LSC

LSC
  • 文章类型: Journal Article
    胶体量子点(QDs)由于其出色的光稳定性和通过涉及尺寸的基本原理可调节的特性,因此在太阳能技术中具有广阔的前景,核和壳的原子组成,形状,表面状态。然而,太阳能转换中大多数高性能量子点都含有有害金属元素,包括Cd和Pb,造成重大环境风险。这里,我们对太阳能技术的无重金属胶体量子点进行了全面综述,包括光伏器件,太阳能到化学燃料的转化,和发光太阳能聚光器。我们分析了新兴的合成策略,以通过调整能带结构和操纵QD内和QD/电荷受体界面处的电荷动力学来优化光学特性。我们还对不同的合成方法进行了比较分析,讨论这些材料中的结构-性质关系,并将它们与太阳能设备的性能相关联。最后我们展望了今后工作的挑战和机遇,包括基于机器学习的设计,可持续合成,和新的表面/界面工程。本文受版权保护。保留所有权利。
    Colloidal quantum dots (QDs) hold great promise as building blocks in solar technologies owing to their remarkable photostability and adjustable properties through the rationale involving size, atomic composition of core and shell, shapes, and surface states. However, most high-performing QDs in solar conversion contain hazardous metal elements, including Cd and Pb, posing significant environmental risks. Here, a comprehensive review of heavy-metal-free colloidal QDs for solar technologies, including photovoltaic (PV) devices, solar-to-chemical fuel conversion, and luminescent solar concentrators (LSCs), is presented. Emerging synthetic strategies to optimize the optical properties by tuning the energy band structure and manipulating charge dynamics within the QDs and at the QDs/charge acceptors interfaces, are analyzed. A comparative analysis of different synthetic methods is provided, structure-property relationships in these materials are discussed, and they are correlated with the performance of solar devices. This work is concluded with an outlook on challenges and opportunities for future work, including machine learning-based design, sustainable synthesis, and new surface/interface engineering.
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  • 文章类型: Journal Article
    90Sr和210Pb被认为是饮食摄入导致的内部暴露中的关键放射性核素,然而,用于检测它们的既定方法是耗时的。开发了一种通过LSC测量使用Sr·spec树脂顺序分离90Sr和210Pb的方法,这是非常适合食品安全监测作为其最低的样品要求。样品中Sr和Pb的顺序分离为0.05mol/LHNO3和0.05mol/LC6H5O7(NH4)3。使用ICP-OES测量的Sr和Pb的化学回收率分别为72-83%和80-88%,分别。食品样品中90Sr和210Pb的最低可检测活性分别为36.2mBq/kg和28.6mBq/kg,分别,从0.1kg新鲜样品和300分钟计数时间获得。使用参考材料对该方法进行了验证,并与其他方法进行了比较。开发的方法用于其他高度复杂的食品基质的可行性需要进一步研究。
    90Sr and 210Pb are considered to be key radionuclides in internal exposure resulting from dietary intake, however, the established methods employed for their detection are time-comsuming. A method for the sequential separation of 90Sr and 210Pb using a Sr·spec resin by LSC measurement is developed, which is highly suitable for food safety monitoring as its minimal sample requirements. The sequential separation of Sr and Pb from the sample was using 0.05 mol/L HNO3 and 0.05 mol/L C6H5O7(NH4)3. The chemical recoveries of Sr and Pb measured using ICP-OES were 72-83% and 80-88%, respectively. The minimum detectable activities of 90Sr and 210Pb in the food sample were 36.2 mBq/kg and 28.6 mBq/kg, respectively, obtained from a 0.1 kg fresh sample and 300 min counting time. The method was validated using reference materials and compared with other methods. The feasibility of the developed method for other highly complex food matrices needs further investigation.
