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461.
徐炳祥 (2023-08-14 21:58):
#paper doi: 10.1016/j.chembiol.2023.07.001 Cell Chemical Biology, 2023, Small molecule targeting of transcription-replication conflict for selective chemotherapy。本文是最近肿瘤治化疗领域内的一项重要新闻,作者在之前研究的基础上设计了一种新的小分子药物AOH1996,该药物通过增强PCNA与RPB1的结合从而将PCNA带离染色质,进而引起伴随转录的DNA复制抑制和不能被修复的DNA双链断裂损伤。通过此机制,AOH1996实现了对癌细胞的特异性杀灭,而对正常细胞几乎无毒性。动物实验和细胞实验均证明单独使用AOH1996或与其他药物联合对大部分实体肿瘤均有或多或少的疗效。本文再一次展现了针对DNA损伤修复机制的抗肿瘤药物设计的潜力。
Abstract:
Targeting transcription replication conflicts, a major source of endogenous DNA double-stranded breaks and genomic instability could have important anticancer therapeutic implications. Proliferating cell nuclear antigen (PCNA) is critical to DNA … >>>
Targeting transcription replication conflicts, a major source of endogenous DNA double-stranded breaks and genomic instability could have important anticancer therapeutic implications. Proliferating cell nuclear antigen (PCNA) is critical to DNA replication and repair processes. Through a rational drug design approach, we identified a small molecule PCNA inhibitor, AOH1996, which selectively kills cancer cells. AOH1996 enhances the interaction between PCNA and the largest subunit of RNA polymerase II, RPB1, and dissociates PCNA from actively transcribed chromatin regions, while inducing DNA double-stranded breaks in a transcription-dependent manner. Attenuation of RPB1 interaction with PCNA, by a point mutation in RPB1's PCNA-binding region, confers resistance to AOH1996. Orally administrable and metabolically stable, AOH1996 suppresses tumor growth as a monotherapy or as a combination treatment but causes no discernable side effects. Inhibitors of transcription replication conflict resolution may provide a new and unique therapeutic avenue for exploiting this cancer-selective vulnerability. <<<
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462.
AI 5.0.3 (2023-08-01 00:05):
#paper https://doi.org/10.1126/scitranslmed.aba2913 Neurodevelopment and risk for ADHD and depression 7 岁时背侧前额叶皮层和内侧前额叶皮层之间的积极功能连通性较弱与11岁时ADHD症状的减少有关,而背侧前额叶皮层和亚属前扣带皮层之间的积极功能连通性较弱与11岁时情绪相关症状的增加有关。7岁时的大脑连通性比11岁时预测的情绪相关困难比基线症状本身更好,这在具有家庭抑郁症风险的独立样本中得到验证。虽然预测模型需要在更大的独立样本中进行测试,但这些结果表明连接模式作为症状轨迹的生物标志物的潜在效用。
Abstract:
Childhood brain connectivity predicts psychiatric difficulties four years later. >>>
Childhood brain connectivity predicts psychiatric difficulties four years later. <<<
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463.
林海onrush (2023-08-01 00:03):
#paper,doi.org/10.1016/j.aim.2023.109194,Equivariant algebraic K-theory, G-theory and derived completions,论文研究的是群作用下的代数K理论的补全问题。主要内容可概括如下: 文章主要研究线性代数群作用在方案上的等ivariant代数K理论和G理论。目标是证明一个类似Atiyah-Segal在拓扑K理论中补全定理的结果。衍生补全的技术对此问题非常关键。Thomason在80年代就预测到需要一种同伦类的补全方法。本文使用第一作者2008年提出的衍生补全方法。Robert Thomason在建立与Atiyah-Segal对应的等变代数K理论的完备性定理时,发现了强限制性条件过于严格。他对等变代数G理论的情况提出了一个猜想,即对于线性代数群在概型上的作用,存在一个类似Atiyah和Segal的完备性定理,而不需要他之前证明的强限制性条件,这些条件也出现在原始的Atiyah-Segal定理中。 本文的主要目标是在尽可能广泛的背景下,利用导出完备性技术,对该猜想进行证明,并考虑几个应用。解决方案足够广泛,允许所有线性代数群的作用,无论它们是否连通,并作用于任何有限型域上的准投影概型,无论它们是否正则或投影。因此,可以考虑大类的变体的等变代数G理论,例如所有的齐次概型(由一个齐次环作用的情况)和所有球状概型(由一个约化群作用的情况)。通过限制为分裂齐次概型的作用,还可以考虑对代数空间的作用。此外,通常也不需要将基概型限制为域,但主要是为了简化部分阐述。这使得可以得到广泛的应用,其中一些被简要概述,并计划在将来详细探讨。实际上,我们在续篇中讨论了将结果扩展到等变同伦K理论以及各种Riemann-Roch定理。 通过将结果与先前已知的没有使用导出完备性的结果进行比较,可以看出如果不使用导出完备性,只能得到非常限制性的结果。
Abstract:
In the mid 1980s, while working on establishing completion theorems for equivariant Algebraic K-Theory similar to the well-known Atiyah-Segal completion theorem for equivariant topological K-theory, the late Robert Thomason found … >>>
In the mid 1980s, while working on establishing completion theorems for equivariant Algebraic K-Theory similar to the well-known Atiyah-Segal completion theorem for equivariant topological K-theory, the late Robert Thomason found the strong finiteness conditions that are required in such theorems to be too restrictive. Then he made a conjecture on the existence of a completion theorem in the sense of Atiyah and Segal for equivariant algebraic G-theory, for actions of linear algebraic groups on schemes that holds without any of the strong finiteness conditions that are required in such theorems proven by him, and also appearing in the original Atiyah-Segal theorem. The main goal of the present paper is to provide a proof of this conjecture in as broad a context as possible, making use of the technique of derived completion, and to consider several of the applications. Our solution is broad enough to allow actions by all linear algebraic groups, irrespective of whether they are connected or not, and acting on any quasi-projective scheme of finite type over a field, irrespective of whether they are regular or projective. This allows us therefore to consider the equivariant algebraic G-Theory of large classes of varieties like all toric varieties (for the action of a torus) and all spherical varieties (for the action of a reductive group). Restricting to actions by split tori, we are also able to consider actions on algebraic spaces. Moreover, the restriction that the base scheme be a field is also not required often, but is put in mainly to simplify some of our exposition. These enable us to obtain a wide range of applications, some of which are briefly sketched and which we plan to explore in detail in the future. In fact, we discuss an extension of our results to equivariant homotopy K-theory along with various Riemann-Roch theorems in a sequel. A comparison of our results with previously known results, none of which made use of derived completions, shows that without the use of derived completions one can only obtain results which are indeed very restrictive. <<<
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464.
