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581.
muton (2022-12-31 22:43):
#paper doi: https://doi.org/10.1101/2022.10.03.510672 Human hippocampal ripples signal encoding of episodic memories biorixv 2022 海马尖波涟漪是在哺乳动物电生理中发现的一个很特别具有代表性的成分,最开始是在小鼠研究中被发现,随着人类脑电记录的发展,颅内记录的出现让研究尖波涟漪在人类中变为现实,以往在人类的研究中更多关注于ripple和记忆提取之间的关系,很少研究在编码信息,尤其是单个项目时ripple的作用,本文则填补了这一空白,通过124名被试的情景记忆任务表现,作者发现虽然在MTL等重要脑区能够发现高频信号的随后记忆效应,但ripple并未表现出差异,但令人新奇的是ripple会在记忆item在编码时间上相近或语义相近的item时表现出更频繁的发放,也被称为一种聚类效应,并且这一现象在编码和提取阶段都能够被发现,这种现象可能代表了一种对于记忆的保留,有助于预测和提取记忆。本篇文章对于探究ripple这一脑电成分在人类情景记忆中的功能有重要提示。
Abstract:
AbstractRecent human electrophysiology work has uncovered the presence of high frequency oscillatory events, termed ripples, during awake behavior. This prior work focuses on ripples in the medial temporal lobe (MTL) … >>>
AbstractRecent human electrophysiology work has uncovered the presence of high frequency oscillatory events, termed ripples, during awake behavior. This prior work focuses on ripples in the medial temporal lobe (MTL) during memory retrieval. Few studies, however, investigate ripples during item encoding. Many studies have found neural activity during encoding that predicts later recall, termed subsequent memory effects (SMEs), but it is unclear if ripples during encoding also predict subsequent recall. Detecting ripples in 124 neurosurgical participants performing an episodic memory task, we find insignificant ripple SMEs in any MTL region, even as these regions exhibit robust high frequency activity (HFA) SMEs. Instead, hippocampal ripples increase during encoding of items leading to recall of temporally or semantically associated items, a phenomenon known as clustering. This subsequent clustering effect (SCE) arises specifically when hippocampal ripples occur during both encoding and retrieval, suggesting that ripples mediate the encoding and future reinstatement of episodic memories. <<<
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582.
(2022-12-31 22:41):
#paper Differential gene expression in dairy cows under negative energy balance and ketosis: A systematic review and meta-analysis. J Dairy Sci. 2021 Jan;104(1):602-615. doi: 10.3168/jds.2020-18883. 为了评估负能量平衡(NEB)、亚临床和临床酮症奶牛肝脏中差异基因表达的模式,该文筛选了NEB和临床和亚临床酮症期间基因表达的同行评审和相关文章(其中考虑到血浆β-羟基丁酸盐水平),创建维恩图以整合系统综述中获得的数据,并使用官方基因名称进行基因本体富集分析,确定了三种重要的代谢途径与NEB和亚临床和临床酮症相关。基因网络分析揭示了34个与脂肪酸转运和脂肪酸代谢功能相关的基因之间的共表达相互作用。在标记的QTL中,鉴定出9个与酮症相关的QTL。基因表达和GWAS数据的整合为奶牛NEB和亚临床和临床酮症的遗传背景提供了额外的理解。
IF:3.700Q2 Journal of dairy science, 2021-Jan. DOI: 10.3168/jds.2020-18883 PMID: 33189279
Abstract:
Development of ketosis in high-producing dairy cows contributes to several animal health issues and highlights the need for a better understanding of the genetic basis of metabolic diseases. To evaluate … >>>
Development of ketosis in high-producing dairy cows contributes to several animal health issues and highlights the need for a better understanding of the genetic basis of metabolic diseases. To evaluate the pattern of differential gene expression in the liver of cows under negative energy balance (NEB), and under subclinical and clinical ketosis, a meta-analysis of gene expression and genome-wide association studies results was performed. An initial systematic review identified 118 articles based on the key words "cow," "liver," "negative energy balance," "ketosis," "expression," "qPCR," "microarray," "proteomic," "RNA-Seq," and "GWAS." After further screening for only peer-reviewed and pertinent articles for gene expression during NEB and clinical and subclinical ketosis (considering plasma levels of β-hydroxybutyrate), 20 articles were included in the analysis. From the systematic review, 430 significant SNPs identified by genome-wide association studies (GWAS) were assigned to genes reported in gene expression studies by considering chromosome and base pair positions in the ARS-UCD 1.2 bovine assembly. Venn diagrams were created to integrate the data obtained in the systematic review, and Gene Ontology enrichment analysis was carried out using official gene names. A QTL enrichment analysis was also performed to identify potential positional candidate loci. Twenty-four significant SNPs were located within the coordinates of differentially expressed genes located on chromosomes 2, 3, 6, 9, 11, 14, 27, and 29. Three significant metabolic pathways were associated with NEB and subclinical and clinical ketosis. In addition, 2 important genes, PPARA (peroxisome proliferator activated receptor alpha) and ACACA (acetyl-coenzyme A carboxylase α), were identified, which were differentially expressed in the 3 metabolic conditions. The PPARA gene is involved in the regulation of lipid metabolism and fatty liver disease and the ACACA gene encodes an enzyme that catalyzes the carboxylation of acetyl-coenzyme A to malonyl-coenzyme A, which is a rate-limiting step in fatty acid synthesis. Gene network analysis revealed co-expression interactions among 34 genes associated with functions involving fatty acid transport and fatty acid metabolism. For the annotated QTL, 9 QTL were identified for ketosis. The genes FN1 (fibronectin 1) and PTK2 (protein tyrosine kinase 2), which are mainly involved in cell adhesion and formation of extracellular matrix constituents, were enriched for QTL previously associated with the trait "ketosis" on chromosome 2 and for the trait "milk iron content" on chromosome 14, respectively. This integration of gene expression and GWAS data provides an additional understanding of the genetic background of NEB and subclinical and clinical ketosis in dairy cattle. Thus, it is a useful approach to identify biological mechanisms underlying these metabolic conditions in dairy cattle. <<<
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583.
