package, 这是pyscf的一篇介绍性文章,是pyscf主创团队写的,全面介绍了pyscf的目标、功能、应用领域,更重要的是作者详细讲述了pyscf库的设计理念,这个部分相信会比较吸引对科学计算感兴趣的小伙伴。pyscf是一个基于python的量子化学库,对于分子及固体的第一性原理模拟非常友好。自从2014年作者创建该库之后,越来越多从事量子模拟,电子结构计算的小伙伴为这个库做出贡献,现在pyscf不仅在量化领域,在数据科学、机器学习、量子计算领域也占据一席之地。文章写的很细,着重表达了作者团队希望pyscf能够更加松耦合,小结构驱动,成为更大项目的脚手架等设计理念,该理念也使得越来越多的量化项目优先使用pyscf,更大的项目吸取pyscf作为其核心组成部分;除了可用性,团队对性能的追求也使得pyscf成为众多量化软件中出色的候选。文章通过很多例子对上述观点进行了说明,极具可读性和参考价值,比如使用后HF对哈密顿量进行定制,使用一般化的CASSCF solverx实现轨道优化MP2方法,这些例子的代码都在20-30行代码左右,却能比很多书本都讲得清楚。最后,作者也展望了pyscf在机器学习,量子计算等领域的发展。考虑到本人在使用pyscf过程中的良好体验,推荐感兴趣的小伙伴读读这篇文章并尝试使用pyscf。对了,pyscf的作者也是传奇,真正做到了经营着量化基金,开发着量化软件,哈哈哈哈哈哈哈
Abstract:
PySCF is a Python-based general-purpose electronic structure platform that supports first-principles simulations of molecules and solids as well as accelerates the development of new methodology and complex computational workflows. This …
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PySCF is a Python-based general-purpose electronic structure platform that supports first-principles simulations of molecules and solids as well as accelerates the development of new methodology and complex computational workflows. This paper explains the design and philosophy behind PySCF that enables it to meet these twin objectives. With several case studies, we show how users can easily implement their own methods using PySCF as a development environment. We then summarize the capabilities of PySCF for molecular and solid-state simulations. Finally, we describe the growing ecosystem of projects that use PySCF across the domains of quantum chemistry, materials science, machine learning, and quantum information science.
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271.
Vincent
(2023-10-31 14:27):
#paper https://doi.org/10.1038/s41576-022-00477-6 Nat Rev Genet 2022 Making sense of the ageing methylome
衰老近些年引起了比较大的研究兴趣。这篇综述文章总结了近些年关于衰老的甲基化组学研究。文章介绍了寻找衰老关联位点的几种统计方法和对应的工具,例如最常见的使用线性模型寻找差异化位点,使用假设检验寻找变异位点,以及通过使用熵值和相关性网络等统计工具寻找更复杂的变化模式。此外文章还介绍了一些有趣的与衰老相关的甲基化证据,探讨了通过干预甲基化模式与机制来达到延长寿命的策略。最后文章还讨论了甲基化年龄机理的相关理论。
Abstract:
Over time, the human DNA methylation landscape accrues substantial damage, which has been associated with a broad range of age-related diseases, including cardiovascular disease and cancer. Various age-related DNA methylation …
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Over time, the human DNA methylation landscape accrues substantial damage, which has been associated with a broad range of age-related diseases, including cardiovascular disease and cancer. Various age-related DNA methylation changes have been described, including at the level of individual CpGs, such as differential and variable methylation, and at the level of the whole methylome, including entropy and correlation networks. Here, we review these changes in the ageing methylome as well as the statistical tools that can be used to quantify them. We detail the evidence linking DNA methylation to ageing phenotypes and the longevity strategies aimed at altering both DNA methylation patterns and machinery to extend healthspan and lifespan. Lastly, we discuss theories on the mechanistic causes of epigenetic ageing.
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272.