小W (2023-07-31 23:45):
#paper doi:https://doi.org/10.1038/s41591-023-02429-x A multi-ancestry polygenic risk score improves risk prediction for coronary artery disease 本文使用不同祖先来源人群队列的 冠状动脉疾病(CAD) GWASs分析结果,开发了 CAD 多基因风险评分模型(gps) GPSMult ,用于识别 CAD 风险。其模型分为两层:1.使用LDpred2方法为每个群体分层CAD GWAS构建单独的gps, ,综合 不同群体间gps 构建多祖先来源模型;2.采用步进法选择多祖先gps + 临床性状 的最佳组合,构建逻辑回归模型 GPSMult 。本文验证了GPSMult模型 相对于已发布的CAD风险模型在年轻人群或非欧洲人群风险预测性能的提升,倡导GPSMult辅助指导处于边缘或中度CAD风险个体的他汀类药物治疗决策。
IF:58.700Q1 Nature medicine, 2023-07. DOI: 10.1038/s41591-023-02429-x PMID: 37414900
Abstract:
Identification of individuals at highest risk of coronary artery disease (CAD)-ideally before onset-remains an important public health need. Prior studies have developed genome-wide polygenic scores to enable risk stratification, reflecting … >>>
Identification of individuals at highest risk of coronary artery disease (CAD)-ideally before onset-remains an important public health need. Prior studies have developed genome-wide polygenic scores to enable risk stratification, reflecting the substantial inherited component to CAD risk. Here we develop a new and significantly improved polygenic score for CAD, termed GPS, that incorporates genome-wide association data across five ancestries for CAD (>269,000 cases and >1,178,000 controls) and ten CAD risk factors. GPS strongly associated with prevalent CAD (odds ratio per standard deviation 2.14, 95% confidence interval 2.10-2.19, P < 0.001) in UK Biobank participants of European ancestry, identifying 20.0% of the population with 3-fold increased risk and conversely 13.9% with 3-fold decreased risk as compared with those in the middle quintile. GPS was also associated with incident CAD events (hazard ratio per standard deviation 1.73, 95% confidence interval 1.70-1.76, P < 0.001), identifying 3% of healthy individuals with risk of future CAD events equivalent to those with existing disease and significantly improving risk discrimination and reclassification. Across multiethnic, external validation datasets inclusive of 33,096, 124,467, 16,433 and 16,874 participants of African, European, Hispanic and South Asian ancestry, respectively, GPS demonstrated increased strength of associations across all ancestries and outperformed all available previously published CAD polygenic scores. These data contribute a new GPS for CAD to the field and provide a generalizable framework for how large-scale integration of genetic association data for CAD and related traits from diverse populations can meaningfully improve polygenic risk prediction. <<<
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465.
(2023-07-31 23:42):
#paper Analysis of deep sequencing exosome‐microRNA expression profile derivedfrom CP‐II reveals potential role of gga‐miRNA‐451 in inflammation[J].Journal of Cellular and Molecular Medicine, 2020, 24(11):6178-6190.DOI:10.1111/jcmm.15244. 鸡败菌支原体(Mycoplasma gallsepticum, MG)感染会引起鸡呼吸道症状,并可能会导致胚胎死亡率增加,产蛋量减少等。现虽然已有研究报道miRNA在MG感染期间的炎症功能,但外泌体miRNA调节MG诱导炎症的机制仍有待阐明。该研究筛选了MG感染鸡Ⅱ型肺泡细胞外泌体gga-miRNA-451的表达,并预测差异表达miRNA的靶基因和功能。结果表明gga-miR-451可能在感染期间的免疫调节中发挥关键作用,其靶向YWHAZ调节MG诱导的炎症细胞因子的产生。
Abstract:
Mycoplasma gallisepticum (MG) can cause chronic respiratory disease (CRD) in chickens. While several studies have reported the inflammatory functions of microRNAs during MG infection, the mechanism by which exosomal miRNAs … >>>
Mycoplasma gallisepticum (MG) can cause chronic respiratory disease (CRD) in chickens. While several studies have reported the inflammatory functions of microRNAs during MG infection, the mechanism by which exosomal miRNAs regulate MG-induced inflammation remains to be elucidated. The expression of exosome-microRNA derived from MG-infected chicken type II pneumocytes (CP-II) was screened, and the target genes and function of differentially expressed miRNAs (DEGs) were predicted. To verify the role of exosomal gga-miR-451, Western blot, ELISA and RT-qPCR were used in this study. The results showed that a total of 722 miRNAs were identified from the two exosomal small RNA (sRNA) libraries, and 30 miRNAs (9 up-regulated and 21 down-regulated) were significantly differentially expressed. The target miRNAs were significantly enriched in the treatment group, such as cell cycle, Toll-like receptor signalling pathway and MAPK signalling pathway. The results have also confirmed that gga-miR-451-absent exosomes derived from MG-infected CP-II cells increased inflammatory cytokine production in chicken fibroblast cells (DF-1), and wild-type CP-II cell-derived exosomes displayed protective effects. Collectively, our work suggests that exosomes from MG-infected CP-II cells alter the dynamics of the DF-1 cells, and may contribute to pathology of the MG infection via exosomal gga-miR-451 targeting YWHAZ involving in inflammation. <<<
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466.