小擎子 (2022-12-31 22:08):
#paper doi: 10.1016/j.xgen.2022.100179. Cell Genom, 2022, Uncovering novel mutational signatures by de novo extraction with SigProfilerExtractor。COSMIC网站推荐的检测肿瘤特征的工具,文献主推SigProfilerExtractor,也测试了另外13种检测肿瘤特征的工具。文献做了广泛的数据模拟,添加不同的噪声干扰,比较不同工具的算法表现,做了肿瘤特征提取较为可靠的benchmarking。
IF:11.100Q1 Cell genomics, 2022-Nov-09. DOI: 10.1016/j.xgen.2022.100179 PMID: 36388765
Abstract:
Mutational signature analysis is commonly performed in cancer genomic studies. Here, we present SigProfilerExtractor, an automated tool for extraction of mutational signatures, and benchmark it against another 13 bioinformatics tools … >>>
Mutational signature analysis is commonly performed in cancer genomic studies. Here, we present SigProfilerExtractor, an automated tool for extraction of mutational signatures, and benchmark it against another 13 bioinformatics tools by using 34 scenarios encompassing 2,500 simulated signatures found in 60,000 synthetic genomes and 20,000 synthetic exomes. For simulations with 5% noise, reflecting high-quality datasets, SigProfilerExtractor outperforms other approaches by elucidating between 20% and 50% more true-positive signatures while yielding 5-fold less false-positive signatures. Applying SigProfilerExtractor to 4,643 whole-genome- and 19,184 whole-exome-sequenced cancers reveals four novel signatures. Two of the signatures are confirmed in independent cohorts, and one of these signatures is associated with tobacco smoking. In summary, this report provides a reference tool for analysis of mutational signatures, a comprehensive benchmarking of bioinformatics tools for extracting signatures, and several novel mutational signatures, including one putatively attributed to direct tobacco smoking mutagenesis in bladder tissues. <<<
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584.
张贝 (2022-12-31 21:51):
#paper Pan-cancer analyses reveal cancer-type-specific fungal ecologies and bacteriome interactions. Cell. 2022 Sep 29;185(20):3789-3806.e17. doi:10.1016/j.cell.2022.09.005. 本文通过对包括TCGA数据库在内的四个独立队列中的35种癌症类型的17,401名患者的组织和血液中的真菌群落进行全面表征,研究队列使用的测序方法包括ITS2扩增子测序、WGS及RNA-Seq。研究结果表明真菌普遍存在于多种肿瘤内,且不同癌症类型具有癌症特异性真菌群。肿瘤内真菌-细菌-免疫细胞相互作用分析表明真菌-细菌-免疫细胞间的关联性相对“宽容”,而非此消彼长的竞争关系,最后本文探索了真菌在癌症预后和诊断中的应用。本研究的意义在于构建了首个泛癌真菌微生物组图谱,为癌症与真菌的关系提供清晰的联系。
IF:45.500Q1 Cell, 2022. DOI: 10.1016/j.cell.2022.09.005
Abstract:
Cancer-microbe associations have been explored for centuries, but cancer-associated fungi have rarely been examined. Here, we comprehensively characterize the cancer mycobiome within 17,401 patient tissue, blood, and plasma samples across … >>>
Cancer-microbe associations have been explored for centuries, but cancer-associated fungi have rarely been examined. Here, we comprehensively characterize the cancer mycobiome within 17,401 patient tissue, blood, and plasma samples across 35 cancer types in four independent cohorts. We report fungal DNA and cells at low abundances across many major human cancers, with differences in community compositions that differ among cancer types, even when accounting for technical background. Fungal histological staining of tissue microarrays supported intratumoral presence and frequent spatial association with cancer cells and macrophages. Comparing intratumoral fungal communities with matched bacteriomes and immunomes revealed co-occurring bi-domain ecologies, often with permissive, rather than competitive, microenvironments and distinct immune responses. Clinically focused assessments suggested prognostic and diagnostic capacities of the tissue and plasma mycobiomes, even in stage I cancers, and synergistic predictive performance with bacteriomes. <<<
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585.
钟鸣 (2022-12-31 19:23):
#paper Reverse-transcribed SARS-CoV-2 RNA can integrate into the genome of cultured human cells and can be expressed in patient-derived tissues https://doi.org/10.1073/pnas.2105968118 许多新冠感染者康复后依然能通过PCR检测到病毒,但是却分离不到活病毒,考虑到新冠病毒是一种RNA病毒,因此合理怀疑其逆转录整合到了宿主基因组上。为了证实,作者使用了三种测序方法来对人类细胞来源的基因组测序,结果均发现了新冠基因组。此外作者还回顾了感染者组织来源的RNA测序数据,发现了包括新冠在内的许多病毒的转录本。比较简单的一篇论文,比较可看的地方是讨论。
Abstract:
Prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and recurrence of PCR-positive tests have been widely reported in patients after recovery from COVID-19, but some of these … >>>
Prolonged detection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA and recurrence of PCR-positive tests have been widely reported in patients after recovery from COVID-19, but some of these patients do not appear to shed infectious virus. We investigated the possibility that SARS-CoV-2 RNAs can be reverse-transcribed and integrated into the DNA of human cells in culture and that transcription of the integrated sequences might account for some of the positive PCR tests seen in patients. In support of this hypothesis, we found that DNA copies of SARS-CoV-2 sequences can be integrated into the genome of infected human cells. We found target site duplications flanking the viral sequences and consensus LINE1 endonuclease recognition sequences at the integration sites, consistent with a LINE1 retrotransposon-mediated, target-primed reverse transcription and retroposition mechanism. We also found, in some patient-derived tissues, evidence suggesting that a large fraction of the viral sequences is transcribed from integrated DNA copies of viral sequences, generating viral-host chimeric transcripts. The integration and transcription of viral sequences may thus contribute to the detection of viral RNA by PCR in patients after infection and clinical recovery. Because we have detected only subgenomic sequences derived mainly from the 3' end of the viral genome integrated into the DNA of the host cell, infectious virus cannot be produced from the integrated subgenomic SARS-CoV-2 sequences. <<<
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586.
