当前共找到 1189 篇文献分享,本页显示第 581 - 600 篇。
581.
Spring (2023-03-31 13:10):
#paper doi: 10.15252/emmm.202317450 EMBO Molecular Medicine[IF:14.26] ① 纳入两个独立的队列人群,比较了早发性卵巢功能不全(POI)女性血清代谢组学,发现其表现为支链氨基酸(BCAA)不足相关的代谢紊乱;② 在小鼠模型中,低BCAA饮食干预使年轻小鼠出现POI样的代谢、内分泌、卵巢和生殖变化;③ 细胞实验表明,BCAA不足会上调神经酰胺,诱导ROS升高,从而使卵巢颗粒细胞功能受损;④ 有趣的是,BCAA膳食补充可以阻止雌性小鼠ROS诱导的POI发展,提示其预防价值。 BCAA insufficiency leads to premature ovarian insufficiency via ceramide-induced elevation of ROS
IF:9.000Q1 EMBO molecular medicine, 2023-04-11. DOI: 10.15252/emmm.202317450 PMID: 36847712
Abstract:
Premature ovarian insufficiency (POI) is a disease featured by early menopause before 40 years of age, accompanied by an elevation of follicle-stimulating hormone. Though POI affects many aspects of women's … >>>
Premature ovarian insufficiency (POI) is a disease featured by early menopause before 40 years of age, accompanied by an elevation of follicle-stimulating hormone. Though POI affects many aspects of women's health, its major causes remain unknown. Many clinical studies have shown that POI patients are generally underweight, indicating a potential correlation between POI and metabolic disorders. To understand the pathogenesis of POI, we performed metabolomics analysis on serum and identified branch-chain amino acid (BCAA) insufficiency-related metabolic disorders in two independent cohorts from two clinics. A low BCAA diet phenotypically reproduced the metabolic, endocrine, ovarian, and reproductive changes of POI in young C57BL/6J mice. A mechanism study revealed that the BCAA insufficiency-induced POI is associated with abnormal activation of the ceramide-reactive oxygen species (ROS) axis and consequent impairment of ovarian granulosa cell function. Significantly, the dietary supplement of BCAA prevented the development of ROS-induced POI in female mice. The results of this pathogenic study will lead to the development of specific therapies for POI. <<<
翻译
582.
尹志 (2023-03-31 00:12):
#paper https://doi.org/10.1038/s41586-023-05870-7. Nature, 2023, Programmable protein delivery with a bacterial contractile injection system。这是今年张锋组的一篇新文章。文章介绍了一种叫做外胞质收缩注射系统(eCISs)的纳米机器,它们可以被重新编程以针对人类细胞并传递各种蛋白质负载,包括Cas9、碱基编辑器和毒素。这些系统可以用于基因治疗、癌症治疗和生物控制等领域。还讨论了利用收缩注射系统(CIS)作为蛋白质传递和基因编辑的潜在工具以及它们在生物技术和医学中的应用。基本都是实验,方法部分简直大开眼界,琳琅满目,基本看不懂;但看结论还是觉得挺有前瞻性的工作,而且使用了AF技术作为structure-guided engineering,这个很引起我的兴趣。总之,先浅浅仰慕读一下
IF:50.500Q1 Nature, 2023-04. DOI: 10.1038/s41586-023-05870-7 PMID: 36991127
Abstract:
Endosymbiotic bacteria have evolved intricate delivery systems that enable these organisms to interface with host biology. One example, the extracellular contractile injection systems (eCISs), are syringe-like macromolecular complexes that inject … >>>
Endosymbiotic bacteria have evolved intricate delivery systems that enable these organisms to interface with host biology. One example, the extracellular contractile injection systems (eCISs), are syringe-like macromolecular complexes that inject protein payloads into eukaryotic cells by driving a spike through the cellular membrane. Recently, eCISs have been found to target mouse cells, raising the possibility that these systems could be harnessed for therapeutic protein delivery. However, whether eCISs can function in human cells remains unknown, and the mechanism by which these systems recognize target cells is poorly understood. Here we show that target selection by the Photorhabdus virulence cassette (PVC)-an eCIS from the entomopathogenic bacterium Photorhabdus asymbiotica-is mediated by specific recognition of a target receptor by a distal binding element of the PVC tail fibre. Furthermore, using in silico structure-guided engineering of the tail fibre, we show that PVCs can be reprogrammed to target organisms not natively targeted by these systems-including human cells and mice-with efficiencies approaching 100%. Finally, we show that PVCs can load diverse protein payloads, including Cas9, base editors and toxins, and can functionally deliver them into human cells. Our results demonstrate that PVCs are programmable protein delivery devices with possible applications in gene therapy, cancer therapy and biocontrol. <<<
翻译
583.