笑对人生 (2023-07-31 23:37):
#paper doi: 10.1158/1078-0432.CCR-22-2032. Landen CN, et al. Influence of Genomic Landscape on Cancer Immunotherapy for Newly Diagnosed Ovarian Cancer: Biomarker Analyses from the IMagyn050 Randomized Clinical Trial. Clin Cancer Res. 2023 May 1;29(9):1698-1707. doi: 10.1158/1078-0432.CCR-22-2032. 研究背景:2020年7月13日,罗氏宣布阿替利珠单抗(atezolizumab,PD-L1抑制剂)联合贝伐单抗(Avastin,抗血管生成靶向药)、紫杉醇和卡铂一线治疗晚期卵巢癌患者的III期IMagyn050研究未能达到主要终点,相比对照组没有明显改善患者的无进展生存期(PFS)。 研究目的:以IMagyn050 III期临床试验为研究队列,探究携带BRCA1/2突变或同源重组缺陷(Homologous recombination deficient,HRD)的卵巢癌患者能否从atezolizumab中获益。 研究意义:同源重组缺陷(HRD)是HGSOC患者使用聚(ADP- 核糖)聚合酶抑制剂(PARPi)的重要生物标志物。本研究作为一个双盲随机对照临床试验,首次揭示了卵巢癌中BRCA1/2突变或HRD引起的基因不稳定,与免疫检查点治疗敏感性的增强无关。 研究方法:FoundationOne 伴随诊断324基因NGS试剂盒,检测的基因组特征包括BRCA1/2突变、基因组杂合性缺失(genomic, loss of heterozygosity)、TMB和MSI。以PFS作为临床终点,探究其与上述基因组特征的关联。BRCA1/2基因未发生突变,且gLOH发生比例大于等于16%。 研究结果:(1)该队列携带BRCA1/2突变有22%(234/1050)、定位为HRD人群占46%(446/980)。(2)大部分的晚期卵巢癌患者TMB较低,仅有3%患者TMB大于等于10 mut/Mb(29/1024),MSI-high患者也仅有0.3%(3/1022)。(3)携带BRCA2突变的患者PFS优于野生型患者,HRD患者PFS长于修复机制完整患者。(4)与对照组相比,BRCA2突变或HRD组患者无法从atezolizumab中获益。卵巢癌是美国女性因癌症死亡的第五大原因,最常见卵巢癌是高级别浆液性卵巢癌(High-grade serous ovarian cancer, HGSOC)。这类卵巢癌被发现时往往是晚期。目前免疫治疗,尤其免疫检查点抑制剂单药治疗对卵巢癌疗效不佳,未来急需发现更多免疫疗效预测标志物,用于筛选潜在获益人群。
Abstract:
PURPOSE: To explore whether patients with BRCA1/2-mutated or homologous recombination deficient (HRD) ovarian cancers benefitted from atezolizumab in the phase III IMagyn050 (NCT03038100) trial.PATIENTS AND METHODS: Patients with newly diagnosed … >>>
PURPOSE: To explore whether patients with BRCA1/2-mutated or homologous recombination deficient (HRD) ovarian cancers benefitted from atezolizumab in the phase III IMagyn050 (NCT03038100) trial.PATIENTS AND METHODS: Patients with newly diagnosed ovarian cancer were randomized to either atezolizumab or placebo with standard chemotherapy and bevacizumab. Programmed death-ligand 1 (PD-L1) status of tumor-infiltrating immune cells (IC) was determined centrally (VENTANA SP142 assay). Genomic alterations, including deleterious BRCA1/2 alterations, genomic loss of heterozygosity (gLOH), tumor mutation burden (TMB), and microsatellite instability (MSI), were evaluated using the FoundationOne assay. HRD was defined as gLOH ≥ 16%, regardless of BRCA1/2 mutation status. Potential associations between progression-free survival (PFS) and genomic biomarkers were evaluated using standard correlation analyses and log-rank of Kaplan-Meier estimates.RESULTS: Among biomarker-evaluable samples, 22% (234/1,050) harbored BRCA1/2 mutations and 46% (446/980) were HRD. Median TMB was low irrespective of BRCA1/2 or HRD. Only 3% (29/1,024) had TMB ≥10 mut/Mb, and 0.3% (3/1,022) were MSI-high. PFS was better in BRCA2-mutated versus BRCA2-non-mutated tumors and in HRD versus proficient tumors. PD-L1 positivity (≥1% expression on ICs) was associated with HRD but not BRCA1/2 mutations. PFS was not improved by adding atezolizumab in BRCA2-mutated or HRD tumors; there was a trend toward enhanced PFS with atezolizumab in BRCA1-mutated tumors.CONCLUSIONS: Most ovarian tumors have low TMB despite BRCA1/2 mutations or HRD. Neither BRCA1/2 mutation nor HRD predicted enhanced benefit from atezolizumab. This is the first randomized double-blind trial in ovarian cancer demonstrating that genomic instability triggered by BRCA1/2 mutation or HRD is not associated with improved sensitivity to immune checkpoint inhibitors. See related commentary by Al-Rawi et al., p. 1645. <<<
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467.