周周复始 (2022-12-31 19:22):
#paper A 4D infant brain volumetric atlas based on the UNC/UMN baby connectome project (BCP) cohort,NeuroImage,2022,https://doi.org/10.1016/j.neuroimage.2022.119097 时空婴儿脑图谱对于分析早期动态大脑发育至关重要。 但由于婴儿大脑 MR 图像的收集和处理存在巨大挑战,紧密覆盖婴儿期大脑动态发育各个年龄段的4D 图谱仍然很少。 现有的图谱存在组织对比度和低时空分辨率的问题,使得后续分析的准确性下降。 为了解决这个问题,本文基于 UNC/UMN Baby Connectome Project (BCP) 数据集构建了婴儿大脑的 4D 结构 MRI 图谱,该数据集具有高空间分辨率、广泛的年龄范围和密集的采样时间 点。 为了提高联合配准的精确度,采用了最先进的配准方法,并利用脑组织概率图以及强度图像改善单个图像的对齐方式。 为了在婴儿和成人脑图像上实现一致的区域标记以促进跨年龄的基于区域的分析,通过遵循年龄递减的映射方式将广泛使用的 Desikan 皮层分割映射到我们的图谱上。 同时,人工勾画出了典型的皮层下结构,方便皮层下相关研究。 与现有的婴儿脑图谱相比,本文图谱具有更高的时空分辨率并保留了更多的结构细节,因此可以提高婴儿期神经发育分析的准确性。
Abstract:
Spatiotemporal (four-dimensional) infant-dedicated brain atlases are essential for neuroimaging analysis of early dynamic brain development. However, due to the substantial technical challenges in the acquisition and processing of infant brain … >>>
Spatiotemporal (four-dimensional) infant-dedicated brain atlases are essential for neuroimaging analysis of early dynamic brain development. However, due to the substantial technical challenges in the acquisition and processing of infant brain MR images, 4D atlases densely covering the dynamic brain development during infancy are still scarce. Few existing ones generally have fuzzy tissue contrast and low spatiotemporal resolution, leading to degraded accuracy of atlas-based normalization and subsequent analyses. To address this issue, in this paper, we construct a 4D structural MRI atlas for infant brains based on the UNC/UMN Baby Connectome Project (BCP) dataset, which features a high spatial resolution, extensive age-range coverage, and densely sampled time points. Specifically, 542 longitudinal T1w and T2w scans from 240 typically developing infants up to 26-month of age were utilized for our atlas construction. To improve the co-registration accuracy of the infant brain images, which typically exhibit dynamic appearance with low tissue contrast, we employed the state-of-the-art registration method and leveraged our generated reliable brain tissue probability maps in addition to the intensity images to improve the alignment of individual images. To achieve consistent region labeling on both infant and adult brain images for facilitating region-based analysis across ages, we mapped the widely used Desikan cortical parcellation onto our atlas by following an age-decreasing mapping manner. Meanwhile, the typical subcortical structures were manually delineated to facilitate the studies related to the subcortex. Compared with the existing infant brain atlases, our 4D atlas has much higher spatiotemporal resolution and preserves more structural details, and thus can boost accuracy in neurodevelopmental analysis during infancy. <<<
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587.
庞庞 (2022-12-31 18:17):
#paper Causes and Consequences of Diagnostic Heterogeneity in Depression: Paths to Discovering Novel Biological Depression Subtypes https://doi.org/10.1016/j.biopsych.2020.01.012 抑郁症是一种高度异质性的综合症。 该综述文章回顾了抑郁症诊断异质性的主要原因。 并讨论使用数据驱动策略根据功能性神经影像学测量发现新的抑郁症亚型的前景,包括维度、分类和混合方法来解析诊断异质性和理解其生物学基础。 最后,文章考虑了使用静息态功能磁共振成像功能连接技术进行子类型化的优点以及一系列技术挑战和潜在解决方案。
Abstract:
Depression is a highly heterogeneous syndrome that bears only modest correlations with its biological substrates, motivating a renewed interest in rethinking our approach to diagnosing depression for research purposes and … >>>
Depression is a highly heterogeneous syndrome that bears only modest correlations with its biological substrates, motivating a renewed interest in rethinking our approach to diagnosing depression for research purposes and new efforts to discover subtypes of depression anchored in biology. Here, we review the major causes of diagnostic heterogeneity in depression, with consideration of both clinical symptoms and behaviors (symptomatology and trajectory of depressive episodes) and biology (genetics and sexually dimorphic factors). Next, we discuss the promise of using data-driven strategies to discover novel subtypes of depression based on functional neuroimaging measures, including dimensional, categorical, and hybrid approaches to parsing diagnostic heterogeneity and understanding its biological basis. The merits of using resting-state functional magnetic resonance imaging functional connectivity techniques for subtyping are considered along with a set of technical challenges and potential solutions. We conclude by identifying promising future directions for defining neurobiologically informed depression subtypes and leveraging them in the future for predicting treatment outcomes and informing clinical decision making. <<<
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588.
Vincent (2022-12-31 17:51):
#paper DNA methylation aging clocks: challenges and recommendations, Genome Biology, 2019, https://doi.org/10.1186/s13059-019-1824-y 衰老通常伴随着疾病的发生,理解人类为何以及如何衰老是生物学中的重要课题。衰老伴随着分子层面的变化,过去十年内,不少研究发现可以使用基因组上的一部分CpG位点甲基化水平来准确预测年龄,这样的一组CpG位点又被称为 表观遗传时钟。事实上表观遗传时钟的预测误差与疾病发生率和死亡率也被发现有联系,从而广泛引起了研究者们的兴趣。这篇综述文章总结了表观遗传时钟领域的如下七大挑战,并分别介绍了研究现状,不确定性和未来研究方向的推荐:1. 拆分表观时钟的时序成分和生物成分;2. 组织特异或者疾病特异时钟的功能性研究;3.大规模时序种群研究的表观遗传学整合; 4. 衰老的全基因组分析以及其他表观遗传标记物的探索;5. 衰老与疾病的单细胞组学分析; 6. 稳健产生其他物种的衰老数据; 7. 将表观遗传学与遗传学的伦理和法律框架融合起来。个人感觉文章质量一般
IF:10.100Q1 Genome biology, 2019-11-25. DOI: 10.1186/s13059-019-1824-y PMID: 31767039
Abstract:
Epigenetic clocks comprise a set of CpG sites whose DNA methylation levels measure subject age. These clocks are acknowledged as a highly accurate molecular correlate of chronological age in humans … >>>
Epigenetic clocks comprise a set of CpG sites whose DNA methylation levels measure subject age. These clocks are acknowledged as a highly accurate molecular correlate of chronological age in humans and other vertebrates. Also, extensive research is aimed at their potential to quantify biological aging rates and test longevity or rejuvenating interventions. Here, we discuss key challenges to understand clock mechanisms and biomarker utility. This requires dissecting the drivers and regulators of age-related changes in single-cell, tissue- and disease-specific models, as well as exploring other epigenomic marks, longitudinal and diverse population studies, and non-human models. We also highlight important ethical issues in forensic age determination and predicting the trajectory of biological aging in an individual. <<<
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589.