白鸟 (2023-03-30 17:22):
#paper https://www.cell.com/cell/fulltext/S0092-8674(21)01381-7. Differential pre-malignant programs and microenvironment chart distinct paths to malignancy in human colorectal polyps. 此文是人类肿瘤图谱网络(HTAN)联盟两年多时间在CRC肿瘤领域发的2篇cell文章之一,另一篇文章是构建肿瘤空间3D图谱。该联盟的愿景是构建肿瘤的发生、局部扩张、转移和治疗性耐药的动态3D图谱。该文章的切入点很重要,通过已有文献猜想两条CRC癌变的不同机制,提出了一个整合了单细胞转录组学、基因组学和免疫组织病理学的多组学人类癌前图谱。从功能上验证了建立不同的肿瘤景观的不同起源和分子机制过程。也是该联盟的策略从病变起源来研究,才能对晚期和高度异质性的癌症有更清晰的认识,从而为精准预防、监测和治疗的新策略铺平道路。对于多组学文章,切入点(科学猜想)和策略很重要。
IF:45.500Q1 Cell, 2021-12-22. DOI: 10.1016/j.cell.2021.11.031 PMID: 34910928
Abstract:
Colorectal cancers (CRCs) arise from precursor polyps whose cellular origins, molecular heterogeneity, and immunogenic potential may reveal diagnostic and therapeutic insights when analyzed at high resolution. We present a single-cell … >>>
Colorectal cancers (CRCs) arise from precursor polyps whose cellular origins, molecular heterogeneity, and immunogenic potential may reveal diagnostic and therapeutic insights when analyzed at high resolution. We present a single-cell transcriptomic and imaging atlas of the two most common human colorectal polyps, conventional adenomas and serrated polyps, and their resulting CRC counterparts. Integrative analysis of 128 datasets from 62 participants reveals adenomas arise from WNT-driven expansion of stem cells, while serrated polyps derive from differentiated cells through gastric metaplasia. Metaplasia-associated damage is coupled to a cytotoxic immune microenvironment preceding hypermutation, driven partly by antigen-presentation differences associated with tumor cell-differentiation status. Microsatellite unstable CRCs contain distinct non-metaplastic regions where tumor cells acquire stem cell properties and cytotoxic immune cells are depleted. Our multi-omic atlas provides insights into malignant progression of colorectal polyps and their microenvironment, serving as a framework for precision surveillance and prevention of CRC. <<<
翻译
584.
徐炳祥 (2023-03-30 13:13):
#paper doi: 10.1101/gad.333708.119. Genes Dev, 2020, Upon microbial challenge, human neutrophils undergo rapid changes in nuclear architecture and chromatin folding to orchestrate an immediate inflammatory gene program。中性粒细胞免疫应答过程中伴随着核型和染色质构象的剧烈变化,这些变化与免疫应答诱导的转录调控过程之间的关系尚不清楚。本文使用人类中性粒细胞为实验材料,以PMA和大肠杆菌为刺激源诱发免疫反应,以Hi-C测定应答前后的染色质空间构象并进行比较。结果显示,应答之前,炎性基因处于转录抑制的空间构象中,应答后这些基因所在区域发生常染色质化,由核周进入核内部,并与增强子靠近,这些过程与应答过程中转录的快速响应有关。这些染色质构象的重排可能是由cohesin驱动的。本研究处理时长已达3h,但仍未见染色质构象的大范围改变。这些结论提示虽然染色质构象的全基因组重构是罕见事件,其局部的改变依然有研究的价值。
IF:7.500Q1 Genes & development, 2020-02-01. DOI: 10.1101/gad.333708.119 PMID: 31919189
Abstract:
Differentiating neutrophils undergo large-scale changes in nuclear morphology. How such alterations in structure are established and modulated upon exposure to microbial agents is largely unknown. Here, we found that prior … >>>
Differentiating neutrophils undergo large-scale changes in nuclear morphology. How such alterations in structure are established and modulated upon exposure to microbial agents is largely unknown. Here, we found that prior to encounter with bacteria, an armamentarium of inflammatory genes was positioned in a transcriptionally passive environment suppressing premature transcriptional activation. Upon microbial exposure, however, human neutrophils rapidly (<3 h) repositioned the ensemble of proinflammatory genes toward the transcriptionally permissive compartment. We show that the repositioning of genes was closely associated with the swift recruitment of cohesin across the inflammatory enhancer landscape, permitting an immediate transcriptional response upon bacterial exposure. We found that activated enhancers, marked by increased deposition of H3K27Ac, were highly enriched for cistromic elements associated with PU.1, CEBPB, TFE3, JUN, and FOSL2 occupancy. These data reveal how upon microbial challenge the cohesin machinery is recruited to an activated enhancer repertoire to instruct changes in chromatin folding, nuclear architecture, and to activate an inflammatory gene program. <<<
翻译
585.
符毓 Yu (2023-03-30 12:59):
#paper doi:10.1016/j.joule.2020.07.014, Joule, 2020, Ultrasonic Scanning to Observe Wetting and “Unwetting” in Li-Ion Pouch Cells。锂电池的非破坏性检测方式较少见,X射线检测在电极材料结构、尺寸和热机械效应等有应用,但对于电解质和内部气体不敏感;本文主要探讨用超声方式进行检测的可行性
IF:38.600Q1 Joule, 2020. DOI: 10.1016/j.joule.2020.07.014
Abstract:
An ultrasonic imaging technique has been developed to investigate the internal changes of pouch cells nondestructively. The local ultrasonic transmittance of pouch cells has been measured and used for imaging … >>>
An ultrasonic imaging technique has been developed to investigate the internal changes of pouch cells nondestructively. The local ultrasonic transmittance of pouch cells has been measured and used for imaging with a new ultrasonic scanning machine designed and built in-house. The wetting process of the cells is clearly observed via such ultrasonic imaging techniques. Furthermore, ultrasonic transmission images of fresh cells and aged cells with different electrolytes and cycling conditions exhibit very different ultrasonic transmittance, which can be caused by electrolyte dry-out or “unwetting” due to cell swelling. The ultrasonic imaging technique is a very sensitive method to probe failure mechanisms in Li-ion pouch cells. <<<
翻译
586.