小擎子 (2023-07-31 23:35):
#paper doi:10.1038/s41467-023-38347-2 Nat Commun, 2023, A general model to predict small molecule substrates of enzymes based on machine and deep learning, 基于机器学习和深度学习的酶小分子底物预测通用模型。可以预测任意1种酶和大约1400种小分子是否为其底物的通用模型。帮助减少确定特定酶的底物分子的筛选范围,帮助降低实验成本。缺点是目前有5%的假阳性率,因此比较适合预测单一酶的候选底物,不适合预测基因组规模代谢模型中的所有酶的候选底物。
IF:14.700Q1 Nature communications, 2023-05-15. DOI: 10.1038/s41467-023-38347-2 PMID: 37188731
Abstract:
For most proteins annotated as enzymes, it is unknown which primary and/or secondary reactions they catalyze. Experimental characterizations of potential substrates are time-consuming and costly. Machine learning predictions could provide … >>>
For most proteins annotated as enzymes, it is unknown which primary and/or secondary reactions they catalyze. Experimental characterizations of potential substrates are time-consuming and costly. Machine learning predictions could provide an efficient alternative, but are hampered by a lack of information regarding enzyme non-substrates, as available training data comprises mainly positive examples. Here, we present ESP, a general machine-learning model for the prediction of enzyme-substrate pairs with an accuracy of over 91% on independent and diverse test data. ESP can be applied successfully across widely different enzymes and a broad range of metabolites included in the training data, outperforming models designed for individual, well-studied enzyme families. ESP represents enzymes through a modified transformer model, and is trained on data augmented with randomly sampled small molecules assigned as non-substrates. By facilitating easy in silico testing of potential substrates, the ESP web server may support both basic and applied science. <<<
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468.
大勇 (2023-07-31 23:24):
#paper Bergholz, J.S., Wang, Q., Wang, Q. et al. PI3Kβ controls immune evasion in PTEN-deficient breast tumours. Nature 617, 139-146 (2023). https://doi.org/10.1038/s41586-023-05940-w 这篇文献在机制方面并没有深入研究,但却是有很好的临床转化前景,在PTEN缺失的肿瘤中,PI3K发挥着重要作用,作者发现其中PI3Kβ是引起该类肿瘤免疫抑制的关键分子,靶向PI3Kβ-BMX-STAT3信号通路可以有效逆转免疫抑制的状态,而且可以促进免疫治疗的疗效
IF:50.500Q1 Nature, 2023-05. DOI: 10.1038/s41586-023-05940-w PMID: 37076617
Abstract:
Loss of the PTEN tumour suppressor is one of the most common oncogenic drivers across all cancer types. PTEN is the major negative regulator of PI3K signalling. The PI3Kβ isoform … >>>
Loss of the PTEN tumour suppressor is one of the most common oncogenic drivers across all cancer types. PTEN is the major negative regulator of PI3K signalling. The PI3Kβ isoform has been shown to play an important role in PTEN-deficient tumours, but the mechanisms underlying the importance of PI3Kβ activity remain elusive. Here, using a syngeneic genetically engineered mouse model of invasive breast cancer driven by ablation of both Pten and Trp53 (which encodes p53), we show that genetic inactivation of PI3Kβ led to a robust anti-tumour immune response that abrogated tumour growth in syngeneic immunocompetent mice, but not in immunodeficient mice. Mechanistically, PI3Kβ inactivation in the PTEN-null setting led to reduced STAT3 signalling and increased the expression of immune stimulatory molecules, thereby promoting anti-tumour immune responses. Pharmacological PI3Kβ inhibition also elicited anti-tumour immunity and synergized with immunotherapy to inhibit tumour growth. Mice with complete responses to the combined treatment displayed immune memory and rejected tumours upon re-challenge. Our findings demonstrate a molecular mechanism linking PTEN loss and STAT3 activation in cancer and suggest that PI3Kβ controls immune escape in PTEN-null tumours, providing a rationale for combining PI3Kβ inhibitors with immunotherapy for the treatment of PTEN-deficient breast cancer. <<<
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469.
张贝 (2023-07-31 23:10):
#paper Structural basis for DNMT3A-mediated de novo DNA methylation. Nature. 2018 Feb 15;554(7692):387-391.doi: 10.1038/nature25477. DNA甲基化会改变基因表达,调节基因组稳定性和细胞分化。在人体中,甲基化过程的失调与各种疾病,特别是癌症有关。DNMT3A和DNMT3B催化哺乳动物的从头甲基化过程,然而,DNMT3底物识别和酶特异性的机制仍不明确。本文报道了分辨率为2.6埃的DNMT3A-DNMT3L-DNA复合物晶体结构,其中两个DNMT3A单体同时攻击两个CpG二核苷酸,两个CpG位点间距离14个碱基对。DNMT3A- DNA相互作用包括一个靶向识别结构域、一个催化loop和DNMT3A同源二聚体interface。靶向识别结构域的Arg836与CpG进行关键作用,确保DNMT3A酶对CpG位点的偏好性。
IF:50.500Q1 Nature, 2018-02-15. DOI: 10.1038/nature25477 PMID: 29414941
Abstract:
DNA methylation by de novo DNA methyltransferases 3A (DNMT3A) and 3B (DNMT3B) at cytosines is essential for genome regulation and development. Dysregulation of this process is implicated in various diseases, … >>>
DNA methylation by de novo DNA methyltransferases 3A (DNMT3A) and 3B (DNMT3B) at cytosines is essential for genome regulation and development. Dysregulation of this process is implicated in various diseases, notably cancer. However, the mechanisms underlying DNMT3 substrate recognition and enzymatic specificity remain elusive. Here we report a 2.65-ångström crystal structure of the DNMT3A-DNMT3L-DNA complex in which two DNMT3A monomers simultaneously attack two cytosine-phosphate-guanine (CpG) dinucleotides, with the target sites separated by 14 base pairs within the same DNA duplex. The DNMT3A-DNA interaction involves a target recognition domain, a catalytic loop, and DNMT3A homodimeric interface. Arg836 of the target recognition domain makes crucial contacts with CpG, ensuring DNMT3A enzymatic preference towards CpG sites in cells. Haematological cancer-associated somatic mutations of the substrate-binding residues decrease DNMT3A activity, induce CpG hypomethylation, and promote transformation of haematopoietic cells. Together, our study reveals the mechanistic basis for DNMT3A-mediated DNA methylation and establishes its aetiological link to human disease. <<<
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470.