姗姗来迟 (2022-12-31 17:48):
#paper https://link.springer.com/article/10.1007/s11263-022-01654-0?utm_source=xmol&utm_content=meta PageNet: Towards End-to-End Weakly Supervised Page-Level Handwritten Chinese Text Recognition 该工作针对篇幅级手写中文文本识别问题,提出了端到端弱监督的方法PageNet。该方法的主要优势在于:(1)从一个新的角度解决篇幅级中文文本识别问题——检测识别单字并预测单字间的阅读顺序。(2)模型可以弱监督地训练。对于真实数据仅需要标注文本,不需要任何边界框标注,极大地降低了数据的标注成本。(3)尽管只需要文本标注信息,模型却可以预测出单字级和文本行级的检测和识别结果。(4)该方法深入研究篇幅级文本识别中的阅读顺序问题,所提出的阅读顺序模块可以处理多方向文本、弯曲文本等复杂的阅读顺序。
Abstract:
Handwritten Chinese text recognition (HCTR) has been an active research topic for decades. However, most previous studies solely focus on the recognition of cropped text line images, ignoring the error … >>>
Handwritten Chinese text recognition (HCTR) has been an active research topic for decades. However, most previous studies solely focus on the recognition of cropped text line images, ignoring the error caused by text line detection in real-world applications. Although some approaches aimed at page-level text recognition have been proposed in recent years, they either are limited to simple layouts or require very detailed annotations including expensive line-level and even character-level bounding boxes. To this end, we propose PageNet for end-to-end weakly supervised page-level HCTR. PageNet detects and recognizes characters and predicts the reading order between them, which is more robust and flexible when dealing with complex layouts including multi-directional and curved text lines. Utilizing the proposed weakly supervised learning framework, PageNet requires only transcripts to be annotated for real data; however, it can still output detection and recognition results at both the character and line levels, avoiding the labor and cost of labeling bounding boxes of characters and text lines. Extensive experiments conducted on five datasets demonstrate the superiority of PageNet over existing weakly supervised and fully supervised page-level methods. These experimental results may spark further research beyond the realms of existing methods based on connectionist temporal classification or attention. The source code is available at https://github.com/shannanyinxiang/PageNet. <<<
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590.
DeDe宝 (2022-12-31 17:34):
#paper doi: doi.org/10.1073/pnas.2202394119,Sleep facilitates spatial memory but not navigation using the Minecraft Memory and Navigation tas,PNAS这篇文章是今年10月刚发表的,基于《我的世界》这个游戏分别研究了睡眠对于导航能力、导航记忆的作用。之前的研究已经证实睡眠可以促进海马相关的记忆,而我们知道海马可以支持空间环境的获取和内部表征,也就是海马可以支持认知地图的形成,认知地图是通过环境探索构建的,是导航的重要表征。那么,推出睡眠可以促进导航相关的记忆就是相当自然的。但是,之前的研究者对于睡眠对导航相关空间记忆的作用的研究结果却不乐观,有一些证实了该推测,而有一些没有。本文研究者认为,睡眠对导航相关空间记忆的作用,要拆成睡眠对空间记忆的作用,以及睡眠对导航能力的作用两部分来看。研究结果支持睡眠促进空间记忆,但不能促进导航能力。
Abstract:
Sleep facilitates hippocampal-dependent memories, supporting the acquisition and maintenance of internal representation of spatial relations within an environment. In humans, however, findings have been mixed regarding sleep's contribution to spatial … >>>
Sleep facilitates hippocampal-dependent memories, supporting the acquisition and maintenance of internal representation of spatial relations within an environment. In humans, however, findings have been mixed regarding sleep's contribution to spatial memory and navigation, which may be due to task designs or outcome measurements. We developed the Minecraft Memory and Navigation (MMN) task for the purpose of disentangling how spatial memory accuracy and navigation change over time, and to study sleep's independent contributions to each. In the MMN task, participants learned the locations of objects through free exploration of an open field computerized environment. At test, they were teleported to random positions around the environment and required to navigate to the remembered location of each object. In study 1, we developed and validated four unique MMN environments with the goal of equating baseline learning and immediate test performance. A total of 86 participants were administered the training phases and immediate test. Participants' baseline performance was equivalent across all four environments, supporting the use of the MMN task. In study 2, 29 participants were trained, tested immediately, and again 12 h later after a period of sleep or wake. We found that the metric accuracy of object locations, i.e., spatial memory, was maintained over a night of sleep, while after wake, metric accuracy declined. In contrast, spatial navigation improved over both sleep and wake delays. Our findings support the role of sleep in retaining the precise spatial relationships within a cognitive map; however, they do not support a specific role of sleep in navigation. <<<
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591.