李翛然 (2023-03-28 21:41):
#paper A novel protein RASON encoded by a lncRNA controls oncogenic RAS signaling in KRAS mutant cancers doi: 10.1038/s41422-022-00726-7. Cell Research . 这篇文章是我最近精读的一篇文章,作者我都认识,做的靶点恰恰是我们正在做的。所以聊了很多。 这是很有可能针对未来一个大癌症种类的核心解决方案。 只不过现在rason 的结构还没有解析出来。 我们看看今年怎么处理一下。
IF:28.100Q1 Cell research, 2023-01. DOI: 10.1038/s41422-022-00726-7 PMID: 36241718
Abstract:
Mutations of the RAS oncogene are found in around 30% of all human cancers yet direct targeting of RAS is still considered clinically impractical except for the KRAS mutant. Here … >>>
Mutations of the RAS oncogene are found in around 30% of all human cancers yet direct targeting of RAS is still considered clinically impractical except for the KRAS mutant. Here we report that RAS-ON (RASON), a novel protein encoded by the long intergenic non-protein coding RNA 00673 (LINC00673), is a positive regulator of oncogenic RAS signaling. RASON is aberrantly overexpressed in pancreatic ductal adenocarcinoma (PDAC) patients, and it promotes proliferation of human PDAC cell lines in vitro and tumor growth in vivo. CRISPR/Cas9-mediated knockout of Rason in mouse embryonic fibroblasts inhibits KRAS-mediated tumor transformation. Genetic deletion of Rason abolishes oncogenic KRAS-driven pancreatic and lung cancer tumorigenesis in LSL-Kras; Trp53 mice. Mechanistically, RASON directly binds to KRAS and inhibits both intrinsic and GTPase activating protein (GAP)-mediated GTP hydrolysis, thus sustaining KRAS in the GTP-bound hyperactive state. Therapeutically, deprivation of RASON sensitizes KRAS mutant pancreatic cancer cells and patient-derived organoids to EGFR inhibitors. Our findings identify RASON as a critical regulator of oncogenic KRAS signaling and a promising therapeutic target for KRAS mutant cancers. <<<
翻译
587.
姗姗来迟 (2023-03-27 15:44):
#paper arXiv:2201.11903 chain of thought Prompting elicits reasoning in large language models 阅读笔记被记录在本人的博文中:https://blog.csdn.net/weixin_44845357/article/details/129566376 主要是了解思维链(通过逐步回答示例来引出复杂的多步推理的技术)
arXiv, 2022.
Abstract:
We explore how generating a chain of thought -- a series of intermediate reasoning steps -- significantly improves the ability of large language models to perform complex reasoning. In particular, … >>>
We explore how generating a chain of thought -- a series of intermediate reasoning steps -- significantly improves the ability of large language models to perform complex reasoning. In particular, we show how such reasoning abilities emerge naturally in sufficiently large language models via a simple method called chain of thought prompting, where a few chain of thought demonstrations are provided as exemplars in prompting. Experiments on three large language models show that chain of thought prompting improves performance on a range of arithmetic, commonsense, and symbolic reasoning tasks. The empirical gains can be striking. For instance, prompting a 540B-parameter language model with just eight chain of thought exemplars achieves state of the art accuracy on the GSM8K benchmark of math word problems, surpassing even finetuned GPT-3 with a verifier. <<<
翻译
588.
张浩彬 (2023-03-27 15:40):
#paper 10.1109/ijcnn52387.2021.9533426 Self-Supervised Pre-training for Time Series Classification 少有的时间序列迁移学习文章,利用DTW计算距离建立代理任务构建正负样本来做学习,encoder用的transformer,新意少了点。
Abstract:
Recently, significant progress has been made in time series classification with deep learning. However, using deep learning models to solve time series classification generally suffers from expensive calculations and difficulty … >>>
Recently, significant progress has been made in time series classification with deep learning. However, using deep learning models to solve time series classification generally suffers from expensive calculations and difficulty of data labeling. In this work, we study self-supervised time series pre-training to overcome these challenges. Compared with the existing works, we focus on the universal and unlabeled time series pretraining. To this end, we propose a novel end-to-end neural network architecture based on self-attention, which is suitable for capturing long-term dependencies and extracting features from different time series. Then, we propose two different self-supervised pretext tasks for time series data type: Denoising and Similarity Discrimination based on DTW (Dynamic Time Warping). Finally, we carry out extensive experiments on 85 time series datasets (also known as UCR2015 [2]). Empirical results show that the time series model augmented with our proposed self-supervised pretext tasks achieves state-of-the-art / highly competitive results. <<<
翻译
589.
惊鸿 (2023-03-27 11:42):
#paper doi:https://ma.x-mol.com/paperRedirect/1639426668090503168 Thymidine nucleotide metabolism controls human telomere length 人类的端粒长度与寿命和严重疾病有关,但端粒长度的遗传决定因素仍未完全确定。在这里,我们进行了全基因组 CRISPR-Cas9 功能性端粒长度筛选,并将胸苷 (dT) 核苷酸代谢确定为人类端粒维持的限制因素。使用 CRISPR-Cas9 的靶向基因破坏揭示了胸苷核苷酸代谢途径中的多个端粒长度控制点:通过删除编码核胸苷激酶 ( TK1 ) 的基因减少 dT 核苷酸回收或通过敲除胸苷酸合酶基因 (TYMS )从头产生端粒长度减少,而脱氧核苷三磷酸水解酶编码基因SAMHD1失活延长的端粒。值得注意的是,单独补充 dT 可通过细胞中的端粒酶驱动端粒的稳健延伸,并且三磷酸胸苷在体外以底物非依赖性方式刺激端粒酶活性。在源自遗传性端粒生物学障碍患者的诱导多能干细胞中,补充 dT 或抑制SAMHD1可促进端粒恢复。我们的结果表明胸苷代谢在控制人端粒酶和端粒长度方面的关键作用,这可能对致命的退行性疾病患者具有治疗作用。
IF:31.700Q1 Nature genetics, 2023-04. DOI: 10.1038/s41588-023-01339-5 PMID: 36959362
Abstract:
Telomere length in humans is associated with lifespan and severe diseases, yet the genetic determinants of telomere length remain incompletely defined. Here we performed genome-wide CRISPR-Cas9 functional telomere length screening … >>>
Telomere length in humans is associated with lifespan and severe diseases, yet the genetic determinants of telomere length remain incompletely defined. Here we performed genome-wide CRISPR-Cas9 functional telomere length screening and identified thymidine (dT) nucleotide metabolism as a limiting factor in human telomere maintenance. Targeted genetic disruption using CRISPR-Cas9 revealed multiple telomere length control points across the thymidine nucleotide metabolism pathway: decreasing dT nucleotide salvage via deletion of the gene encoding nuclear thymidine kinase (TK1) or de novo production by knockout of the thymidylate synthase gene (TYMS) decreased telomere length, whereas inactivation of the deoxynucleoside triphosphohydrolase-encoding gene SAMHD1 lengthened telomeres. Remarkably, supplementation with dT alone drove robust telomere elongation by telomerase in cells, and thymidine triphosphate stimulated telomerase activity in a substrate-independent manner in vitro. In induced pluripotent stem cells derived from patients with genetic telomere biology disorders, dT supplementation or inhibition of SAMHD1 promoted telomere restoration. Our results demonstrate a critical role of thymidine metabolism in controlling human telomerase and telomere length, which may be therapeutically actionable in patients with fatal degenerative diseases. <<<
翻译
590.
