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共载吲哚菁绿和siSphK1的pH/NIR双响应性金属有机框架复合纳米颗粒的制备及体外抗非小细胞肺癌的研究
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作者 吕冰洁 闫晓红 +3 位作者 于飞 胡浩然 王路路 杨阳 《中国病理生理杂志》 北大核心 2025年第8期1550-1558,共9页
目的:构建一种共载吲哚菁绿(indocyanine green,ICG)和鞘氨醇激酶1(sphingosine kinase 1,SphK1)siRNA(siSphK1)的pH/近红外(near-infrared,NIR)双响应性金属有机框架复合纳米颗粒,并评估其在非小细胞肺癌A549细胞中的抗肿瘤作用。方法... 目的:构建一种共载吲哚菁绿(indocyanine green,ICG)和鞘氨醇激酶1(sphingosine kinase 1,SphK1)siRNA(siSphK1)的pH/近红外(near-infrared,NIR)双响应性金属有机框架复合纳米颗粒,并评估其在非小细胞肺癌A549细胞中的抗肿瘤作用。方法:通过合成ZIF-8纳米颗粒,负载ICG和siSphK1,制备ZIF-8@ICG@si‑SphK1纳米颗粒。利用透射电子显微镜、动态光散射技术和X射线衍射表征纳米颗粒的表观形貌、粒径大小、表面电位和晶体结构。考察纳米颗粒的稳定性、对siSphK1的包封和保护作用以及pH/NIR响应性。通过Western blot、RT-qPCR、MTT实验、流式细胞术和活性氧(reactive oxygen species,ROS)荧光染色评估纳米颗粒在A549细胞中的基因沉默效果和抗肿瘤活性。结果:ZIF-8@ICG@siSphK1纳米颗粒呈典型的多面体结构,平均粒径为(76.8±0.9)nm,ζ电位为(9.2±0.1)mV。纳米颗粒可成功包封siSphK1,保护其免受RNase降解,并展现出良好的NIR响应性,光热转换效率达到39.7%。在808 nm激光照射10 h后,siRNA在pH 5.5环境中的累积释放量显著高于在pH 7.4环境中的释放量。在A549细胞中,ZIF-8@ICG@siSphK1纳米颗粒在NIR照射下能够有效递送siSphK1,显著下调SphK1基因表达,显著抑制细胞增殖、诱导细胞凋亡并提高细胞内ROS水平。结论:ZIF-8@ICG@siSphK1纳米颗粒通过基因沉默和光热疗法的联合作用,可有效地增强对A549细胞的杀伤效应。 展开更多
关键词 吲哚菁绿 鞘氨醇激酶1 pH/nir双响应性 非小细胞肺癌
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基于VIS-NIR-SIR谱段信息的茶叶硒元素光谱特征分析
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作者 舒田 郭松 +4 位作者 冯恩英 刘春艳 文竹 彭顺正 杨文 《贵州农业科学》 2025年第5期125-133,共9页
[目的]探究茶叶硒元素的反射光谱特征和敏感波段,为富硒茶硒元素的高光谱遥感快速无损检测提供参考。[方法]以福鼎大白茶叶为研究对象,利用地物光谱仪测定不同硒浓度[0(CK)、2.5mg/L、5.0 mg/L、10.0 mg/L]处理后不同时间节点(第6天、... [目的]探究茶叶硒元素的反射光谱特征和敏感波段,为富硒茶硒元素的高光谱遥感快速无损检测提供参考。[方法]以福鼎大白茶叶为研究对象,利用地物光谱仪测定不同硒浓度[0(CK)、2.5mg/L、5.0 mg/L、10.0 mg/L]处理后不同时间节点(第6天、第12天、第20天)的光谱数据,对其进行一阶微分、倒数对数和倒数对数的一阶微分数学变换处理,提取并分析可见光-近红外-短波红外谱段茶叶硒元素的反射光谱特征和敏感波段。[结果]叶面喷施不同浓度硒肥茶树叶片的光谱反射率曲线变化基本一致,但特定波长反射率差异明显。各处理在可见光、近红外、短波红外波段的反射率均较CK高,可见光范围内叶片反射率随施硒浓度增加而降低;近红外区随施硒浓度增加叶片的反射率起伏较大;短波红外范围叶片反射率与施硒浓度成正比。原始光谱经数学处理变换后提取的敏感波长分别为410 nm、415 nm、425 nm、448 nm、458 nm、463 nm、467 nm、469 nm、550 nm、709 nm、960 nm、1000 nm、1001 nm、1002 nm、1003 nm、1397 nm、1440 nm、1829 nm、1831 nm、1888 nm、2139 nm、2143 nm、2215 nm、2473 nm、2486 nm、2491 nm、2495 nm和2496 nm。[结论]叶面喷施硒肥对茶树叶片硒元素的光谱特征有一定影响,原始光谱经数学处理变换后共提取28条敏感波长。 展开更多
关键词 茶叶 光谱特征 VIS-nir-SIR 谱段信息 高光谱遥感
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基于临床可用荧光探针的NIR-II优质亚窗口的活体成像研究
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作者 李佳一 张沛锦 +1 位作者 夏启铭 钱骏 《红外与毫米波学报》 北大核心 2025年第5期654-662,共9页
近红外二区(the second near-infrared window,NIR-II,900~1880 nm)荧光成像具有信号背景比高、穿透深度大的优势,在生物医学领域具有广泛的应用前景。对NIR-II成像窗口的划分有利于优化成像过程,其中,NIRIIx(1400~1500 nm)成像窗口得... 近红外二区(the second near-infrared window,NIR-II,900~1880 nm)荧光成像具有信号背景比高、穿透深度大的优势,在生物医学领域具有广泛的应用前景。对NIR-II成像窗口的划分有利于优化成像过程,其中,NIRIIx(1400~1500 nm)成像窗口得益于其独特的水吸收,可以有效抑制散射背景,实现高对比度成像。文章通过仿真模拟和活体实验,系统评估了NIR-IIx窗口的成像潜力。为了更好地推进NIR-IIx荧光成像的临床转化,研究采用美国食品及药物管理局(FDA)批准的有机小分子染料吲哚菁绿(Indocyanine Green,ICG)作为荧光探针,利用其延伸至NIR-II的荧光发射拖尾,实现了高对比度和清晰度的小鼠血管和肠道的NIR-IIx成像。此外,研究还结合同样通过FDA认证的亚甲基蓝(Methylene Blue,MB),成功实现了高质量的NIR-II双通道成像,精准定位小鼠的血管和淋巴结。文章进一步挖掘了NIR-IIx在生物成像上的独特优势和临床应用的潜力,并为NIR-II荧光成像的临床转化提供了重要参考。 展开更多
关键词 荧光成像 nir-IIx 近红外二区 双通道成像 临床手术导航
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顾及Vis-NIR光谱指数时序统计特征的红层荒漠化场景分类
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作者 陈震 谢相建 +1 位作者 陈竹安 谭皓 《农业工程学报》 北大核心 2025年第9期165-174,共10页