李翛然
(2023-10-31 13:21):
#paper doi:10.1093/bioinformatics/btad596 DeepCCI: a deep learning framework for identifying cell-cell interactions from single-cell RNA sequencing data
一个新的框架,在用scRNA的数据来解释细胞互作,不过我觉得最大的问题是,看了一下他的训练集和数据集,还是通过对于scRNA的初步处理数据,即做到uMAP的降维分类后就来训练,还是非常初级的想法,真正的细胞互作的机理在这个颗粒度下的解释会很糟糕。不过也算是一个跨领域的应用 值得鼓励
Abstract:
MOTIVATION: Cell-cell interactions (CCIs) play critical roles in many biological processes such as cellular differentiation, tissue homeostasis, and immune response. With the rapid development of high throughput single-cell RNA sequencing …
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MOTIVATION: Cell-cell interactions (CCIs) play critical roles in many biological processes such as cellular differentiation, tissue homeostasis, and immune response. With the rapid development of high throughput single-cell RNA sequencing (scRNA-seq) technologies, it is of high importance to identify CCIs from the ever-increasing scRNA-seq data. However, limited by the algorithmic constraints, current computational methods based on statistical strategies ignore some key latent information contained in scRNA-seq data with high sparsity and heterogeneity.RESULTS: Here, we developed a deep learning framework named DeepCCI to identify meaningful CCIs from scRNA-seq data. Applications of DeepCCI to a wide range of publicly available datasets from diverse technologies and platforms demonstrate its ability to predict significant CCIs accurately and effectively. Powered by the flexible and easy-to-use software, DeepCCI can provide the one-stop solution to discover meaningful intercellular interactions and build CCI networks from scRNA-seq data.AVAILABILITY AND IMPLEMENTATION: The source code of DeepCCI is available online at https://github.com/JiangBioLab/DeepCCI.
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273.
庞庞
(2023-10-31 11:57):
#paper doi:10.1093/schbul/sbaa155 Disrupted Intersubject Variability Architecture in Functional Connectomes in Schizophrenia 精神分裂症是一种高度异质性的疾病,临床表现存在个体差异。 先前在精分进行的神经影像学研究主要集中于识别患者和健康对照 (HC) 之间大脑连接组的组平均差异,忽略了被试间差异。 作者获取了 121 名 精分患者和 183 名 HC 的全脑静息态功能 MRI 数据,并检查了 患者和 HC 功能连接组的个体间差异。 然后,作者评估了 个体间差异 与 患者 临床变量之间的关系。 患者 组的全脑个体间差异模式与 HC 组基本相似。 与HC组相比,精分组在双侧感觉运动、视觉、听觉和皮质下区域表现出更高的个体间差异。 此外,个体间差异的改变与发病年龄、病程和简明精神病评定量表评分呈负相关,与临床异质性呈正相关。 精分中全脑个体间差异的改变对于理解 精分的高度临床异质性以及该疾病未来的个体化临床诊断和治疗具有潜在的意义。
Abstract:
Schizophrenia (SCZ) is a highly heterogeneous disorder with remarkable intersubject variability in clinical presentations. Previous neuroimaging studies in SCZ have primarily focused on identifying group-averaged differences in the brain connectome …
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Schizophrenia (SCZ) is a highly heterogeneous disorder with remarkable intersubject variability in clinical presentations. Previous neuroimaging studies in SCZ have primarily focused on identifying group-averaged differences in the brain connectome between patients and healthy controls (HCs), largely neglecting the intersubject differences among patients. We acquired whole-brain resting-state functional MRI data from 121 SCZ patients and 183 HCs and examined the intersubject variability of the functional connectome (IVFC) in SCZ patients and HCs. Between-group differences were determined using permutation analysis. Then, we evaluated the relationship between IVFC and clinical variables in SCZ. Finally, we used datasets of patients with bipolar disorder (BD) and major depressive disorder (MDD) to assess the specificity of IVFC alteration in SCZ. The whole-brain IVFC pattern in the SCZ group was generally similar to that in HCs. Compared with the HC group, the SCZ group exhibited higher IVFC in the bilateral sensorimotor, visual, auditory, and subcortical regions. Moreover, altered IVFC was negatively correlated with age of onset, illness duration, and Brief Psychiatric Rating Scale scores and positively correlated with clinical heterogeneity. Although the SCZ shared altered IVFC in the visual cortex with BD and MDD, the alterations of IVFC in the sensorimotor, auditory, and subcortical cortices were specific to SCZ. The alterations of whole-brain IVFC in SCZ have potential implications for the understanding of the high clinical heterogeneity of SCZ and the future individualized clinical diagnosis and treatment of this disease.
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274.
小年
(2023-10-30 22:31):
#paper Andrews G, Fan K, Pratt HE, Phalke N; Zoonomia Consortium§; Karlsson EK, Lindblad-Toh K, Gazal S, Moore JE, Weng Z. Mammalian evolution of human cis-regulatory elements and transcription factor binding sites. Science. 2023 Apr 28;380(6643):eabn7930. doi: 10.1126/science.abn7930. Epub 2023 Apr 28. PMID: 37104580.