周周复始 (2023-03-27 11:08):
#paper doi:https://doi.org/10.1038/s41596-023-00806-x. iBEAT V2.0: a multisite-applicable, deep learning-based pipeline for infant cerebral cortical surface reconstruction.2023.为了研究正常和异常的早期大脑发育,用不同的扫描仪和成像方案从多个站点收集了许多婴儿大脑磁共振成像(MRI)。但利用这些多站点成像数据精确地处理和量化婴儿的大脑发育是极具挑战性的,因为髓鞘持续形成和成熟而导致的极低和动态的组织对比,以及由于使用不同的成像协议/扫描仪而导致的不同站点间的数据异质性。现有的计算工具和pipeline通常在婴儿MRI数据上表现不佳。为了解决这些挑战,本文提出了一个鲁棒的、多站点适用的、婴儿定制的计算pipeline,它利用强大的深度学习技术。主要功能包括预处理、脑颅骨剥离、组织分割、拓扑校正、皮层表面表面重建和测量。可以很好地处理T1w和大范围(从出生到6岁)的婴儿大脑结构MRI,并且对不同成像协议/扫描仪差异是有效的,尽管只在BCP上训练。在多站点、多模态和多年龄数据集上与现有方法进行了广泛的比较证明ibeat具有优越的有效性、准确性和鲁棒性。
IF:13.100Q1 Nature protocols, 2023-05. DOI: 10.1038/s41596-023-00806-x PMID: 36869216
Abstract:
The human cerebral cortex undergoes dramatic and critical development during early postnatal stages. Benefiting from advances in neuroimaging, many infant brain magnetic resonance imaging (MRI) datasets have been collected from … >>>
The human cerebral cortex undergoes dramatic and critical development during early postnatal stages. Benefiting from advances in neuroimaging, many infant brain magnetic resonance imaging (MRI) datasets have been collected from multiple imaging sites with different scanners and imaging protocols for the investigation of normal and abnormal early brain development. However, it is extremely challenging to precisely process and quantify infant brain development with these multisite imaging data because infant brain MRI scans exhibit (a) extremely low and dynamic tissue contrast caused by ongoing myelination and maturation and (b) inter-site data heterogeneity resulting from the use of diverse imaging protocols/scanners. Consequently, existing computational tools and pipelines typically perform poorly on infant MRI data. To address these challenges, we propose a robust, multisite-applicable, infant-tailored computational pipeline that leverages powerful deep learning techniques. The main functionality of the proposed pipeline includes preprocessing, brain skull stripping, tissue segmentation, topology correction, cortical surface reconstruction and measurement. Our pipeline can handle both T1w and T2w structural infant brain MR images well in a wide age range (from birth to 6 years of age) and is effective for different imaging protocols/scanners, despite being trained only on the data from the Baby Connectome Project. Extensive comparisons with existing methods on multisite, multimodal and multi-age datasets demonstrate superior effectiveness, accuracy and robustness of our pipeline. We have maintained a website, iBEAT Cloud, for users to process their images with our pipeline ( http://www.ibeat.cloud ), which has successfully processed over 16,000 infant MRI scans from more than 100 institutions with various imaging protocols/scanners. <<<
翻译
591.
哪有情可长 (2023-03-24 21:51):
#paper A Gg protein regulates alkaline sensitivity in crops,science,24 march,2023,doi.org/10.1126/science.ade8416. 为了增加粮食产量,利用盐碱地,培养抗盐碱的作物,实现废田利用是现在作物育种的一大趋势。谢旗团队利用高粱这个抗碱性材料来挖掘基因。首先是通过GWAS鉴定到一个跟水稻中同源的基因(GS3)并命名为AT1(Alkaline tolerance 1),对部分高粱品种测序发现该基因能够分成两个单倍型,发现这个基因能够编码非典型G蛋白γ亚基,通过实验证明该基因能够调节环境胁迫下产生的过氧化氢外流,降低碱性敏感性。并且对该基因在小麦,玉米,水稻等作物中都进行大田试验验证,的确能够抗盐碱。
Abstract:
The use of alkaline salt lands for crop production is hindered by a scarcity of knowledge and breeding efforts for plant alkaline tolerance. Through genome association analysis of sorghum, a … >>>
The use of alkaline salt lands for crop production is hindered by a scarcity of knowledge and breeding efforts for plant alkaline tolerance. Through genome association analysis of sorghum, a naturally high-alkaline-tolerant crop, we detected a major locus, (), specifically related to alkaline-salinity sensitivity. An allele with a carboxyl-terminal truncation increased sensitivity, whereas knockout of increased tolerance to alkalinity in sorghum, millet, rice, and maize. encodes an atypical G protein γ subunit that affects the phosphorylation of aquaporins to modulate the distribution of hydrogen peroxide (HO) These processes appear to protect plants against oxidative stress by alkali. Designing knockouts of homologs or selecting its natural nonfunctional alleles could improve crop productivity in sodic lands. <<<
翻译
592.