白鸟 (2023-07-31 22:58):
#paper https://doi.org/10.1038/s41586-023-06252-9 A spatially resolved single-cell genomic atlas of the adult human breast 该项目是陈-扎克伯格倡议(Chan Zuckerberg Initiative)支持的全球人类细胞图谱(Human Cell Atlas)联盟的一部分,该联盟利用最新技术为人体的每个器官系统构建细胞参考图谱。 研究目的: 人类乳腺的解剖学和组织病理学已经研究了几十年,为发育、哺乳和疾病提供了深入见解。最近,用分子和基因组技术对正常乳腺组织进行了表征,这些方法主要集中在上皮细胞上。迄今为止,仍然缺乏对所有细胞类型及其生物亚型(细胞状态)的无偏的全面解析。 研究意义: 1.HBCA图谱数据为研究乳腺生物学和乳腺癌等疾病状态提供了前所未有的成人正常乳腺组织的参考; 2.HBCA项目的所有单细胞和空间数据都可以通过官方的门户网站公开访问; 3. 人类细胞图谱(HCA,Human Cell Atlas)的一部分;
IF:50.500Q1 Nature, 2023-Aug. DOI: 10.1038/s41586-023-06252-9 PMID: 37380767
Abstract:
The adult human breast is comprised of an intricate network of epithelial ducts and lobules that are embedded in connective and adipose tissue. Although most previous studies have focused on … >>>
The adult human breast is comprised of an intricate network of epithelial ducts and lobules that are embedded in connective and adipose tissue. Although most previous studies have focused on the breast epithelial system, many of the non-epithelial cell types remain understudied. Here we constructed the comprehensive Human Breast Cell Atlas (HBCA) at single-cell and spatial resolution. Our single-cell transcriptomics study profiled 714,331 cells from 126 women, and 117,346 nuclei from 20 women, identifying 12 major cell types and 58 biological cell states. These data reveal abundant perivascular, endothelial and immune cell populations, and highly diverse luminal epithelial cell states. Spatial mapping using four different technologies revealed an unexpectedly rich ecosystem of tissue-resident immune cells, as well as distinct molecular differences between ductal and lobular regions. Collectively, these data provide a reference of the adult normal breast tissue for studying mammary biology and diseases such as breast cancer. <<<
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尹志 (2023-07-31 22:52):
#paper doi: https://doi.org/10.48550/arXiv.2210.13695 Structure-based Drug Design with Equivariant Diffusion Models 又读了一遍这篇文献,用等变扩散模型进行结构化药物设计确实是一种有效的药物设计方式,越来越多的工作也在不断证明它的价值。这篇工作挺经典的(虽然貌似被iclr拒了),它基于蛋白质口袋利用se3等变扩散模型进行了分子生成。大量实验证明它生成药物分子的新颖性和多样性在效率和有效性上都很不错。文章还讨论了使用该方法对现有分子的优化,基于补全进行分子设计等问题,虽然在效果上还存在很多缺陷,但这些思路对于小分子药物设计及现有方法的改进都非常有价值。
Abstract:
Structure-based drug design (SBDD) aims to design small-molecule ligands that bind with high affinity and specificity to pre-determined protein targets. In this paper, we formulate SBDD as a 3D-conditional generation … >>>
Structure-based drug design (SBDD) aims to design small-molecule ligands that bind with high affinity and specificity to pre-determined protein targets. In this paper, we formulate SBDD as a 3D-conditional generation problem and present DiffSBDD, an SE(3)-equivariant 3D-conditional diffusion model that generates novel ligands conditioned on protein pockets. Comprehensive in silico experiments demonstrate the efficiency and effectiveness of DiffSBDD in generating novel and diverse drug-like ligands with competitive docking scores. We further explore the flexibility of the diffusion framework for a broader range of tasks in drug design campaigns, such as off-the-shelf property optimization and partial molecular design with inpainting. <<<
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muton (2023-07-31 22:52):
#paper:https://doi.org/10.1016/j.cub.2021.09.044 The memory trace of a stressful episode压力通过去甲肾上腺素和糖皮质激素对杏仁核和海马体的影响来影响情景记忆的形成。以往研究发现,当我们处在压力情境中时会有一种聚焦效应,也就是对情景中心方面的事情会记得更好。但是如何来用神经证据证明这一观点还未可知。本文作者使用神经表征相似性分析的方法分析了杏仁核脑区在压力情景下遇到物体的记忆情况。结果发现,出现在中心的物体比起出现在两边的物体神经表征的相似性会更高。并且这种更高的相似性预测了更好的记忆效果。这表明,中心物体被紧密地整合到一个以压力为中心的记忆表征中。本研究运用了一种生活化的实验范式巧妙设计并分析了压力情景下的“记忆痕迹”。
IF:8.100Q1 Current biology : CB, 2021-12-06. DOI: 10.1016/j.cub.2021.09.044 PMID: 34653359
Abstract:
Stress influences episodic memory formation via noradrenaline and glucocorticoid effects on amygdala and hippocampus. A common finding is the improvement of memory for central aspects of a stressful episode. This … >>>
Stress influences episodic memory formation via noradrenaline and glucocorticoid effects on amygdala and hippocampus. A common finding is the improvement of memory for central aspects of a stressful episode. This is putatively related to changes in the neural representations of specific experiences, i.e., their memory traces. Here we show that the memory improvement for objects that were encountered in a stressful episode relates to differences in the neural representations of these objects in the amygdala. Using functional magnetic resonance imaging, we found that stress specifically altered the representations of central objects: compared to control objects, they became more similar to one another and more distinct from objects that were not part of this episode. Furthermore, higher similarity of central objects to the main stressor-the faces of the stress-inducing committee members-predicted better memory. This suggests that the central objects were closely integrated into a stressor-centered memory representation. Our findings provide mechanistic insights into how stress shapes the memory trace and have profound implications for neurocognitive models of stressful and emotional memory. <<<
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473.