哺乳动物之所以具有高度的生物体复杂性,很大程度上是由于它们的蛋白质调节的多样性。描述人类基因组的调控景观是现代生物学的一个长期目标。现代方法测量全基因组的生化信号,包括染色质可及性、组蛋白修饰、DNA甲基化和人类基因组中约1600个转录因子(tf)的结合。本篇文章作者利用Zoonomia项目(Zoonomia project)开发的工具---胎盘哺乳动物的进化限制(evolutionary constraint)和无参考基因组的241种哺乳动物的基因组比对---对胎盘哺乳动物的进化动态进行了研究。作者探索了从表观基因组学数据中获得的ENCODE cCRE和从染色质免疫沉淀数据中获得的367种转录因子的结合位点。他们发现了哺乳动物调控元件的保护性图谱:一端是高度保守的cCRE和进化受限的TFBS,另一端是灵长类动物特有的与转座因子(transposable element)重叠的cCRE和TFBSs。保守性的调控元件主要位于在基本细胞过程(代谢、发育)中起作用的基因附近,并且在其他哺乳动物的基因组中往往具有功能性,而不存在进化限制的调控元件位于涉及与环境相互作用的基因附近。
Abstract:
Understanding the regulatory landscape of the human genome is a long-standing objective of modern biology. Using the reference-free alignment across 241 mammalian genomes produced by the Zoonomia Consortium, we charted …
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Understanding the regulatory landscape of the human genome is a long-standing objective of modern biology. Using the reference-free alignment across 241 mammalian genomes produced by the Zoonomia Consortium, we charted evolutionary trajectories for 0.92 million human candidate cis-regulatory elements (cCREs) and 15.6 million human transcription factor binding sites (TFBSs). We identified 439,461 cCREs and 2,024,062 TFBSs under evolutionary constraint. Genes near constrained elements perform fundamental cellular processes, whereas genes near primate-specific elements are involved in environmental interaction, including odor perception and immune response. About 20% of TFBSs are transposable element-derived and exhibit intricate patterns of gains and losses during primate evolution whereas sequence variants associated with complex traits are enriched in constrained TFBSs. Our annotations illuminate the regulatory functions of the human genome.
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275.
四封信之林
(2023-10-30 21:22):
#paper 专利:Equalization-based image processing and spatial crosstalk attenuator。pub.No: US 2021/0350163 A1。针对基因测序过程中,cluster点之间的空间串扰的问题(cluster之间距离过近会导致,cluster之间存在信号干扰,从而导致测序错误率升高)。该专利通过机器学习的方式来得到一个提取亮度的卷积核。通过cluster重心在像素中的亚像素位置,将cluster划分为25类,然后以信噪比(或指定亮度为目标),来进行梯度下降学习到每类cluster的亮度提取卷积,从而实现去除空间串扰的作用。
2021.
Abstract:
No abstract available.
276.