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  • 文章类型: Journal Article
    CSF1R是一种受体酪氨酸激酶,负责巨噬细胞的生长/存活/极化,并在一些AML患者中过表达。我们假设一种新型的多激酶抑制剂(TKi),纳拉沙利布(HX301/ON123300),对CSF1R具有高效力(IC50〜0.285nM),会产生抗AML效果。我们通过证实HX301对CSF1R的高效(IC50~0.285nM)进行了测试,以及其他激酶,例如FLT3(IC50为~19.77nM)和CDK6(0.53nM)。体外增殖试验表明,在CSF1R或突变型FLT3-ITD变体可能是增殖驱动因素的细胞培养物中,那拉齐利布具有很高的生长抑制作用,包括原代巨噬细胞(IC50为72.5nM)和AML系的子集(IC50<1.5μM)。使用五种AML异种移植物对那拉齐尼进行体内药理学建模,导致:抑制MV4-11(FLT3-ITD)皮下肿瘤生长和完全抑制AM7577-PDX(FLT3-ITD/CSF1Rmed)全身生长,可能是由于抑制FLT3-ITD活性;完全抑制AM8096-PDX(CSF1Rhi/野生型FLT3)生长,可能是由于CSF1R(“推定驱动因素”)的抑制;AM5512-PDX和AM7407-PDX(野生型FLT3/CSF1Rlo)均无反应。白血病骨髓负荷显著减少,疾病起源的地方,在两个响应者中也实现了(AM7577/AM8096),暗示HX301可能比仅影响外周白血病细胞的治疗更有效。总之,纳拉沙尼布可能是治疗患有CSF1Rhi和/或突变型FLT3-ITD的AML亚群的候选药物,特别是第二代FLT3抑制剂抗性变体。
    CSF1R is a receptor tyrosine kinase responsible for the growth/survival/polarization of macrophages and overexpressed in some AML patients. We hypothesized that a novel multi-kinase inhibitor (TKi), narazaciclib (HX301/ON123300), with high potency against CSF1R (IC50 ~ 0.285 nM), would have anti-AML effects. We tested this by confirming HX301\'s high potency against CSF1R (IC50 ~ 0.285 nM), as well as other kinases, e.g. FLT3 (IC50 of ~ 19.77 nM) and CDK6 (0.53 nM). An in vitro proliferation assay showed that narazaciclib has a high growth inhibitory effect in cell cultures where CSF1R or mutant FLT3-ITD variants that may be proliferation drivers, including primary macrophages (IC50 of 72.5 nM) and a subset of AML lines (IC50 < 1.5 μM). In vivo pharmacology modeling of narazaciclib using five AML xenografts resulted in: inhibition of MV4-11 (FLT3-ITD) subcutaneous tumor growth and complete suppression of AM7577-PDX (FLT3-ITD/CSF1Rmed) systemic growth, likely due to the suppression of FLT3-ITD activity; complete suppression of AM8096-PDX (CSF1Rhi/wild-type FLT3) growth, likely due to the inhibition of CSF1R (\"a putative driver\"); and nonresponse of both AM5512-PDX and AM7407-PDX (wild-type FLT3/CSF1Rlo). Significant leukemia load reductions in bone marrow, where disease originated, were also achieved in both responders (AM7577/AM8096), implicating that HX301 might be a potentially more effective therapy than those only affecting peripheral leukemic cells. Altogether, narazaciclib can potentially be a candidate treatment for a subset of AML with CSF1Rhi and/or mutant FLT3-ITD variants, particularly second generation FLT3 inhibitor resistant variants.
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  • 文章类型: Journal Article
    继发性急性髓性白血病(sAML)是一种异质性恶性造血疾病,由包括骨髓增生异常综合征(MDS)在内的早期血液病(AHD)引起,骨髓增殖性肿瘤(MPN),再生障碍性贫血(AA),或由于暴露于基因毒性化学治疗剂或放射疗法(治疗相关的AML,tAML)。当骨髓或外周血中的母细胞数≥20%时,诊断为sAML,它的特点是预后差,对治疗的抵抗力和较低的总体生存率。随着下一代测序技术的最新进展,我们对与sAML进化相关的分子事件的理解显著增加,并为开发新疗法开辟了新的视角.与sAML相关的遗传畸变会影响参与剪接等过程的基因,染色质修饰和基因组完整性。此外,非编码RNA成为白血病发生的重要促成因素。几十年来,继发性AML的标准治疗是阿糖胞苷和柔红霉素的7+3方案,可以延长几个月的生存期,但是在剂量或递送方面的修改已经大大延长了这段时间。除了传统的化疗,造血干细胞移植,CAR-T细胞疗法和小分子抑制剂也已经出现用于治疗sAML。
    Secondary acute myeloid leukemia (sAML) is a heterogeneous malignant hematopoietic disease that arises either from an antecedent hematologic disorder (AHD) including myelodysplastic syndromes (MDS), myeloproliferative neoplasms (MPN), aplastic anemia (AA), or as a result of exposure to genotoxic chemotherapeutic agents or radiotherapy (therapy related AML, tAML). sAML is diagnosed when the number of blasts is ≥20% in the bone marrow or peripheral blood, and it is characterized by poor prognosis, resistance to therapy and low overall survival rate. With the recent advances in next generation sequencing technologies, our understanding of the molecular events associated with sAML evolution has significantly increased and opened new perspectives for the development of novel therapies. The genetic aberrations that are associated with sAML affect genes involved in processes such as splicing, chromatin modification and genome integrity. Moreover, non-coding RNAs\' emerged as an important contributing factor to leukemogenesis. For decades, the standard treatment for secondary AML has been the 7 + 3 regimen of cytarabine and daunorubicin which prolongs survival for several months, but modifications in either dosage or delivery has significantly extended that time. Apart from traditional chemotherapy, hematopoietic stem cell transplantation, CAR-T cell therapy and small molecule inhibitors have also emerged to treat sAML.