Ricardo (2023-07-31 22:16):
#paper doi: https://doi.org/10.48550/arXiv.2112.05149 DiffuseMorph: Unsupervised Deformable Image Registration Using Diffusion Model 形变图像配准是医学成像的基本任务之一。经典的配准算法通常需要较高的计算成本进行迭代优化。尽管基于深度学习的图像配准方法已被用于快速图像配准,但要获得从运动图像到固定图像的真实连续形变且拓扑折叠较少,仍然是一个挑战性的问题。为解决这个问题,本文提出一种新的基于扩散模型的图像配准方法DiffuseMorph。DiffuseMorph不仅可以通过反向扩散生成合成的变形图像,而且可以通过变形场进行图像配准。具体来说,形变场由运动图像和固定图像之间的形变的条件得分函数生成,通过简单缩放得分的潜在特征即可从连续形变中进行配准。在2D人脸和3D医学图像配准任务上的实验结果表明,该方法可以提供灵活的形变和拓扑保持能力。
Abstract:
Deformable image registration is one of the fundamental tasks in medical imaging. Classical registration algorithms usually require a high computational cost for iterative optimizations. Although deep-learning-based methods have been developed … >>>
Deformable image registration is one of the fundamental tasks in medical imaging. Classical registration algorithms usually require a high computational cost for iterative optimizations. Although deep-learning-based methods have been developed for fast image registration, it is still challenging to obtain realistic continuous deformations from a moving image to a fixed image with less topological folding problem. To address this, here we present a novel diffusion-model-based image registration method, called DiffuseMorph. DiffuseMorph not only generates synthetic deformed images through reverse diffusion but also allows image registration by deformation fields. Specifically, the deformation fields are generated by the conditional score function of the deformation between the moving and fixed images, so that the registration can be performed from continuous deformation by simply scaling the latent feature of the score. Experimental results on 2D facial and 3D medical image registration tasks demonstrate that our method provides flexible deformations with topology preservation capability. <<<
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半面阳光 (2023-07-31 22:04):
#paper doi: https://doi.org/10.1016/j.gim.2023.100880, Genetics in Medicine, 2023, Molecular diagnostic yield of genome sequencing versus targeted gene panel testing in racially and ethnically diverse pediatric patients.这篇文章比较了基因组测序(GS)与靶向基因panel测序(TGP)两种方式在儿科先证者查因中的患者获益情况。结果显示与基因Panel检测相比,GS检测可以使得儿科先证者的诊断提升一倍,但这一结果目前并未在所有人群中得到证实。
Abstract:
PURPOSE: Adoption of genome sequencing (GS) as a first-line test requires evaluation of its diagnostic yield. We evaluated the GS and targeted gene panel (TGP) testing in diverse pediatric patients … >>>
PURPOSE: Adoption of genome sequencing (GS) as a first-line test requires evaluation of its diagnostic yield. We evaluated the GS and targeted gene panel (TGP) testing in diverse pediatric patients (probands) with suspected genetic conditions.METHODS: Probands with neurologic, cardiac, or immunologic conditions were offered GS and TGP testing. Diagnostic yield was compared using a fully paired study design.RESULTS: A total of 645 probands (median age 9 years) underwent genetic testing, and 113 (17.5%) received a molecular diagnosis. Among 642 probands with both GS and TGP testing, GS yielded 106 (16.5%) and TGPs yielded 52 (8.1%) diagnoses (P < .001). Yield was greater for GS vs TGPs in Hispanic/Latino(a) (17.2% vs 9.5%, P < .001) and White/European American (19.8% vs 7.9%, P < .001) but not in Black/African American (11.5% vs 7.7%, P = .22) population groups by self-report. A higher rate of inconclusive results was seen in the Black/African American (63.8%) vs White/European American (47.6%; P = .01) population group. Most causal copy number variants (17 of 19) and mosaic variants (6 of 8) were detected only by GS.CONCLUSION: GS may yield up to twice as many diagnoses in pediatric patients compared with TGP testing but not yet across all population groups. <<<
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475.
哪有情可长 (2023-07-31 20:26):
#paper Two complementary genes in a presence-absence variation contribute to _indica_-_japonica_ reproductive isolation in rice,Nature Communications,28 July 2023. doi.org/10.1038/s41467-0. 亚洲的栽培稻包括粳稻和梗稻两个亚种,两个亚种之间在形态、生理以及基因水平上存在显著差异,不同种之间的遗传差异会产生强大的杂种优势,而两个亚种之间的生殖隔离也会导致育性下降,结实率降低。该文章通过对两个亚种品种的PAV找到了一个粳稻杂种不育基因座Se,该基因座包含了两个相邻且具有互补效应的基因ORF3和ORF4. ORF3是编码一个具有毒性作用的孢子体花粉的杀手,而ORF4则以配子体方式保护花粉。而粳稻和籼稻杂交F1种。粳型单倍型的花粉由于缺乏ORF4的保护,会受到籼型ORF3的毒性作用导致花粉败育。另外作者又想追溯下Se位点的进化关系,利用14个稻属847分水稻进行基因座的PAV验证,分析。表明Se基因座的出现与AA基因组稻属物种的进化相关。单倍型分析结果表明,Se基因座共包含37种单倍型。根据ORF3_和ORF4的功能和来源,这37种单倍型又可以被进一步得分为5个大类。其中有功能的ORF3以中等频率(74/236)在籼稻中保持,而大多数(132/148)粳稻都缺失了ORF3和ORF4,表明Se基因座的PAV促进了亚洲栽培稻籼粳亚种之间生殖隔离的形成,同时也支持了籼稻和粳稻是由不同的普通野生稻独立驯化而来的理论。同时这个基因座也是cell A natural gene drive system confers reproductive isolation in rice这篇文章定到的位点。CELL更详细的讲了这个基因的分子机理,主要是OPR3可以跟细胞中线粒体的核心功能蛋白互作,干扰线粒体产生能量后导致花粉败育。而ORF4和ORF3互作,使得ORF3不能与核心蛋白互作,解除破坏作用。且ORF3和ORF4形成的复合体可以通过自噬体细胞器进行讲解,彻底消除ORF3的作用。CELL也分析了该基因座的起源和进化,在祖先中不存在,主要是在亚洲的栽培稻祖先-普通野生稻中分化出ORF3和ORF4的功能。经过驯化后,被籼稻继承。
IF:14.700Q1 Nature communications, 2023-07-28. DOI: 10.1038/s41467-023-40189-x PMID: 37507369
Abstract:
Understanding the evolutionary forces in speciation is a central goal in evolutionary biology. Asian cultivated rice has two subspecies, indica and japonica, but the underlying mechanism of the partial reproductive … >>>
Understanding the evolutionary forces in speciation is a central goal in evolutionary biology. Asian cultivated rice has two subspecies, indica and japonica, but the underlying mechanism of the partial reproductive isolation between them remains obscure. Here we show a presence-absence variation (PAV) at the Se locus functions as an indica-japonica reproductive barrier by causing hybrid sterility (HS) in indica-japonica crosses. The locus comprises two adjacent genes: ORF3 encodes a sporophytic pollen killer, whereas ORF4 protects pollen in a gametophytic manner. In F of indica-japonica crosses, pollen with the japonica haplotype, which lacks the sequence containing the protective ORF4, is aborted due to the pollen-killing effect of ORF3 from indica. Evolutionary analysis suggests ORF3 is a gene associated with the Asian cultivated rice species complex, and the PAV has contributed to the reproductive isolation between the two subspecies of Asian cultivated rice. Our analyses provide perspectives on rice inter-subspecies post-zygotic isolation, and will promote efforts to overcome reproductive barriers in indica-japonica hybrid rice breeding. <<<
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476.