DeDe宝 (2023-03-22 11:38):
#paper doi: https://doi.org/10.1111/psyp.14270 Wrinkles in subsecond time perception are synchronized to the heart 心脏在时间知觉中的作用的证据很少,本研究探究了心脏动力学和亚秒级别时间间隔感知之间的相互作用。被试根据与心脏同步的音调做时间二分法任务,结果显示颞叶对时间间隔感知的延长或缩短与心脏动力学同步。较低的刺激前心理与较长的编码偏差相关。本研究开发了心脏漂移模型(cDDM),为心脏在时间感知觉判断中的作用提供了新的方法论。
IF:2.900Q1 Psychophysiology, 2023-08. DOI: 10.1111/psyp.14270 PMID: 36864822
Abstract:
The role of the heart in the experience of time has been long theorized but empirical evidence is scarce. Here, we examined the interaction between fine-grained cardiac dynamics and the … >>>
The role of the heart in the experience of time has been long theorized but empirical evidence is scarce. Here, we examined the interaction between fine-grained cardiac dynamics and the momentary experience of subsecond intervals. Participants performed a temporal bisection task for brief tones (80-188 ms) synchronized with the heart. We developed a cardiac Drift-Diffusion Model (cDDM) that embedded contemporaneous heart rate dynamics into the temporal decision model. Results revealed the existence of temporal wrinkles-dilation or contraction of short intervals-in synchrony with cardiac dynamics. A lower prestimulus heart rate was associated with an initial bias in encoding the millisecond-level stimulus duration as longer, consistent with facilitation of sensory intake. Concurrently, a higher prestimulus heart rate aided more consistent and faster temporal judgments through more efficient evidence accumulation. Additionally, a higher speed of poststimulus cardiac deceleration, a bodily marker of attention, was associated with a greater accumulation of sensory temporal evidence in the cDDM. These findings suggest a unique role of cardiac dynamics in the momentary experience of time. Our cDDM framework opens a new methodological avenue for investigating the role of the heart in time perception and perceptual judgment. <<<
翻译
593.
张德祥 (2023-03-20 10:45):
#paper doi: https://doi.org/10.1101/2022.05.17.492325 Inferring Neural Activity Before Plasticity: A Foundation for Learning Beyond Backpropagation 超越GPT需要从更底层的技术改进,BP是深度学习的核心,生物算法比BP更高效,生物算法是超越BP的一个途径,这篇论文给出了很好的解释及后续论文有一些实验及算法,效率已经可以匹配BP,仍然有更多的优点, 更多可以参考 https://mp.weixin.qq.com/s/lPzGvY6oOnwzVgxDr9ePpA
Abstract:
AbstractFor both humans and machines, the essence of learning is to pinpoint which components in its information processing pipeline are responsible for an error in its output — a challenge … >>>
AbstractFor both humans and machines, the essence of learning is to pinpoint which components in its information processing pipeline are responsible for an error in its output — a challenge that is known ascredit assignment. How the brain solves credit assignment is a key question in neuroscience, and also of significant importance for artificial intelligence. It has long been assumed that credit assignment is best solved by backpropagation, which is also the foundation of modern machine learning. However, it has been questioned whether it is possible for the brain to implement backpropagation and learning in the brain may actually be more efficient and effective than backpropagation. Here, we set out a fundamentally different principle on credit assignment, calledprospective configuration. In prospective configuration, the network first infers the pattern of neural activity that should result from learning, and then the synaptic weights are modified to consolidate the change in neural activity. We demonstrate that this distinct mechanism, in contrast to backpropagation, (1) underlies learning in a well-established family of models of cortical circuits, (2) enables learning that is more efficient and effective in many contexts faced by biological organisms, and (3) reproduces surprising patterns of neural activity and behaviour observed in diverse human and animal learning experiments. Our findings establish a new foundation for learning beyond backpropagation, for both understanding biological learning and building artificial intelligence. <<<
翻译
594.