哪有情可长 (2022-12-31 16:21):
#paper MicroTom Metabolic Network: Rewiring Tomato Metabolic Regulatory Network throughout the Growth Cycle,Molecular Plant , August 2020 ,https://doi.org/10.1016/j.molp.2020.06.005. 作者对整个番茄生命周期的根、茎、叶、花、果实进行取样进行转录组和代谢中测序,构建了番茄生长时期的代谢图谱和番茄发育过程的时间天空网络。除了验证前人已经发表过的重要代谢物的调控网络,也鉴定到一个一个转录因子可以调节重要的次级代谢物的合成,黄酮类的代谢物。该文章的模式跟该课题组发水稻的代谢调控网络类似,包括处理方法都是类似(Rice metabolic regulatory network spanning the entire life cycle)。作为植物中进行代谢组和转录组数据联合分析的入门可以精读下。但是内在的代谢物的作用,还是需要一篇篇文献积累。
IF:17.100Q1 Molecular plant, 2020-08-03. DOI: 10.1016/j.molp.2020.06.005 PMID: 32561360
Abstract:
Tomato (Solanum lycopersicum) is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research. Although many research efforts have focused on the analysis of metabolite … >>>
Tomato (Solanum lycopersicum) is a major horticultural crop worldwide and has emerged as a preeminent model for metabolic research. Although many research efforts have focused on the analysis of metabolite differences between varieties and species, the dynamics of metabolic changes during the tomato growth cycle and the regulatory networks that underlie these changes are poorly understood. In this study, we integrated high-resolution spatio-temporal metabolome and transcriptome data to systematically explore the metabolic landscape across 20 major tomato tissues and growth stages. In the resulting MicroTom Metabolic Network, the 540 detected metabolites and their co-expressed genes could be divided into 10 distinct clusters based on their biological functions. Using this dataset, we constructed a global map of the major metabolic changes that occur throughout the tomato growth cycle and dissected the underlying regulatory network. In addition to verifying previously well-established regulatory networks for important metabolites, we identified novel transcription factors that regulate the biosynthesis of important secondary metabolites such as steroidal glycoalkaloids and flavonoids. Our findings provide insights into spatio-temporal changes in tomato metabolism and generate a valuable resource for the study of metabolic regulatory processes in model plants. <<<
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尹志 (2022-12-31 14:48):
#paper doi: https://doi.org/10.48550/arXiv.2210.11250,Structure-based drug design with geometric deep learning. 这是一篇比较新的关于药物设计和深度学习的短小的综述。主要探讨了在结构化药物设计领域的若干重要子任务上,几何深度学习技术是如何发挥其作用的。考虑到结构化药物设计主要使用大分子(比如蛋白质、核酸)的三维几何信息来识别合适的配体,几何深度学习作为一种将几何对称性引入深度学习的技术是非常有潜力的工具。文章主要探讨了1)分子性质预测(结合亲和度、蛋白质功能、位置分数);2)结合位点和结合面预测(小分子结合位点和蛋白-蛋白结合面);3)结合位置生成和分子对接(配体-蛋白和蛋白-蛋白对接);4)基于结构的小分子配体de novo 设计几个子任务。从分子的常见表征谈起,再讨论结构化药物设计中存在的对称性问题,然后通过四个小节,分别讨论了几何深度学习对四个子任务的研究现状。是基于AI的结构化药物设计领域的一篇很不错的guideline。
Abstract:
Structure-based drug design uses three-dimensional geometric information of macromolecules, such as proteins or nucleic acids, to identify suitable ligands. Geometric deep learning, an emerging concept of neural-network-based machine learning, has … >>>
Structure-based drug design uses three-dimensional geometric information of macromolecules, such as proteins or nucleic acids, to identify suitable ligands. Geometric deep learning, an emerging concept of neural-network-based machine learning, has been applied to macromolecular structures. This review provides an overview of the recent applications of geometric deep learning in bioorganic and medicinal chemistry, highlighting its potential for structure-based drug discovery and design. Emphasis is placed on molecular property prediction, ligand binding site and pose prediction, and structure-based de novo molecular design. The current challenges and opportunities are highlighted, and a forecast of the future of geometric deep learning for drug discovery is presented. <<<
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徐炳祥 (2022-12-31 14:45):
#paper doi: 10.1186/s13059-022-02835-3 Genome Biology, 2022, NetAct: a computational platform to construct core transcription factor regulatory networks using gene activity。如何构建基因表达调控网络始终是系统生物学面临的重要课题。当前的基因调控网络构造方法普遍基于基因表达数据,而转录因子的功能往往体现在表达之外;此外,当前常用的基因表达调控网络构建的数学/统计方法擅长关注相关性而非因果性;这些缺陷使得当前对基因调控网络的构造效果不佳。本文从文献整理的转录因子和靶基因数据库出发,借助基因表达数据和GSEA提出了一种新的评估某过程中TF活性的策略。在评估的基础上使用互信息完成了基因表达调控网络的构造。本文中结合数据库中转录因子——靶基因关系和基因表达数据进行的转录因子活性定量方法是值得借鉴的。
IF:10.100Q1 Genome biology, 2022-12-27. DOI: 10.1186/s13059-022-02835-3 PMID: 36575445 PMCID:PMC9793520
Abstract:
A major question in systems biology is how to identify the core gene regulatory circuit that governs the decision-making of a biological process. Here, we develop a computational platform, named … >>>
A major question in systems biology is how to identify the core gene regulatory circuit that governs the decision-making of a biological process. Here, we develop a computational platform, named NetAct, for constructing core transcription factor regulatory networks using both transcriptomics data and literature-based transcription factor-target databases. NetAct robustly infers regulators' activity using target expression, constructs networks based on transcriptional activity, and integrates mathematical modeling for validation. Our in silico benchmark test shows that NetAct outperforms existing algorithms in inferring transcriptional activity and gene networks. We illustrate the application of NetAct to model networks driving TGF-β-induced epithelial-mesenchymal transition and macrophage polarization. <<<
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笑对人生 (2022-12-31 13:24):