哪有情可长
(2023-10-30 21:15):
#paper Genome resources for the elite bread wheat cultivar Aikang 58 and mining of elite homeologous haplotypes for accelerating wheat improvement,Molecular Plant, 23 October 2023, doi.org/10.1016/j.molp.2023.10.015. AK58是在2005年国家审定的具有矮杆抗倒伏,稳产多抗,适应性广品质优的一个小麦品种,该品种在全国推广范围较大,在2013年获得“国家科技进步一等奖”。该品种作为人工培育的经典的现代品种跟小麦参考基因组地方种中国春相比较的话,能够揭示小麦近百年来小麦品种改良造成的基因组变异。作者构建了AK58基因、转座子、转录组、表观组、代谢组和突变体等综合的数据库。 利用比较基因组学对AK58和中国春进行比较分析,发现AK58特意表达的基因主要在光系统Ⅰ、损伤反应及氧化磷酸化途径中显著富集,而中国春的特异表达基因在植物与病原物互作途径中得到富集。在六倍体小麦中由于亚基因组二倍化与分化,使得每个多倍体位点中三个亚基因组的直系同源基因,通常显示出既有互补性又有特异性的功能。在F2遗传群体中,两个亲本的等位亚基因组直系同源基因间会发生多达27种(33)的组合,其中2种为亲本类型,而另外25种为新组合类型,每一种组合类型都有可能是一种功能独特的多倍体位点单倍型(homoeologous locus haplotype, HH),从而大大提高了六倍体小麦的遗传多样性。为便于研究,研究人员利用SNP芯片分析了AK58与CS衍生的F2群体,以特异的SNP标记重要多倍体位点的每一个亚基因组拷贝,从而可方便地区分由等位亚基因组直系同源基因组合而产生的多种HHs,并以其为基因型信息与农艺性状进行关联分析。这种基于多倍体位点单倍型差异的关联分析有别于常规的依赖单基因差异的关联分析,因而被称为HGWAS。用该方法对20个重要农艺性状进行检测,共发现393个显著的HGWAS位点,针对重要的HGWAS位点,研究人员进行了不同HHs之间遗传效应的比较。在AK58与CS中均发现了多种优异的HHs,源于AK58的HHs反映了现代育种的选择效应,存在于CS的HHs可能在现代育种选择中被遗弃,但可能仍然有利用价值。
Abstract:
Despite recent progress in crop genomics studies, the genomic changes brought about by modern breeding selection are still poorly understood, thus hampering genomics-assisted breeding, especially in polyploid crops with compound …
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Despite recent progress in crop genomics studies, the genomic changes brought about by modern breeding selection are still poorly understood, thus hampering genomics-assisted breeding, especially in polyploid crops with compound genomes such as common wheat (Triticum aestivum). In this work, we constructed genome resources for the modern elite common wheat variety Aikang 58 (AK58). Comparative genomics between AK58 and the landrace cultivar Chinese Spring (CS) shed light on genomic changes that occurred through recent varietal improvement. We also explored subgenome diploidization and divergence in common wheat and developed a homoeologous locus-based genome-wide association study (HGWAS) approach, which was more effective than single homoeolog-based GWAS in unraveling agronomic trait-associated loci. A total of 123 major HGWAS loci were detected using a genetic population derived from AK58 and CS. Elite homoeologous haplotypes (HHs), formed by combinations of subgenomic homoeologs of the associated loci, were found in both parents and progeny, and many could substantially improve wheat yield and related traits. We built a website where users can download genome assembly sequence and annotation data for AK58, perform blast analysis, and run JBrowse. Our work enriches genome resources for wheat, provides new insights into genomic changes during modern wheat improvement, and suggests that efficient mining of elite HHs can make a substantial contribution to genomics-assisted breeding in common wheat and other polyploid crops.
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277.
芝麻
(2023-10-30 16:32):
#paper DOI: 10.1136/gutjnl-2020-320930 Exploring prognostic indicators in the pathological images of hepatocellular carcinoma based on deep learning 肿瘤病理学包含丰富的信息,包括组织结构和细胞形态,反映疾病进展和患者生存情况。 然而,表型信息微妙而复杂,使得从病理图像中发现预后指标具有挑战性。本文基于深度学习探索肝细胞癌病理图像中的预后指标,通过AI发现一个很好的临床指标,它不仅在中国人群中做出了差异,还在tcga里做了验证,作为一个与其他因素独立的marker,hr达到3.5,是一个利用AI提高患者预后准确率的成功案例
Abstract:
OBJECTIVE: Tumour pathology contains rich information, including tissue structure and cell morphology, that reflects disease progression and patient survival. However, phenotypic information is subtle and complex, making the discovery of …
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OBJECTIVE: Tumour pathology contains rich information, including tissue structure and cell morphology, that reflects disease progression and patient survival. However, phenotypic information is subtle and complex, making the discovery of prognostic indicators from pathological images challenging.DESIGN: An interpretable, weakly supervised deep learning framework incorporating prior knowledge was proposed to analyse hepatocellular carcinoma (HCC) and explore new prognostic phenotypes on pathological whole-slide images (WSIs) from the Zhongshan cohort of 1125 HCC patients (2451 WSIs) and TCGA cohort of 320 HCC patients (320 WSIs). A 'tumour risk score (TRS)' was established to evaluate patient outcomes, and then risk activation mapping (RAM) was applied to visualise the pathological phenotypes of TRS. The multi-omics data of The Cancer Genome Atlas(TCGA) HCC were used to assess the potential pathogenesis underlying TRS.RESULTS: Survival analysis revealed that TRS was an independent prognosticator in both the Zhongshan cohort (p<0.0001) and TCGA cohort (p=0.0003). The predictive ability of TRS was superior to and independent of clinical staging systems, and TRS could evenly stratify patients into up to five groups with significantly different prognoses. Notably, sinusoidal capillarisation, prominent nucleoli and karyotheca, the nucleus/cytoplasm ratio and infiltrating inflammatory cells were identified as the main underlying features of TRS. The multi-omics data of TCGA HCC hint at the relevance of TRS to tumour immune infiltration and genetic alterations such as the FAT3 and RYR2 mutations.CONCLUSION: Our deep learning framework is an effective and labour-saving method for decoding pathological images, providing a valuable means for HCC risk stratification and precise patient treatment.