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  • 文章类型: Journal Article
    在决策中,例如,符合规范,如参考值或要求,适用的决策规则应记录在案。此外,如果在决策过程中考虑了测量不确定性,则相关的概率,或风险,应考虑测量结果高于(或低于)参考值。在这项工作中,表明对于总α和总β测量,评估方法,GUMUF(GUM不确定性框架)或MC(蒙特卡洛),当测量结果非常接近参考值时,可能也很重要,并影响做出的决定。因此,输入量的评估方法和假设对于文档也可能很重要。此外,无论决策规则和评估方法的选择如何,测量结果的决策者或使用者都应意识到由于评估方法而可能产生的差异和/或后果。
    In decision making, e.g. conformity to a specification like a reference value or a requirement, the decision rule applied shall be documented. Furthermore, if the measurement uncertainty is considered in the decision process the associated probability, or risk, that a measurement result is above (or below) a reference value shall be taken into account. In this work it is shown that for gross alpha and gross beta measurements the evaluation method, GUMUF (GUM Uncertainty Framework) or MC (Monte Carlo), may also be important and influence the decisions taken when measurement results are very close to the reference value. Therefore the evaluation method and assumptions of the input quantities may also be important to document. Moreover, decision makers or users of measurement results should be aware of possible differences and/or consequences due to the evaluation method regardless of the decision rule and the choice of evaluation method.
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  • 文章类型: Journal Article
    急性髓系白血病(AML)的治疗正在迅速发展,但是对治疗的原发性和获得性耐药性使持久治疗的前景变得复杂。最近的功能和单细胞多组学方法极大地扩展了我们对AML设置中谱系轨迹多样性的认识。AML细胞范围从未分化的干细胞样细胞到更分化的髓样或巨核细胞/红系细胞。目前临床相关药物主要针对骨髓祖细胞谱系,而单核细胞或干细胞样状态可以逃避当前的AML治疗,并且将来可能会靶向谱系特异性抑制剂。AML细胞在治疗压力下异常谱系可塑性的程度以及正常分化途径的劫持仍然是一个知之甚少的话题。对AML干细胞谱系可塑性机制的见解可以识别治疗特异性和交叉耐药途径,并揭示克服它们的新策略。
    Acute myeloid leukemia (AML) therapy is undergoing rapid development, but primary and acquired resistance to therapy complicates the prospect of a durable cure. Recent functional and single-cell multi-omics approaches have greatly expanded our knowledge of the diversity of lineage trajectories in AML settings. AML cells range from undifferentiated stem-like cells to more differentiated myeloid or megakaryocyte/erythroid cells. Current clinically relevant drugs predominantly target the myeloid progenitor lineage, while monocyte- or stem cell-like states can evade current AML treatment and may be targeted in the future with lineage-specific inhibitors. The extent of aberrant lineage plasticity upon therapeutic pressure in AML cells in conjunction with hijacking of normal differentiation pathways is still a poorly understood topic. Insights into the mechanisms of lineage plasticity of AML stem cells could identify both therapy-specific and cross-drug resistance pathways and reveal novel strategies to overcome them.