#paper doi: 10.1016/j.cell.2021.03.009. Characterizing genetic intra-tumor heterogeneity across 2,658 human cancer genomes. Cell. 2021 Apr 15;184(8):2239-2254.e39. 瘤内异质性(Intra-tumor heterogeneity,ITH)是癌症治疗耐药发生的重要因素之一。ITH的计算其实是首先通过计算突变在所有肿瘤细胞的占比(即CCF),然后将具有相似肿瘤占比的突变进行聚类,最终区分肿瘤组织中哪些细胞是clone,哪些是subclone。因此,ITH的形成与肿瘤组织内clone和subclone的比例密切相关。一般来说,患者ITH低,具有免疫原性的肿瘤新生抗原主要来自clone,那么在经过治疗后,大部分的肿瘤细胞会杀死,患者预后较好。本研究通过对38种癌症类型,共2658份肿瘤组织样本的全基因组测序数据(Whole-genome sequencing,WGS)进行了ITH分析。该分析的数据集来自PCAWG,分析的内容包括单核苷酸变异、插入或缺失、结构变异、拷贝数变异、亚克隆结构推断和进化关系、以及突变特征分析,每种分析使用了4-11种算法。研究发现,大概95.1%的样本在复杂的亚克隆支型进化关系种存在明显的亚克隆扩张。在大多数癌症类型中存在亚克隆驱动突变的正向选择(positive selection)。正向选择通常会引起突变位点的多态性降低,累积有利变异,最终引起selective sweep。Selective sweep就是指当某种有利突变受到强的自然选择后,引起该位点所在染色体区域的基因多态性降低的现象。此外,该研究进一步揭示了亚克隆扩张之间存在具有癌种特异性的驱动基因突变、基因融合、结构变异和拷贝数变异的亚克隆模式,以及一些动态的突变过程。类似的研究在2019年曾有报道 (doi: 10.1038/s41586-019-1689-y),但主要关注肿瘤的转移灶,认为相比于原发肿瘤,转移灶的肿瘤内异质性相对较低。文章中涉及的一些专有名词如下:CCF,cancer cell fraction是指包含某种变异的细胞在所有肿瘤细胞的占比。如果肿瘤组织中所有肿瘤细胞携带某个特定的体细胞突变,那么这个突变的CCF即为1。乘客突变(passenger mutation)指肿瘤的发生和发展无关的突变、与之相对的促进肿瘤发展的驱动突变(driver mutation)。WGD,whole-genome duplication/doubling,全基因组倍增涉及整套染色体复制,可引起所有基因的拷贝增加,是人类肿瘤非整倍体变异进化的主要影响因素。2021年,有研究使用了约10000个原发肿瘤样本,涵盖32种不同肿瘤类型,全面分析了具有WGD的肿瘤基因组特征(doi: 10.1038/s41586-020-03133-3)。
IF:45.500Q1 Cell, 2021. DOI: 10.1016/j.cell.2021.03.009
Stefan C. Dentro , Ignaty Leshchiner , Kerstin Haase , Maxime Tarabichi , Jeff Wintersinger , Amit G. Deshwar , Kaixian Yu , Yulia Rubanova , Geoff Macintyre , Jonas Demeulemeester , Ignacio Vázquez-García , Kortine Kleinheinz , Dimitri G. Livitz , Salem Malikic , Nilgun Donmez , Subhajit Sengupta , Pavana Anur , Clemency Jolly , Marek Cmero , Daniel Rosebrock , Steven E. Schumacher , Yu Fan , Matthew Fittall , Ruben M. Drews , Xiaotong Yao , Thomas B.K. Watkins , Juhee Lee , Matthias Schlesner , Hongtu Zhu , David J. Adams , Nicholas McGranahan , Charles Swanton , Gad Getz , Paul C. Boutros , Marcin Imielinski , Rameen Beroukhim , S. Cenk Sahinalp , Yuan Ji , Martin Peifer , Inigo Martincorena , Florian Markowetz , Ville Mustonen , Ke Yuan , Moritz Gerstung , Paul T. Spellman , Wenyi Wang , Quaid D. Morris , David C. Wedge , Peter Van Loo , Stefan C. Dentro , Ignaty Leshchiner , Moritz Gerstung , Clemency Jolly , Kerstin Haase , Maxime Tarabichi , Jeff Wintersinger , Amit G. Deshwar , Kaixian Yu , Santiago Gonzalez , Yulia Rubanova , Geoff Macintyre , Jonas Demeulemeester , David J. Adams , Pavana Anur , Rameen Beroukhim , Paul C. Boutros , David D. Bowtell , Peter J. Campbell , Shaolong Cao , Elizabeth L. Christie , Marek Cmero , Yupeng Cun , Kevin J. Dawson , Nilgun Donmez , Ruben M. Drews , Roland Eils , Yu Fan , Matthew Fittall , Dale W. Garsed , Gad Getz , Gavin Ha , Marcin Imielinski , Lara Jerman , Yuan Ji , Kortine Kleinheinz , Juhee Lee , Henry Lee-Six , Dimitri G. Livitz , Salem Malikic , Florian Markowetz , Inigo Martincorena , Thomas J. Mitchell , Ville Mustonen , Layla Oesper , Martin Peifer , Myron Peto , Benjamin J. Raphael , Daniel Rosebrock , S. Cenk Sahinalp , Adriana Salcedo , Matthias Schlesner , Steven E. Schumacher , Subhajit Sengupta , Ruian Shi , Seung Jun Shin , Lincoln D. Stein , Oliver Spiro , Ignacio Vázquez-García , Shankar Vembu , David A. Wheeler , Tsun-Po Yang , Xiaotong Yao , Ke Yuan , Hongtu Zhu , Wenyi Wang , Quaid D. Morris , Paul T. Spellman , David C. Wedge , Peter Van Loo <<<
Abstract:
Intra-tumor heterogeneity (ITH) is a mechanism of therapeutic resistance and therefore an important clinical challenge. However, the extent, origin, and drivers of ITH across cancer types are poorly understood. To … >>>
Intra-tumor heterogeneity (ITH) is a mechanism of therapeutic resistance and therefore an important clinical challenge. However, the extent, origin, and drivers of ITH across cancer types are poorly understood. To address this, we extensively characterize ITH across whole-genome sequences of 2,658 cancer samples spanning 38 cancer types. Nearly all informative samples (95.1%) contain evidence of distinct subclonal expansions with frequent branching relationships between subclones. We observe positive selection of subclonal driver mutations across most cancer types and identify cancer type-specific subclonal patterns of driver gene mutations, fusions, structural variants, and copy number alterations as well as dynamic changes in mutational processes between subclonal expansions. Our results underline the importance of ITH and its drivers in tumor evolution and provide a pan-cancer resource of comprehensively annotated subclonal events from whole-genome sequencing data. <<<
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小年 (2022-12-31 13:02):
#paper doi: 10.1038/s41417-021-00418-1. Use of CAR T-cell for acute lymphoblastic leukemia (ALL) treatment: a review study. Cancer Gene Ther. 2022. 急性淋巴细胞白血病(ALL)是一种癌症特异性淋巴细胞。近年来,新的治疗方法得到了广泛的应用。造血干细胞移植(HSCT)存在显着的局限性。虽然可以实现疾病的完全或部分缓解,但复发/难治性(R/R)AML患者的预后较差,移植后复发率高,需要新药物和新方案改善这类患者的长期生存。因此,使用替代方法来解决这些治疗挑战似乎至关重要。在过去十年中,用嵌合抗原受体(CAR)治疗ALL的基因工程T细胞得到了广泛的研究。根据I/II期临床试验,这项技术结果似乎非常有希望,可以在未来用作ALL治疗的有效和安全的治疗方法。 在本综述中,讨论了与嵌合抗原受体(CAR)T细胞用于ALL治疗相关的不同世代,挑战和临床研究,具体通过CAR-T细胞制造和治疗、靶向抗原、临床试验、CAR-T毒性、CAR-T治疗的优势、CAR-T细胞疗法的挑战、克服挑战的策略等方面。文中指出,当前研究和未来调查的核心部分集中在鉴定新的靶标抗原和当前可用靶标的新组合上,一个主要的挑战是选择更好的临床前研究来识别潜在的组合。此外,探索抗原损失机制和确定克服策略对于研究目的至关重要,克服肿瘤微环境中的T细胞功能抑制剂可以加速CAR-T细胞产品的开发和进步。
IF:4.800Q1 Cancer gene therapy, 2022-08. DOI: 10.1038/s41417-021-00418-1 PMID: 34987176
Abstract:
Acute lymphoblastic leukemia (ALL) is a cancer-specific lymphoid cell. Induction and consolidation chemotherapy alone or in combination with different therapeutic approaches remain the main treatment. Although complete or partial remission … >>>
Acute lymphoblastic leukemia (ALL) is a cancer-specific lymphoid cell. Induction and consolidation chemotherapy alone or in combination with different therapeutic approaches remain the main treatment. Although complete or partial remission of the disease can be achieved, the risk of relapse or refractory leukemia is still high. More effective and safe therapy options are yet unmet needs. In recent years' new therapeutic approaches have been widely used. Hematopoietic Stem Cell Transplantation (HSCT) presents significant limitations and the outcome of the consolidation treatment is patient dependent. Side effects such as Graft versus Host Disease (GvHD) in allogeneic hematopoietic stem cell transplantation are extremely common, therefore, using alternative methods to address these challenges for treatment seems crucial. In the last decade, T cells genetically engineered with Chimeric Antigen Receptor (CAR) treatment for the ALL are largely studied and represent the new era of strategy. According to the Phase I/II clinical trials, this technology results seem very promising and can be used in the next future as an effective and safe treatment for ALL treatment. In this review different generations, challenges, and clinical studies related to chimeric antigen receptor (CAR) T-cells for ALL treatment are discussed. <<<
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LXJ (2022-12-31 11:55):
#paper doi: 10.1016/j.it.2022.10.005. Lactic acid and lactate: revisiting the physiological roles in the tumor microenvironment. Trends Immunol. 2022 Dec;43(12):969-977. 这是一篇综述研究,乳酸的产生被认为是恶性细胞逃避免疫监视的一种机制。最近的质谱技术进步和使用具有生理营养成分的细胞培养基,为乳酸及其共轭乳酸在肿瘤微环境中的作用提供了新的视角。本文作者回顾了鉴定乳酸作为哺乳动物肿瘤和免疫细胞的生理碳源的新工作,强调了其作为底物的用途不同于乳酸质子对细胞外环境的免疫抑制酸化的证据。总之,数据表明,应在维持细胞毒性CD8+T细胞生理乳酸代谢的同时,中和肿瘤内酸性的影响,以提高抗肿瘤免疫力。
IF:13.100Q1 Trends in immunology, 2022-12. DOI: 10.1016/j.it.2022.10.005 PMID: 36319537
Abstract:
Lactic acid production has been regarded as a mechanism by which malignant cells escape immunosurveillance. Recent technological advances in mass spectrometry and the use of cell culture media with a … >>>
Lactic acid production has been regarded as a mechanism by which malignant cells escape immunosurveillance. Recent technological advances in mass spectrometry and the use of cell culture media with a physiological nutrient composition have shed new light on the role of lactic acid and its conjugate lactate in the tumor microenvironment. Here, we review novel work identifying lactate as a physiological carbon source for mammalian tumors and immune cells. We highlight evidence that its use as a substrate is distinct from the immunosuppressive acidification of the extracellular milieu by lactic acid protons. Together, data suggest that neutralizing the effects of intratumoral acidity while maintaining physiological lactate metabolism in cytotoxic CD8 T cells should be pursued to boost anti-tumor immunity. <<<
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前进 (2022-12-31 11:39):
#paper Liu Y, Chen J, Wei S, et al. On Finite Difference Jacobian Computation in Deformable Image Registration[J]. arXiv preprint arXiv:2212.06060, 2022. 产生微分同胚的空间变换一直是变形图像配准的中心问题。作为一个微分同胚变换,应在任何位置都具有正的雅可比行列式|J|。|J|<0的体素数已被用于测试微分同胚性,也用于测量变换的不规则性。 对于数字变换,|J|通常使用中心差来近似,但是对于即使在体素分辨率级别上也明显不具有差分同胚性的变换,这种策略可以产生正的|J|。为了证明这一点,论文首先研究了|J|的不同有限差分近似的几何意义。为了确定数字图像的微分同胚性,使用任何单独的有限差分逼近|J|是不够的。论文证明对于2D变换,|J|的四个唯一的有限差分近似必须是正的,以确保整个域是可逆的,并且在像素级没有折叠。在3D中,|J|的十个唯一的有限差分近似值需要是正的。论文提出的数字微分同胚准则解决了|J|的中心差分近似中固有的几个误差,并准确地检测非微分同胚数字变换。
Abstract:
Producing spatial transformations that are diffeomorphic has been a central problem in deformable image registration. As a diffeomorphic transformation should have positive Jacobian determinant |J| everywhere, the number of voxels … >>>
Producing spatial transformations that are diffeomorphic has been a central problem in deformable image registration. As a diffeomorphic transformation should have positive Jacobian determinant |J| everywhere, the number of voxels with |J|<0 has been used to test for diffeomorphism and also to measure the irregularity of the transformation. For digital transformations, |J| is commonly approximated using central difference, but this strategy can yield positive |J|'s for transformations that are clearly not diffeomorphic -- even at the voxel resolution level. To show this, we first investigate the geometric meaning of different finite difference approximations of |J|. We show that to determine diffeomorphism for digital images, use of any individual finite difference approximations of |J| is insufficient. We show that for a 2D transformation, four unique finite difference approximations of |J|'s must be positive to ensure the entire domain is invertible and free of folding at the pixel level. We also show that in 3D, ten unique finite differences approximations of |J|'s are required to be positive. Our proposed digital diffeomorphism criteria solves several errors inherent in the central difference approximation of |J| and accurately detects non-diffeomorphic digital transformations. <<<
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颜林林 (2022-12-30 20:49):