龙海晨 (2023-03-16 18:02):
#paper Yan Y, Ma Z, Ji X, Liu J, Ji K, Li S, Wu Q. A potential decision-making algorithm based on endoscopic ultrasound for staging early gastric cancer: a retrospective study. BMC Cancer. 2022 Jul 13;22(1):761. doi: 10.1186/s12885-022-09870-0. PMID: 35831843; PMCID: PMC9281103. 文章是研究内镜超声分析所得到的图像与胃癌早期分型间的关系,通过研究影像中肿瘤位置,是否胃溃疡,分化程度,肿瘤大小等指标,建立相关的算法,计算肿瘤分期,确定相应的治疗方案。为早期胃癌诊断治疗提供了一种决策算法。
IF:3.400Q2 BMC cancer, 2022-Jul-13. DOI: 10.1186/s12885-022-09870-0 PMID: 35831843
Abstract:
BACKGROUND: Clinical staging of gastric cancer (GC) before treatment is essential. Endoscopic ultrasound (EUS) is a recommended staging tool, but its efficacy remains controversial. Our previous prospective study evaluated the … >>>
BACKGROUND: Clinical staging of gastric cancer (GC) before treatment is essential. Endoscopic ultrasound (EUS) is a recommended staging tool, but its efficacy remains controversial. Our previous prospective study evaluated the potential value of EUS for T staging and presented discrepancies. In this study, we aimed to evaluate the efficacy of EUS in T staging by comparing it with pathological staging. We analyze the factors that can potentially affect accuracy to identify suitable subgroups for EUS staging.METHODS: Data from a total of 1763 consecutive patients with GC from January 2015 to December 2017 were analyzed. Results from EUS and pathological T staging were compared. The factors that might affect EUS's accuracy were analyzed.RESULTS: The sensitivity, specificity, positive predictive value, and negative predictive value of EUS in patients with early GC were 62.08%, 96.13%, 90.94%, and 80.21%, respectively. The accuracy rates of uT1, uT2-uT4, and uT3-uT4 were 90.94%, 79.02%, and 78.39%, respectively. In multivariate analysis, underestimation was more likely to be observed in patients with tumors located in the middle or upper third of the stomach. Overestimation was more likely to be observed in patients with tumors located in the lower third or those without ulcer. Other factors affecting accuracy included ulcer, differentiation, larger size and undergoing surgery.CONCLUSION: Our findings highlight the role of EUS in determining the T staging of GC. Overestimation and underestimation in T-staging were significantly associated with the tumor location in early GC, and a decision-making algorithm was proposed for clinical practice in early cancers based on these findings. <<<
翻译
595.
颜林林 (2023-03-12 15:29):
#paper doi:10.1016/j.celrep.2023.112230 Cell Reports, 2023, FAM193A is a positive regulator of p53 activity. 这是一篇典型的关于药物敏感机制探索的细胞学研究,通过分子细胞生物学方法和高通量筛选技术,找到一个新调控基因,并确认其功能。癌症研究中最著名的基因当属TP53(其蛋白则称为p53),这是个抑癌基因,在癌组织中常表现出发生突变或被异常调控。针对其抑制型调控蛋白(如MDM2和MDM4),设计的化合物抑制剂,可激活或促进p53功能,进而达到治疗癌症的目的。Nutlin正是这样的候选药物分子。然而Nutlin在不同细胞系或患者中的表现却差异巨大,其作用机制尚待深入研究。这篇论文通过对药物敏感数据库的分析,以及采用CRISPR screening技术,在多个不同细胞系中进行高通量筛选,识别出FAM193A蛋白,其与Nutlin药物敏感性密切相关,并通过一系列证据,证明FAM193A在p53通路中起到正向调节作用,为后续机制研究和药物开发提供了新的方向。
IF:7.500Q1 Cell reports, 2023-03-28. DOI: 10.1016/j.celrep.2023.112230 PMID: 36897777
Abstract:
Inactivation of the p53 tumor suppressor, either by mutations or through hyperactivation of repressors such as MDM2 and MDM4, is a hallmark of cancer. Although many inhibitors of the p53-MDM2/4 … >>>
Inactivation of the p53 tumor suppressor, either by mutations or through hyperactivation of repressors such as MDM2 and MDM4, is a hallmark of cancer. Although many inhibitors of the p53-MDM2/4 interaction have been developed, such as Nutlin, their therapeutic value is limited by highly heterogeneous cellular responses. We report here a multi-omics investigation of the cellular response to MDM2/4 inhibitors, leading to identification of FAM193A as a widespread regulator of p53 function. CRISPR screening identified FAM193A as necessary for the response to Nutlin. FAM193A expression correlates with Nutlin sensitivity across hundreds of cell lines. Furthermore, genetic codependency data highlight FAM193A as a component of the p53 pathway across diverse tumor types. Mechanistically, FAM193A interacts with MDM4, and FAM193A depletion stabilizes MDM4 and inhibits the p53 transcriptional program. Last, FAM193A expression is associated with better prognosis in multiple malignancies. Altogether, these results identify FAM193A as a positive regulator of p53. <<<
翻译
596.
张德祥 (2023-03-12 09:48):
#paper https://doi.org/10.48550/arXiv.1806.08053 Semantic information, autonomous agency, and nonequilibrium statistical physics 论文尝试通过反事实对语义信息进行定义,通过个体跟环境的物理系,热力学的信息交换来实现,但后续工作不多,和自由能框架有些接近,
Abstract:
Shannon information theory provides various measures of so-called "syntactic information", which reflect the amount of statistical correlation between systems. In contrast, the concept of "semantic information" refers to those correlations … >>>
Shannon information theory provides various measures of so-called "syntactic information", which reflect the amount of statistical correlation between systems. In contrast, the concept of "semantic information" refers to those correlations which carry significance or "meaning" for a given system. Semantic information plays an important role in many fields, including biology, cognitive science, and philosophy, and there has been a long-standing interest in formulating a broadly applicable and formal theory of semantic information. In this paper we introduce such a theory. We define semantic information as the syntactic information that a physical system has about its environment which is causally necessary for the system to maintain its own existence. "Causal necessity" is defined in terms of counter-factual interventions which scramble correlations between the system and its environment, while "maintaining existence" is defined in terms of the system's ability to keep itself in a low entropy state. We also use recent results in nonequilibrium statistical physics to analyze semantic information from a thermodynamic point of view. Our framework is grounded in the intrinsic dynamics of a system coupled to an environment, and is applicable to any physical system, living or otherwise. It leads to formal definitions of several concepts that have been intuitively understood to be related to semantic information, including "value of information", "semantic content", and "agency". <<<
翻译
597.