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278.
钟鸣
(2023-10-30 16:06):
#paper doi: 10.1128/jb.00165-23 Three genes controlling streptomycin susceptibility in Agrobacterium fabrum 链霉素是一种氨基糖苷类抗生素,通过干扰16S rRNA的正常工作阻碍细菌复制,实现抗菌效果。农杆菌的链霉素抗性通常由rpsL、rsmG(也称为gidB)和rrs突变引起。本课题中,作者使用链霉菌做连续培养筛选和分析,获取了在低浓度和高浓度抗生素下筛选到的耐药菌准,由于传代筛选过程中未引入外源基因,表明内源性基因的突变调控了耐药性。由于低浓度下的突变体的耐药性高于高浓度下的突变体,因此作者分别对这两批突变体进行了测序。作者首先发现高浓度突变株的rpsL发生了突变而低浓度的没有,对突变的rpsL等位基因进行转移实现,验证了该等位基因能赋予野生型耐药性。对6株低浓度突变体的测序发现,都发生了导致rsmG功能丧失的突变,随后的敲除和回补实证实了该基因突变对链霉素抗性的影响。
Abstract:
ABSTRACT Streptomycin (Sm) is a commonly used antibiotic for its efficacy against diverse bacteria. The plant pathogen Agrobacterium fabrum is a model for studying pathogenesis and interkingdom gene transfer. Streptomycin-resistant …
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ABSTRACT Streptomycin (Sm) is a commonly used antibiotic for its efficacy against diverse bacteria. The plant pathogen Agrobacterium fabrum is a model for studying pathogenesis and interkingdom gene transfer. Streptomycin-resistant variants of A. fabrum are commonly employed in genetic analyses, yet mechanisms of resistance and susceptibility to streptomycin in this organism have not previously been investigated. We observe that resistance to a high concentration of streptomycin arises at high frequency in A. fabrum , and we attribute this trait to the presence of a chromosomal gene ( strB ) encoding a putative aminoglycoside phosphotransferase. We show how strB , along with rpsL (encoding ribosomal protein S12) and rsmG (encoding a 16S rRNA methyltransferase), modulates streptomycin sensitivity in A. fabrum . IMPORTANCE The plant pathogen Agrobacterium fabrum is a widely used model bacterium for studying biofilms, bacterial motility, pathogenesis, and gene transfer from bacteria to plants. Streptomycin (Sm) is an aminoglycoside antibiotic known for its broad efficacy against gram-negative bacteria. A. fabrum exhibits endogenous resistance to somewhat high levels of streptomycin, but the mechanism underlying this resistance has not been elucidated. Here, we demonstrate that this resistance is caused by a chromosomally encoded streptomycin-inactivating enzyme, StrB, that has not been previously characterized in A. fabrum . Furthermore, we show how the genes rsmG , rpsL , and strB jointly modulate streptomycin susceptibility in A. fabrum .
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279.
前进
(2023-10-30 13:57):
#paper https://doi.org/10.1088/1361-6560/ac5f70
Training low dose CT denoising network without high quality
reference data
低剂量CT(LDCT)去噪领域主要是基于监督学习的方法,需要完全配准的LDCT对及其相应的干净参考图像(normal-dose CT)。然而,无干净标签的训练更具有实际意义,因为在临床上不可能获得大量的这些配对样本。本文提出了一种用于LDCT成像的自监督去噪方法。方法该方法不需要任何干净的图像。此外,在去噪过程中,利用感知损失来实现特征域的数据一致性。在解码阶段使用的注意块可以帮助进一步提高图像质量。在实验中横向对比了3种方法,并进行了6个消融实验,验证了提出的自监督框架的有效性,以及自注意模块和感知损失的有效性。
IF:3.300Q1
Physics in medicine and biology,
2022-04-11.