荒漠化调查是区域土地修复、植被恢复与水土保持等农业整治工程的基础工作。而在东南丘陵区红层荒漠化的多光谱遥感监测中,仅依靠单一时相影像有限的光谱特征,难以表征和区分红层区复杂地表覆盖类型。针对该问题,该研究以湘赣北部交界... 荒漠化调查是区域土地修复、植被恢复与水土保持等农业整治工程的基础工作。而在东南丘陵区红层荒漠化的多光谱遥感监测中,仅依靠单一时相影像有限的光谱特征,难以表征和区分红层区复杂地表覆盖类型。针对该问题,该研究以湘赣北部交界的红层出露带为研究区,提出一种顾及Vis-NIR光谱指数时序统计特征的红层荒漠化场景多尺度分层分类方法。研究首先在典型地表覆盖敏感指数基础上,基于时序统计分析方法,增强红层目标与其他地物覆盖的可分性;然后结合面向对象影像分析技术和决策树分类方法,先后从像元尺度和对象尺度完成红层区纯净地物覆盖和荒漠化混合场景覆盖分类;最后与随机森林(random forest,RF)和支持向量机(support vector machine,SVM)分类模型进行对比分析。结果表明:敏感光谱指数的时序统计分析能够有效增强红层区典型覆盖场景的可分性;结合时序统计增强与面向对象空间优化的分层决策模型相较于RF和SVM两类分类模型总体分类精度提高了3.04%、3.52%;其中对裸岩的提取精确率为86.15%,召回率为89.31%,F1分数为0.88, F1分数相较于RF和SVM分别提高了4.76%和6.02%,有效地减少了裸岩错分漏分,提高了红层荒漠化场景分类精度。该研究为荒漠化遥感调查提供了一种简单有效的技术方案,也为赣西北红层荒漠化区域的土地修复等相关农业整治工作提供可靠的空间数据支持。 展开更多
关键词 遥感 决策树 特征优选 红层荒漠化 Vis-nir光谱指数 时序统计 空间优化
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Exploring the frontiers of plant health:Harnessing NIR fluorescence and surface-enhanced Raman scattering modalities for innovative detection 被引量:1
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作者 Shu Tian Wenxin Huang +5 位作者 Junrui Hu Huiling Wang Zhipeng Zhang Liying Xu Junrong Li Yao Sun 《Chinese Chemical Letters》 2025年第3期134-143,共10页
Plants play a crucial role in maintaining ecological balance and biodiversity.However,plant health is easily affected by environmental stresses.Hence,the rapid and precise monitoring of plant health is crucial for glo... Plants play a crucial role in maintaining ecological balance and biodiversity.However,plant health is easily affected by environmental stresses.Hence,the rapid and precise monitoring of plant health is crucial for global food security and ecological balance.Currently,traditional detection strategies for monitoring plant health mainly rely on expensive equipment and complex operational procedures,which limit their widespread application.Fortunately,near-infrared(NIR)fluorescence and surface-enhanced Raman scattering(SERS)techniques have been recently highlighted in plants.NIR fluorescence imaging holds the advantages of being non-invasive,high-resolution and real-time,which is suitable for rapid screening in large-scale scenarios.While SERS enables highly sensitive and specific detection of trace chemical substances within plant tissues.Therefore,the complementarity of NIR fluorescence and SERS modalities can provide more comprehensive and accurate information for plant disease diagnosis and growth status monitoring.This article summarizes these two modalities in plant applications,and discusses the advantages of multimodal NIR fluorescence/SERS for a better understanding of a plant’s response to stress,thereby improving the accuracy and sensitivity of detection. 展开更多
关键词 nir fluorescence SERS Plant biomarker detection Plant imaging PHYTOHORMONE
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Genomic selection for meat quality traits based on VIS/NIR spectral information 被引量:1
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作者 Xi Tang Lei Xie +8 位作者 Min Yan Longyun Li Tianxiong Yao Siyi Liu Wenwu Xu Shijun Xiao Nengshui Ding Zhiyan Zhang Lusheng Huang 《Journal of Integrative Agriculture》 2025年第1期235-245,共11页