Spring (2023-07-31 19:40):
#paper doi: 10.1016/j.chom.2023.06.009 Circulating T cell profiles associate with enterotype signatures underlying hematological malignancy relapses ① 纳入55名接受阿奇霉素(27名)或安慰剂(28名)治疗的患者,收集粪便样本,分析肠道菌群、病毒组和代谢组的时间特征;② 描述四种肠道类型以及相关的细菌噬菌体种群和代谢途径网络;③ 其中一种肠型与持续缓解相关,拟杆菌属的一种分类单元与复发相关,拟杆菌属和普雷沃氏菌属的两种分类单元与完全缓解相关;④ 分类单元与脂质、戊糖和支链氨基酸代谢途径和几种噬菌体种群相关;⑤ 肠型和分类单元与耗竭T细胞和循环免疫细胞的功能状态相关。
IF:20.600Q1 Cell host & microbe, 2023-08-09. DOI: 10.1016/j.chom.2023.06.009 PMID: 37463582
Abstract:
Early administration of azithromycin after allogeneic hematopoietic stem cell transplantation was shown to increase the relapse of hematological malignancies. To determine the impact of azithromycin on the post-transplant gut ecosystem … >>>
Early administration of azithromycin after allogeneic hematopoietic stem cell transplantation was shown to increase the relapse of hematological malignancies. To determine the impact of azithromycin on the post-transplant gut ecosystem and its influence on relapse, we characterized overtime gut bacteriome, virome, and metabolome of 55 patients treated with azithromycin or a placebo. We describe four enterotypes and the network of associated bacteriophage species and metabolic pathways. One enterotype associates with sustained remission. One taxon from Bacteroides specifically associates with relapse, while two from Bacteroides and Prevotella correlate with complete remission. These taxa are associated with lipid, pentose, and branched-chain amino acid metabolic pathways and several bacteriophage species. Enterotypes and taxa associate with exhausted T cells and the functional status of circulating immune cells. These results illustrate how an antibiotic influences a complex network of gut bacteria, viruses, and metabolites and may promote cancer relapse through modifications of immune cells. <<<
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小年 (2023-07-31 19:35):
#paper https://doi.org/10.1038/ncomms13404 Direct identification of clinically relevant neoepitopes presented on native human melanoma tissue by mass spectrometry 这篇研究采用高灵敏度质谱技术,对25名黑色素瘤患者的原发肿瘤组织进行了全面的免疫肽谱学分析,发现了近10万个肿瘤相关肽段。研究团队还首次直接鉴定了携带突变的肽段,其中11个突变肽段在患者样本中得到证实。这些突变肽段中有4个显示出免疫原性,能够诱导患者体内T细胞产生针对癌症的免疫反应。这表明直接通过质谱技术识别突变肽段是寻找个性化肿瘤免疫治疗靶点的有效方法。此外,研究还在未富集的样本中检测到磷酸化肽段,为未来研发癌症免疫治疗提供了潜在目标。虽然该方法灵敏度仍需改进,但研究结果为癌症免疫治疗提供了重要的启示和新方向。
IF:14.700Q1 Nature communications, 2016-11-21. DOI: 10.1038/ncomms13404 PMID: 27869121
Abstract:
Although mutations may represent attractive targets for immunotherapy, direct identification of mutated peptide ligands isolated from human leucocyte antigens (HLA) on the surface of native tumour tissue has so far … >>>
Although mutations may represent attractive targets for immunotherapy, direct identification of mutated peptide ligands isolated from human leucocyte antigens (HLA) on the surface of native tumour tissue has so far not been successful. Using advanced mass spectrometry (MS) analysis, we survey the melanoma-associated immunopeptidome to a depth of 95,500 patient-presented peptides. We thereby discover a large spectrum of attractive target antigen candidates including cancer testis antigens and phosphopeptides. Most importantly, we identify peptide ligands presented on native tumour tissue samples harbouring somatic mutations. Four of eleven mutated ligands prove to be immunogenic by neoantigen-specific T-cell responses. Moreover, tumour-reactive T cells with specificity for selected neoantigens identified by MS are detected in the patient's tumour and peripheral blood. We conclude that direct identification of mutated peptide ligands from primary tumour material by MS is possible and yields true neoepitopes with high relevance for immunotherapeutic strategies in cancer. <<<
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478.