颜林林 (2023-03-02 07:38):
#paper doi:10.1016/j.csbj.2023.02.016 Computational and Structural Biotechnology Journal, 2023, DNAsmart: Multiple attribute ranking tool for DNA data storage systems. 将DNA用作存储介质,已经逐渐成为一个热门的研究方向。由于DNA在读取(测序)和写入(合成)过程中,受到其自身特性和其他环境体系不同因素的影响,存在各类错误。这篇研究提供了一个网站工具DNAsmart,以交互式的方式,可视化地展示核酸片段之间诸如GC含量、汉明距离等不同属性,帮助研究者探索如何有效利用和平衡这些属性的影响,以设计出更合适的DNA存储的编解码方案。
Abstract:
In an ever-growing need for data storage capacity, the Deoxyribonucleic Acid (DNA) molecule gains traction as a new storage medium with a larger capacity, higher density, and a longer lifespan … >>>
In an ever-growing need for data storage capacity, the Deoxyribonucleic Acid (DNA) molecule gains traction as a new storage medium with a larger capacity, higher density, and a longer lifespan over conventional storage media. To effectively use DNA for data storage, it is important to understand the different methods of encoding information in DNA and compare their effectiveness. This requires evaluating which decoded DNA sequences carry the most encoded information based on various attributes. However, navigating the field of coding theory requires years of experience and domain expertise. For instance, domain experts rely on various mathematical functions and attributes to score and evaluate their encodings. To enable such analytical tasks, we provide an interactive and visual analytical framework for multi-attribute ranking in DNA storage systems. Our framework follows a three-step view with user-settable parameters. It enables users to find the optimal en-/de-coding approaches by setting different weights and combining multiple attributes. We assess the validity of our work through a task-specific user study on domain experts by relying on three tasks. Results indicate that all participants completed their tasks successfully under two minutes, then rated the framework for design choices, perceived usefulness, and intuitiveness. In addition, two real-world use cases are shared and analyzed as direct applications of the proposed tool. DNAsmart enables the ranking of decoded sequences based on multiple attributes. In sum, this work unveils the evaluation of en-/de-coding approaches accessible and tractable through visualization and interactivity to solve comparison and ranking tasks. <<<
翻译
598.
小擎子 (2023-02-28 23:59):
#paper  The cancer chemotherapeutic 5-fluorouracil is a potent Fusobacterium nucleatum inhibitor and its activity is modified by intratumoral microbiota. Cell Rep. 2022 Nov 15;41(7):111625. doi: 10.1016/j.celrep.2022.111625. PMID: 36384132.文章发现结直肠癌里的肿瘤微生物群可以对一线CRC化疗药物5-氟尿嘧啶进行修饰,降低药物的功效。5-氟尿嘧啶既是对结直肠癌上皮细胞有毒性的,也是靶向结肠癌中的核梭杆菌Fn(与癌症进展和复发正相关)的。而肿瘤微生物群修饰5-氟尿嘧啶后,可以减轻对Fn和CRC上皮细胞的毒性。其中结直肠癌肿瘤微生物群里的大肠杆菌在修饰5-氟尿嘧啶的作用得到了证实。文章也用了随机森林对宏基因组数据进行了特征分类,大肠杆菌是5-FU暴露后“修饰者”组的分类,总体而言,具有最高的平均下降精度值,支持大肠杆菌作为模型中分类器的重要性。
IF:7.500Q1 Cell reports, 2022-11-15. DOI: 10.1016/j.celrep.2022.111625 PMID: 36384132
Abstract:
Fusobacterium nucleatum (Fn) is a dominant bacterial species in colorectal cancer (CRC) tissue that is associated with cancer progression and poorer patient prognosis. Following a small-molecule inhibitor screen of 1,846 … >>>
Fusobacterium nucleatum (Fn) is a dominant bacterial species in colorectal cancer (CRC) tissue that is associated with cancer progression and poorer patient prognosis. Following a small-molecule inhibitor screen of 1,846 bioactive compounds against a Fn CRC isolate, we find that 15% of inhibitors are antineoplastic agents including fluoropyrimidines. Validation of these findings reveals that 5-fluorouracil (5-FU), a first-line CRC chemotherapeutic, is a potent inhibitor of Fn CRC isolates. We also identify members of the intratumoral microbiota, including Escherichia coli, that are resistant to 5-FU. Further, CRC E. coli isolates can modify 5-FU and relieve 5-FU toxicity toward otherwise-sensitive Fn and human CRC epithelial cells. Lastly, we demonstrate that ex vivo patient CRC tumor microbiota undergo community disruption after 5-FU exposure and have the potential to deplete 5-FU levels, reducing local drug efficacy. Together, these observations argue for further investigation into the role of the CRC intratumoral microbiota in patient response to chemotherapy. <<<
翻译
599.