#paper doi:10.1038/s41551-022-00952-9 Nat. Biomed. Eng, 2022, A deep-learning model for transforming the style of tissue images from cryosectioned to formalin-fixed and paraffin-embedded. 在肿瘤诊治过程中,经常需要通过对肿瘤组织进行组织学检查,得到病理诊断结果,才能做出合适的治疗方案。病理组织学检查,需要对组织进行福尔马林固定、石蜡包埋和切片制片,然后将切片放置在显微镜下进行观察,整个过程非常耗时耗力,因而难以应用于手术期间快速决策。冰冻组织切片虽然可以快速进行,但该技术面临细胞结构不容易保留、经常出现各类人为实验因素造成的伪影(artefacts)等挑战,干扰组织学检查过程。本文构建了一个基于GAN的深度学习模型AI-FFPE,用来将冰冻组织切片图像转换成为石蜡包埋组织切片风格,并以此修正各类伪影,提升通过冰冻组织切片来进行组织学检查的效率。经该模型应用于脑肿瘤和肺癌的病理图像公共数据集,进行验证和评估,确实有效修正了相关伪影问题,且效果相对其他专门进行病理图像修正的工具算法更好。此外,本文还将AI-FFPE的输出图像,交给27位病理医生进行人工评估,以及交给之前已发表的AI阅片程序进行分类,其结果也都支持AI-FFPE策略的有效性。
Abstract:
Histological artefacts in cryosectioned tissue can hinder rapid diagnostic assessments during surgery. Formalin-fixed and paraffin-embedded (FFPE) tissue provides higher quality slides, but the process for obtaining them is laborious (typically … >>>
Histological artefacts in cryosectioned tissue can hinder rapid diagnostic assessments during surgery. Formalin-fixed and paraffin-embedded (FFPE) tissue provides higher quality slides, but the process for obtaining them is laborious (typically lasting 12-48 h) and hence unsuitable for intra-operative use. Here we report the development and performance of a deep-learning model that improves the quality of cryosectioned whole-slide images by transforming them into the style of whole-slide FFPE tissue within minutes. The model consists of a generative adversarial network incorporating an attention mechanism that rectifies cryosection artefacts and a self-regularization constraint between the cryosectioned and FFPE images for the preservation of clinically relevant features. Transformed FFPE-style images of gliomas and of non-small-cell lung cancers from a dataset independent from that used to train the model improved the rates of accurate tumour subtyping by pathologists. <<<
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惊鸿 (2022-12-29 15:54):
#paper DOI : 10.1126/science.abl6620 Glassfrogs conceal blood in their liver to maintain transparency 20221222 动物的透明体是一种复杂的伪装形式,涉及减少整个生物体的光散射和吸收的机制。在脊椎动物中,获得透明度很困难,因为它们的循环系统充满了强烈减弱光线的红细胞 (RBC)。在此,这个实验团队记录了玻璃蛙如何通过隐藏这些细胞。该实验团队使用光声成像在体内追踪红细胞,表明静息玻璃蛙通过从循环中去除约 89% 的红细胞并将其包装在肝脏中,从而将透明度提高两到三倍。因此,脊椎动物的透明性需要透明组织和从这些组织中“清除”呼吸色素的活跃机制。此外,玻璃蛙能够调节位置、密度。
Abstract:
Transparency in animals is a complex form of camouflage involving mechanisms that reduce light scattering and absorption throughout the organism. In vertebrates, attaining transparency is difficult because their circulatory system … >>>
Transparency in animals is a complex form of camouflage involving mechanisms that reduce light scattering and absorption throughout the organism. In vertebrates, attaining transparency is difficult because their circulatory system is full of red blood cells (RBCs) that strongly attenuate light. Here, we document how glassfrogs overcome this challenge by concealing these cells from view. Using photoacoustic imaging to track RBCs in vivo, we show that resting glassfrogs increase transparency two- to threefold by removing ~89% of their RBCs from circulation and packing them within their liver. Vertebrate transparency thus requires both see-through tissues and active mechanisms that "clear" respiratory pigments from these tissues. Furthermore, glassfrogs' ability to regulate the location, density, and packing of RBCs without clotting offers insight in metabolic, hemodynamic, and blood-clot research. <<<
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李翛然 (2022-12-28 21:08):
#paper doi:10.1016/S1473-3099(22)00291-2 Respiratory syncytial virus prevention within reach: the vaccine and monoclonal antibody landscape. Lancet Infect Dis. 2022 Aug 8:S1473-3099(22)00291-2. . 这篇文章非常好的梳理了正在北美和欧洲大杀四方的rsv 病毒疫苗研发情况。 现在国门打开,未来必然是新冠+rsv+流感的轮流爆发,我司准备开一个这个管线。这篇综述写的非常好。 很有参考价值的梳理了技术路线,临床阶段,为我们的布局很有指导性意义。
Abstract:
Respiratory syncytial virus is the second most common cause of infant mortality and a major cause of morbidity and mortality in older adults (aged >60 years). Efforts to develop a … >>>
Respiratory syncytial virus is the second most common cause of infant mortality and a major cause of morbidity and mortality in older adults (aged >60 years). Efforts to develop a respiratory syncytial virus vaccine or immunoprophylaxis remain highly active. 33 respiratory syncytial virus prevention candidates are in clinical development using six different approaches: recombinant vector, subunit, particle-based, live attenuated, chimeric, and nucleic acid vaccines; and monoclonal antibodies. Nine candidates are in phase 3 clinical trials. Understanding the epitopes targeted by highly neutralising antibodies has resulted in a shift from empirical to rational and structure-based vaccine and monoclonal antibody design. An extended half-life monoclonal antibody for all infants is likely to be within 1 year of regulatory approval (from August, 2022) for high-income countries. Live-attenuated vaccines are in development for older infants (aged >6 months). Subunit vaccines are in late-stage trials for pregnant women to protect infants, whereas vector, subunit, and nucleic acid approaches are being developed for older adults. Urgent next steps include ensuring access and affordability of a respiratory syncytial virus vaccine globally. This review gives an overview of respiratory syncytial virus vaccines and monoclonal antibodies in clinical development highlighting different target populations, antigens, and trial results. <<<
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