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  • 文章类型: Journal Article
    镭的228Ra和226Ra同位素是食品中的重要污染物,引起公众的关注,因为它们的放射性毒性。有几种方法可用于测定228Ra和226Ra。然而,这些程序的应用不集中在食物上,而只集中在水和环境基质上。在这项研究中,开发了一种使用液体闪烁计数同时测定食品样品中226Ra和228Ra放射性的经济有效的方法。食品样品中226Ra和228Ra的整体效率分别为69.4-78.4%和30.1-35.8%,分别。226Ra和228Ra的最小可检测活性为11.3mBq/g和33.4mBq/g,分别,在我们的食物样本中,使用1.0g灰分样品和60分钟的计数时间获得。该方法使用IAEA认证的参考材料进行了验证,并与使用伽马光谱法在茶叶中获得的数据进行了比较,海带,和牡蛎样本。
    The 228Ra and 226Ra isotopes of radium are significant contaminants in food, raising public concern because of their radiotoxicity. Several methods are available for determining 228Ra and 226Ra. However, the application of these procedures is not focused on food but only on water and environmental matrices. In this study, a cost-effective method for the simultaneous determination of 226Ra and 228Ra radioactivity in food samples using liquid scintillation counting was developed. The overall efficiencies of 226Ra and 228Ra in the food samples are 69.4-78.4% and 30.1-35.8%, respectively. The minimum detectable activities of 226Ra and 228Ra are 11.3 mBq/g and 33.4 mBq/g, respectively, in our food sample, obtained using a 1.0 g ash sample and 60 min of counting time. The method was validated using IAEA-certified reference materials and compared with data obtained using gamma spectrometry in tea, kelp, and oyster samples.
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  • 文章类型: Journal Article
    在这项研究中,我们报告了一种新的分析方法,该方法利用氧化燃烧分离结合CaCO3悬浮液的沉淀物进行液体闪烁计数(LSC)来测定海洋生物中的14C。对影响管式燃烧炉氧化燃烧效率和LSC计数效率的主要因素进行了系统的研究和优化。在最佳燃烧条件下,五个海洋样品的碳燃烧回收率为85.6%至92.4%。该方法对14C的检出限为0.13Bq/g,重复性为3.9-9.1%。分析周转时间为6h,最多可以同时处理六个样本。对不确定度分量的评估表明,计数中的不确定度是最大的贡献者,其次是燃烧恢复和计数效率。所开发的方法能够可靠地测量海洋生物中的14C,为风险评估提供有价值的分析工具。
    In this study, we report a new analytical method for determination of 14C in marine biota utilizing oxidation combustion separation combined with CaCO3 suspension of precipitates for liquid scintillation counting (LSC). The main factors affecting the oxidation combustion efficiency of tube combustion furnace and the counting efficiency of the LSC were systematically investigated and optimized. Under the optimal combustion conditions, the combustion recovery of carbon ranged from 85.6 % to 92.4 % for five marine samples. And the method achieved a detection limit of 0.13 Bq/g for 14C and repeatability of 3.9-9.1 %. The analytical turnover time was 6 h, and up to six samples could be processed simultaneously. Assessment of uncertainty components showed that the uncertainty in counting was the largest contributor, followed by combustion recovery and counting efficiency. The developed method enables reliable measurement of 14C in marine biota, providing valuable analytical tool for risk assessment purposes.
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  • 文章类型: Journal Article
    这项研究比较了定量石墨样品中36Cl的质量活性的不同方法。所有方法都包括燃烧步骤与捕集溶液相结合以收集挥发性元素。使用两种不同的树脂从基质中分离36Cl(CL树脂和PS树脂)。液体闪烁计数(LSC),使用闪烁计数(SC)和串联电感耦合等离子体质谱(ICP-MS/MS)来定量36Cl活性。所有方法中的化学产率均通过离子色谱法(IC)确定。此外,将这些方法应用于实际的活化石墨样品。
    This study compares different approaches for the quantification of the massic activity of 36Cl in graphite samples. All approaches consisted of a combustion step in combination with a trapping solution to collect the volatile elements. Two different resins were used to separate 36Cl from the matrix (CL resin and PS resin). Liquid scintillation counting (LSC), scintillation counting (SC) and tandem inductively coupled plasma mass spectrometry (ICP-MS/MS) were used to quantify 36Cl activity. The chemical yield in all approaches was determined by means of ion chromatography (IC). In addition, the methods were applied to a real activated graphite sample.