The principle of genomic selection(GS) entails estimating breeding values(BVs) by summing all the SNP polygenic effects. The visible/near-infrared spectroscopy(VIS/NIRS) wavelength and abundance values can directly re... The principle of genomic selection(GS) entails estimating breeding values(BVs) by summing all the SNP polygenic effects. The visible/near-infrared spectroscopy(VIS/NIRS) wavelength and abundance values can directly reflect the concentrations of chemical substances, and the measurement of meat traits by VIS/NIRS is similar to the processing of genomic selection data by summing all ‘polygenic effects' associated with spectral feature peaks. Therefore, it is meaningful to investigate the incorporation of VIS/NIRS information into GS models to establish an efficient and low-cost breeding model. In this study, we measured 6 meat quality traits in 359Duroc×Landrace×Yorkshire pigs from Guangxi Zhuang Autonomous Region, China, and genotyped them with high-density SNP chips. According to the completeness of the information for the target population, we proposed 4breeding strategies applied to different scenarios: Ⅰ, only spectral and genotypic data exist for the target population;Ⅱ, only spectral data exist for the target population;Ⅲ, only spectral and genotypic data but with different prediction processes exist for the target population;and Ⅳ, only spectral and phenotypic data exist for the target population.The 4 scenarios were used to evaluate the genomic estimated breeding value(GEBV) accuracy by increasing the VIS/NIR spectral information. In the results of the 5-fold cross-validation, the genetic algorithm showed remarkable potential for preselection of feature wavelengths. The breeding efficiency of Strategies Ⅱ, Ⅲ, and Ⅳ was superior to that of traditional GS for most traits, and the GEBV prediction accuracy was improved by 32.2, 40.8 and 15.5%, respectively on average. Among them, the prediction accuracy of Strategy Ⅱ for fat(%) even improved by 50.7% compared to traditional GS. The GEBV prediction accuracy of Strategy Ⅰ was nearly identical to that of traditional GS, and the fluctuation range was less than 7%. Moreover, the breeding cost of the 4 strategies was lower than that of traditional GS methods, with Strategy Ⅳ being the lowest as it did not require genotyping.Our findings demonstrate that GS methods based on VIS/NIRS data have significant predictive potential and are worthy of further research to provide a valuable reference for the development of effective and affordable breeding strategies. 展开更多
关键词 VIS/nir genomic selection GEBV machine learning PIG meat quality
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Visible light-triggered NIR ratiometric fluorescent metal-free CO-releasing molecule for self-monitoring of CO delivery and effective cancer therapy
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作者 Shengyi Gong Guoqiang Feng 《Chinese Chemical Letters》 2025年第7期409-414,共6页
Cancer is a serious global health issue,and exploring effective treatment methods is of great significance for cancer prevention and control.Carbon monoxide(CO),as an important gas signaling molecule in the life syste... Cancer is a serious global health issue,and exploring effective treatment methods is of great significance for cancer prevention and control.Carbon monoxide(CO),as an important gas signaling molecule in the life system,has been proven to have good anti-cancer effects.However,how to controllably,safely,and effectively deliver CO to the tumor site for clinical treatment remains a challenge.Herein,a new metal-free