庞庞 (2023-07-31 19:14):
#paper doi:10.1038/s41380-021-01247-2, Disrupted intrinsic functional brain topology in patients with major depressive disorder 之前人们去比较抑郁症和正常人大脑功能的拓扑差异,结果多有不同。这可能是因为数据量不够的原因。严超赣课题组使用了16个站点的821名MDD患者和765名正常对照,发现与正常人相比,抑郁症患者的全局和局部效率降低。在节点水平上,患者感觉运动网络(SMN)、背侧注意网络(DAN)和视觉网络(VN)的节点度降低,默认模式网络(DMN)、SMN、DAN和VN的节点效率降低。
IF:9.600Q1 Molecular psychiatry, 2021-12. DOI: 10.1038/s41380-021-01247-2 PMID: 34385597
Abstract:
Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address this issue, we utilized a … >>>
Aberrant topological organization of whole-brain networks has been inconsistently reported in studies of patients with major depressive disorder (MDD), reflecting limited sample sizes. To address this issue, we utilized a big data sample of MDD patients from the REST-meta-MDD Project, including 821 MDD patients and 765 normal controls (NCs) from 16 sites. Using the Dosenbach 160 node atlas, we examined whole-brain functional networks and extracted topological features (e.g., global and local efficiency, nodal efficiency, and degree) using graph theory-based methods. Linear mixed-effect models were used for group comparisons to control for site variability; robustness of results was confirmed (e.g., multiple topological parameters, different node definitions, and several head motion control strategies were applied). We found decreased global and local efficiency in patients with MDD compared to NCs. At the nodal level, patients with MDD were characterized by decreased nodal degrees in the somatomotor network (SMN), dorsal attention network (DAN) and visual network (VN) and decreased nodal efficiency in the default mode network (DMN), SMN, DAN, and VN. These topological differences were mostly driven by recurrent MDD patients, rather than first-episode drug naive (FEDN) patients with MDD. In this highly powered multisite study, we observed disrupted topological architecture of functional brain networks in MDD, suggesting both locally and globally decreased efficiency in brain networks. <<<
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479.
符毓 (2023-07-31 16:41):
#paper doi: 10.48550/arXiv.2307.05973 2023, Composable 3D Value Maps for Robotic Manipulation with Language Models. 李飞飞团队最新论文研究,把语言模型与机器人操作结合。与大语言模型结合后人机交互效率得到提高,并且能做到基于视觉的实时轨迹规划。目测机械臂移动速率为常见机械臂工作速率的八分之一,到真实应用的话稳定性还需要进一步提高(超过25%的出错率)
Abstract:
Large language models (LLMs) are shown to possess a wealth of actionable knowledge that can be extracted for robot manipulation in the form of reasoning and planning. Despite the progress, … >>>
Large language models (LLMs) are shown to possess a wealth of actionable knowledge that can be extracted for robot manipulation in the form of reasoning and planning. Despite the progress, most still rely on pre-defined motion primitives to carry out the physical interactions with the environment, which remains a major bottleneck. In this work, we aim to synthesize robot trajectories, i.e., a dense sequence of 6-DoF end-effector waypoints, for a large variety of manipulation tasks given an open-set of instructions and an open-set of objects. We achieve this by first observing that LLMs excel at inferring affordances and constraints given a free-form language instruction. More importantly, by leveraging their code-writing capabilities, they can interact with a visual-language model (VLM) to compose 3D value maps to ground the knowledge into the observation space of the agent. The composed value maps are then used in a model-based planning framework to zero-shot synthesize closed-loop robot trajectories with robustness to dynamic perturbations. We further demonstrate how the proposed framework can benefit from online experiences by efficiently learning a dynamics model for scenes that involve contact-rich interactions. We present a large-scale study of the proposed method in both simulated and real-robot environments, showcasing the ability to perform a large variety of everyday manipulation tasks specified in free-form natural language. Project website: this https URL <<<
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480.
Vincent (2023-07-31 14:42):
#paper Deep learning-based prediction of the T cell receptor–antigen binding specificity https://doi.org/10.1038/s42256-021-00383-2 2021 nature machine intelligence. 肿瘤新抗原在T细胞识别肿瘤细胞的过程中发挥着重要的作用,肿瘤新抗原与T细胞受体的结合与相互作用预测一直备受关注,然而相关的实验与计算方法一直有诸多不足,可验证性也很差。这篇文章开发了一套基于迁移学习的机器学习方法pMTnet,来预测抗原MHC结合物与T细胞受体的结合能力。通过将pMTnet运用到人的肿瘤基因组数据上,发现肿瘤新抗原比自身抗原的免疫原性更高,拥有对肿瘤新抗原结合能力强的T细胞克隆的病人在免疫治疗中有更好的预后和治疗效果。
Abstract:
Neoantigens play a key role in the recognition of tumor cells by T cells. However, only a small proportion of neoantigens truly elicit T cell responses, and fewer clues exist … >>>
Neoantigens play a key role in the recognition of tumor cells by T cells. However, only a small proportion of neoantigens truly elicit T cell responses, and fewer clues exist as to which neoantigens are recognized by which T cell receptors (TCRs). We built a transfer learning-based model, named pMHC-TCR binding prediction network (pMTnet), to predict TCR-binding specificities of neoantigens, and T cell antigens in general, presented by class I major histocompatibility complexes (pMHCs). pMTnet was comprehensively validated by a series of analyses, and showed advance over previous work by a large margin. By applying pMTnet in human tumor genomics data, we discovered that neoantigens were generally more immunogenic than self-antigens, but HERV-E, a special type of self-antigen that is re-activated in kidney cancer, is more immunogenic than neoantigens. We further discovered that patients with more clonally expanded T cells exhibiting better affinity against truncal, rather than subclonal, neoantigens, had more favorable prognosis and treatment response to immunotherapy, in melanoma and lung cancer but not in kidney cancer. Predicting TCR-neoantigen/antigen pairs is one of the most daunting challenges in modern immunology. However, we achieved an accurate prediction of the pairing only using the TCR sequence (CDR3β), antigen sequence, and class I MHC allele, and our work revealed unique insights into the interactions of TCRs and pMHCs in human tumors using pMTnet as a discovery tool. <<<
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