DOI: 10.1088/1361-6560/ac5f70
PMID: 35313298
Abstract:
Currently, the field of low-dose CT (LDCT) denoising is dominated by supervised learning based methods, which need perfectly registered pairs of LDCT and its corresponding clean reference image (normal-dose CT). …
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Currently, the field of low-dose CT (LDCT) denoising is dominated by supervised learning based methods, which need perfectly registered pairs of LDCT and its corresponding clean reference image (normal-dose CT). However, training without clean labels is more practically feasible and significant, since it is clinically impossible to acquire a large amount of these paired samples. In this paper, a self-supervised denoising method is proposed for LDCT imaging.The proposed method does not require any clean images. In addition, the perceptual loss is used to achieve data consistency in feature domain during the denoising process. Attention blocks used in decoding phase can help further improve the image quality.In the experiments, we validate the effectiveness of our proposed self-supervised framework and compare our method with several state-of-the-art supervised and unsupervised methods. The results show that our proposed model achieves competitive performance in both qualitative and quantitative aspects to other methods.Our framework can be directly applied to most denoising scenarios without collecting pairs of training data, which is more flexible for real clinical scenario.
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280.
惊鸿
(2023-10-30 11:51):
#paper DOI:10.1007/s00417-023-06158-2 Pub Date:2023-06-30 Comparisons of the protein expressions between high myopia and moderate myopia on the anterior corneal stroma in human
这篇文章告诉了前角膜基质上存在高度近视和中度近视之间的36个DEP,其中11个蛋白上调,25个蛋白下调。GO分析显示,高度近视角膜中角质细胞迁移和细胞骨架结构成分发生显着变化,大部分蛋白质减少。角蛋白 16 (KRT16) 和红细胞膜蛋白带 4.1 样蛋白 4B 是仅有的两种参与这两种功能的蛋白。PPI 分析显示角蛋白 II 型细胞骨架 6A (KRT6A) 和 KRT16 具有很强的联系。免疫球蛋白lambda变量8-61(IGLV8-61)和烟酰胺磷酸核糖转移酶(NAMPT)与TMT的结果一致。
得出结论为与中度近视角膜相比,高度近视角膜在前角膜基质上有 36 个 DEP。高度近视眼角膜的角质形成细胞迁移和细胞骨架的结构成分减弱,这可能部分解释了高度近视眼角膜生物力学较低的原因。较低表达的KRT16在高度近视角膜中发挥重要作用。
Abstract:
PURPOSE: To investigate the differentially expressed proteins (DEP) between high myopia and moderate myopia on the anterior corneal stroma.METHODS: Tandem mass tag (TMT) quantitative proteomics was utilized to reveal proteins. …
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PURPOSE: To investigate the differentially expressed proteins (DEP) between high myopia and moderate myopia on the anterior corneal stroma.METHODS: Tandem mass tag (TMT) quantitative proteomics was utilized to reveal proteins. DEPs were screened by the multiple change of more than 1.2 times or less than 0.83 and the P value < 0.05. The DEPs were functional annotated by Gene Ontology (GO) terms. Proteins and protein interaction (PPI) networks were conducted with String online tool. Parallel reaction monitoring (PRM) data processing was used to verify the TMT proteomics results.RESULTS: There are 36 DEPs between high myopia and moderate myopia on the anterior corneal stroma, of which 11 proteins are upregulated, 25 proteins are downregulated. The GO analysis demonstrated keratinocyte migration and structural constituent of cytoskeleton that are significantly changed with most of the proteins decreased in high myopic corneas. Keratin 16 (KRT16) and erythrocyte membrane protein band 4.1-like protein 4B are the only two proteins involved in both functions. The PPI analysis showed keratin type II cytoskeletal 6A (KRT6A) and KRT16 that have strong connections. Immunoglobulin lambda variable 8-61(IGLV8-61) and nicotinamide phosphoribosyl transferase (NAMPT) have consistent results with the TMT.CONCLUSIONS: The high myopic corneas have 36 DEPs compared to the moderate myopic corneas on the anterior corneal stroma. Keratinocyte migrations and structural constituent of cytoskeleton are weakened in high myopic corneas, which may partly account for the lower corneal biomechanics in high myopic eyes. The lower expressed KRT16 plays important roles in high myopic corneas.
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