CO-releasing molecule COR-XAC was developed for controlling CO release and cancer therapy.COR-XAC is based on the hybrid of 3-hydroxyl flavone and oxanthracene fluorophores,showing visible light-controlled CO-releasing properties and near-infrared(NIR)ratiometric fluorescence changes at 690 and 760 nm.COR-XAC shows low cytotoxicity and can be successfully applied to release CO in cells and tumors,and the CO-releasing and delivery process could be monitored by its own NIR ratiometric fluorescence changes.More importantly,the anti-cancer performance of COR-XAC was evaluated in 4T1 tumor mice,and it was found that COR-XAC plus light illumination showed excellent tumor inhibition effect,which provided a promising new effective method for cancer treatment. 展开更多
关键词 CO-releasing molecule RATIOMETRIC nir fluorescence CO delivery Cancer therapy
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Erbium-based hydrothermal YOF with stark sublevels for in vivo NIR II luminescence nanothermometer
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作者 Zhenghao Liu Ziyue Ju +2 位作者 Hanyu Liu Zhan Wang Ruichan Lv 《Journal of Innovative Optical Health Sciences》 2025年第3期99-108,共10页
Rare earth luminescent materials have attracted extensive attention in the biomedical field as noncontact temperature monitoring devices with microscopic resolution due to their properties in the visible and near-infr... Rare earth luminescent materials have attracted extensive attention in the biomedical field as noncontact temperature monitoring devices with microscopic resolution due to their properties in the visible and near-infrared regions.At the application level,it is required to have a certain temperature monitoring capability in the near-infrared region II window to enhance the tissue penetration depth.Here,two kinds of YOFs:Er^(3+),Yb^(3+)were prepared by co-precipitation and hydrothermal method,and the luminescence was enhanced by ion doping.An Er^(3+)-based ratiometric nanothermometer of ^(4)F_(9∕2)→4 I_(15∕2)(672nm,upconversion luminescence)to ^(4)I _(13∕2)→^(4) I_(15∕2)(1580nm/1566nm,NIR II downshifting luminescence)were designed with the Stark energy level.When doped with 2%Zn^(2+),the relative temperature sensitivity of YOF prepared by co-precipitation method was improved from 0.30%℃^(-1)(30℃)to 0.59%℃^(-1)(30℃),expanding its use as a temperature monitoring device possibility.The temperature sensitivity of YOF prepared by hydrothermal method was 1.01%℃^(-1)(30℃).Finally,the NIR II luminescence of the prepared nanothermometer was used as a control for temperature monitoring of heating sites in mice.The results showed that it can distinguish heating site from control site and no significant cytotoxicity or damage to the tissues was revealed,indicating its broad prospects in the biomedical field and other temperature monitoring scenarios in the future. 展开更多
关键词 Ratiometric nanothermometer upconversion luminescence nir II in vivo imaging
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H_(2)S and NIR light-driven nanomotors induce disulfidptosis for targeted anticancer therapy by enhancing disruption of tumor metabolic symbiosis
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作者 Shangqian Zhang Jiaxuan Li +7 位作者 Xuan Hu Zelong Chen Junliang Dong Chenhao Hu Shuang Chao Yinghua Lv Yuxin Pei Zhichao Pei 《Chinese Chemical Letters》 2025年第1期427-432,共6页