cellsarts (2023-02-28 23:46):
#与海底硫循环有关的新酸杆菌类群Novel taxa of Acidobacteriota implicated in seafloor sulfur cycling The ISME Journal (2021) 15:3159–3180 https://doi.org/10.1038/s41396-021-00992-0 酸杆菌广泛存在于海洋沉积物中,但其代谢和生态特性尚不清楚。在这里,我们通过宏基因组组装基因组(MAGs)的功能预测,16S rRNA和异源亚硫酸盐还原酶(dsrB)基因和转录物的扩增子测序,以及四硫酸盐修饰的基因表达分析,研究了斯瓦尔巴群岛海洋沉积物中酸杆菌的代谢和分布。在斯瓦尔巴群岛沉积物中,酸杆菌属是仅次于脱硫杆菌属的第二大含有亚硫酸盐还原酶dsrB的门(平均13%),平均占亚硫酸盐还原酶dsrB转录物的4%。对亚硫酸盐还原酶dsrAB数据集的荟萃分析还显示,酸杆菌的亚硫酸盐还原酶dsrAB序列在全球海洋沉积物中非常突出,平均占所有分析序列的15%,并代表了海洋沉积物中大部分以前未分类的亚硫酸盐还原酶dsrAB。我们提出了两个新的酸杆菌属,Candidatus sulomarinibacter(类Thermoanaerobaculia,“细分23”)和Ca. Polarisedimenticola(“细分22”),它们具有独特的遗传特性,可以解释它们在生物地球化学特征不同的沉积物中的分布。Ca. sulomarinibacter编码灵活的呼吸途径,具有潜在的氧、氧化亚氮、金属氧化物、四硫酸盐、硫和亚硫酸盐/硫酸盐呼吸,并可能发生硫歧化。潜在的营养物质和能量包括纤维素、蛋白质、蓝藻素、氢和醋酸酯。A Ca. Polarisedimenticola MAG编码各种酶来降解蛋白质,并减少氧气,硝酸盐,硫/多硫化物和金属氧化物。Svalbard沉积物的16S rRNA基因和转录谱分析显示,Ca. sulomarinibacter成员在硫化物峡湾沉积物中相对丰富且具有转录活性,而Ca. Polarisedimenticola成员在富金属峡湾沉积物中相对丰富。总的来说,我们揭示了未经培养的海洋酸杆菌的各种生理特征,以及在海底生物地球化学循环中的基本作用。
Abstract:
Acidobacteriota are widespread and often abundant in marine sediments, yet their metabolic and ecological properties are poorly understood. Here, we examined metabolisms and distributions of Acidobacteriota in marine sediments of … >>>
Acidobacteriota are widespread and often abundant in marine sediments, yet their metabolic and ecological properties are poorly understood. Here, we examined metabolisms and distributions of Acidobacteriota in marine sediments of Svalbard by functional predictions from metagenome-assembled genomes (MAGs), amplicon sequencing of 16S rRNA and dissimilatory sulfite reductase (dsrB) genes and transcripts, and gene expression analyses of tetrathionate-amended microcosms. Acidobacteriota were the second most abundant dsrB-harboring (averaging 13%) phylum after Desulfobacterota in Svalbard sediments, and represented 4% of dsrB transcripts on average. Meta-analysis of dsrAB datasets also showed Acidobacteriota dsrAB sequences are prominent in marine sediments worldwide, averaging 15% of all sequences analysed, and represent most of the previously unclassified dsrAB in marine sediments. We propose two new Acidobacteriota genera, Candidatus Sulfomarinibacter (class Thermoanaerobaculia, "subdivision 23") and Ca. Polarisedimenticola ("subdivision 22"), with distinct genetic properties that may explain their distributions in biogeochemically distinct sediments. Ca. Sulfomarinibacter encode flexible respiratory routes, with potential for oxygen, nitrous oxide, metal-oxide, tetrathionate, sulfur and sulfite/sulfate respiration, and possibly sulfur disproportionation. Potential nutrients and energy include cellulose, proteins, cyanophycin, hydrogen, and acetate. A Ca. Polarisedimenticola MAG encodes various enzymes to degrade proteins, and to reduce oxygen, nitrate, sulfur/polysulfide and metal-oxides. 16S rRNA gene and transcript profiling of Svalbard sediments showed Ca. Sulfomarinibacter members were relatively abundant and transcriptionally active in sulfidic fjord sediments, while Ca. Polarisedimenticola members were more relatively abundant in metal-rich fjord sediments. Overall, we reveal various physiological features of uncultured marine Acidobacteriota that indicate fundamental roles in seafloor biogeochemical cycling. <<<
翻译
600.
大勇 (2023-02-28 23:35):
#paper  CD8+ T cells and fatty acids orchestrate tumor ferroptosis and immunity via ACSL4. Cancer Cell. 2022 Apr 11;40(4):365-378.e6. doi: 10.1016/j.ccell.2022.02.003. Epub 2022 Feb 24. 这篇文献主要讲述了CD8+T细胞通过分泌内源性的IFNγ,可以作用与肿瘤细胞,引起ACSL4的表达升高,与花生四烯酸协同促进肿瘤的脂质代谢并诱导肿瘤细胞铁死亡,在此过程中,可以促进肿瘤对免疫检查点抑制剂的疗效。
IF:48.800Q1 Cancer cell, 2022-04-11. DOI: 10.1016/j.ccell.2022.02.003 PMID: 35216678
Abstract:
Tumor cell intrinsic ferroptosis-initiating mechanisms are unknown. Here, we discover that T cell-derived interferon (IFN)γ in combination with arachidonic acid (AA) induces immunogenic tumor ferroptosis, serving as a mode of … >>>
Tumor cell intrinsic ferroptosis-initiating mechanisms are unknown. Here, we discover that T cell-derived interferon (IFN)γ in combination with arachidonic acid (AA) induces immunogenic tumor ferroptosis, serving as a mode of action for CD8 T cell (CTL)-mediated tumor killing. Mechanistically, IFNγ stimulates ACSL4 and alters tumor cell lipid pattern, thereby increasing incorporations of AA into C16 and C18 acyl chain-containing phospholipids. Palmitoleic acid and oleic acid, two common C16 and C18 fatty acids in blood, promote ACSL4-dependent tumor ferroptosis induced by IFNγ plus AA. Moreover, tumor ACSL4 deficiency accelerates tumor progression. Low-dose AA enhances tumor ferroptosis and elevates spontaneous and immune checkpoint blockade (ICB)-induced anti-tumor immunity. Clinically, tumor ACSL4 correlates with T cell signatures and improved survival in ICB-treated cancer patients. Thus, IFNγ signaling paired with selective fatty acids is a natural tumor ferroptosis-promoting mechanism and a mode of action of CTLs. Targeting the ACSL4 pathway is a potential anti-cancer approach. <<<
翻译
回到顶部