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  • 文章类型: Journal Article
    目的:疾病复发和治疗耐药仍然是癌症治疗的严重障碍。白血病干细胞(LSC)具有治疗抗性和复发的原因。深度静止状态似乎使癌症干细胞(CSC)能够获得对疾病进展和治疗抵抗至关重要的新体细胞突变。正常造血干细胞(HSC)和LSC具有许多共同特征,从而使LSC的安全消除复杂化。最近的一项研究表明,长寿的正常卵母细胞存在没有线粒体复合物I(MC-1),以发育调节的方式表达,从而减轻他们对ROS的脆弱性。静态CSC依靠线粒体FAO,没有复杂的I表达式,从而避免了破坏性ROS的产生,类似于长寿的正常人干细胞。对治疗抗性生物学的更深入了解对于开发最佳策略以实现完全治愈白血病很重要。
    方法:这里,使用scRNA测序和ATAC-seq对原发性慢性粒细胞白血病(CML)患者样本,结合生物信息学分析,我们进一步检查了先前表征的体外伊马替尼选择的CD34-CD38-CMLLSC群体的异质性.我们利用了一系列的功能分析,包括单细胞代谢组学和海马分析,以验证最深的静态白血病引发剂(LI)子集的存在。
    结果:目前的研究揭示了CML患者治疗耐药LSC的异质性及其存在两种功能上不同的状态。最深层静止的LI抑制MC-1的表达,但高度依赖于脂肪酸氧化(FAO)的代谢需求,并且ATAC-seq显示该人群中染色质可及性增加。所有这些都符合极其原始的,静止的干性转录签名。重要的是,特异性CREB结合蛋白(CBP)/β-catenin拮抗剂ICG-001启动LSC的分化,包括LI,随着分化和MC-1,CD34,CD38和BCR-ABL1表达增加,从而降低染色质可及性,从而使它们对伊马替尼重新敏感。
    结论:我们研究了CML患者与LSC异质性相关的生物学方面,并证明了特定小分子CBP/β-catenin拮抗剂安全消除深度静止治疗耐药CSC的能力。这些观察结果可能代表了一种有吸引力的可推广的治疗策略,可以帮助开发更好的方案来根除静止的LSC群体。
    OBJECTIVE: Disease relapse and therapy resistance remain serious impediments to treating cancer. Leukemia stem cells (LSC) are therapy resistant and the cause of relapse. A state of deep quiescence appears to enable cancer stem cells (CSC) to acquire new somatic mutations essential for disease progression and therapy resistance. Both normal hematopoietic stem cells (HSC) and LSC share many common features, thereby complicating the safe elimination of LSC. A recent study demonstrated that long lived normal oocytes exist without mitochondrial complex I (MC-1), expressing it in a developmentally regulated fashion, thereby mitigating their vulnerability to ROS. Quiescent CSC rely on mitochondrial FAO, without complex I expression, thereby avoiding the generation of damaging ROS, similar to long lived normal human stem cells. A deeper understanding of the biology of therapy resistance is important for the development of optimal strategies to attain complete leukemia cures.
    METHODS: Here, using scRNA-sequencing and ATAC-seq on primary chronic myelogenous leukemia (CML) patient samples, combined with bioinformatics analyses, we further examine the heterogeneity of a previously characterized in vitro imatinib-selected CD34-CD38- CML LSC population. We utilized a series of functional analyses, including single-cell metabolomic and Seahorse analyses, to validate the existence of the deepest quiescent leukemia initiators (LI) subset.
    RESULTS: Current study revealed heterogeneity of therapy resistant LSC in CML patients and their existence of two functionally distinct states. The most deeply quiescent LI suppress the expression of MC-1, yet are highly dependent on fatty acid oxidation (FAO) for their metabolic requirements and ATAC-seq demonstrated increased chromatin accessibility in this population, all consistent with an extremely primitive, quiescent stemness transcriptional signature. Importantly, the specific CREB binding protein (CBP)/β-catenin antagonist ICG-001 initiates the differentiation of LSC, including LI, decreases chromatin accessibility with differentiation and increasing expression of MC-1, CD34, CD38 and BCR-ABL1, thereby resensitizing them to imatinib.
    CONCLUSIONS: We investigated the biological aspects related to LSC heterogeneity in CML patients and demonstrated the ability of specific small molecule CBP/β-catenin antagonists to safely eliminate deeply quiescent therapy resistant CSC. These observations may represent an attractive generalizable therapeutic strategy that could help develop better protocols to eradicate the quiescent LSC population.
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