Disulfidptosis,a novel mechanism of programmed cell death through the disruption of tumor metabolic symbiosis(TMS),has showed tremendous potential in cancer therapy.However,the efficacy of disulfidptosis is limited by... Disulfidptosis,a novel mechanism of programmed cell death through the disruption of tumor metabolic symbiosis(TMS),has showed tremendous potential in cancer therapy.However,the efficacy of disulfidptosis is limited by poor permeability of drugs in solid tumors.Herein,hydrogen sulfide(H_(2)S)and nearinfrared(NIR)light-driven nanomotors(denoted as HGPP)have been constructed to efficiently penetrate tumors and induce disulfidptosis.HGPP demonstrate glutathione(GSH)-responsive release of H_(2)S,which combined with NIR light-induced photothermal effect drive HGPP movement to facilitate deep tumor penetration.The released H_(2)S induces tumor acidosis and disrupts TMS,where disulfide accumulation following cell starvation leads to disulfidptosis.In addition,HGPP induce hepatoma specific cellular uptake and catalyze the conversion of glucose and oxygen to produce hydrogen peroxide(H_(2)O_(2)),leading to glucose starvation.Overall,this study has developed a multifunctional Janus nanomotor that provides a novel strategy for disulfidptosis-based solid tumor therapy. 展开更多
关键词 H_(2)S nir light NANOMOTORS Disulfidptosis Tumor metabolic symbiosis
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NIR driven catalytic enhanced acute lung injury therapy by using polydopamine@Co nanozyme via scavenging ROS
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作者 Xiaoshuai Wu Bailei Wang +12 位作者 Yichen Li Xiaoxuan Guan Mingjing Yin Wenquan Lv Yin Chen Fei Lu Tao Qin Huyang Gao Weiqian Jin Yifu Huang Cuiping Li Ming Gao Junyu Lu 《Chinese Chemical Letters》 2025年第2期309-315,共7页
Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herei... Acute lung injury(ALI)was characterized by excessive reactive oxygen species(ROS)levels and inflammatory response in the lung.Scavenging ROS could inhibit the excessive inflammatory response,further treating ALI.Herein,we designed a novel nanozyme(P@Co)comprised of polydopamine(PDA)nanoparticles(NPs)loading with ultra-small Co,combining with near infrared(NIR)irradiation,which could efficiently scavenge intracellular ROS and suppress inflammatory responses against ALI.For lipopolysaccharide(LPS)induced macrophages,P@Co+NIR presented excellent antioxidant and anti-inflammatory capacities through lowering intracellular ROS levels,decreasing the expression levels of interleukin-6(IL-6)and tumor necrosis factor-α(TNF-α)as well as inducing macrophage M2 directional polarization.Significantly,it displayed the outstanding activities of lowering acute lung inflammation,relieving diffuse alveolar damage,and up-regulating heat shock protein 70(HSP70)expression,resulting in synergistic enhanced ALI therapy effect.It offers a novel strategy for the clinical treatment of ROS related diseases. 展开更多
关键词 Acute lung injury nir driven Nanozyme ROS scavenging M2 directional polarization
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Extended π-conjugated systems by external ligand-assisted C-H olefination of heterocycles: Facile access to single-molecular white-light-emitting and NIR fiuorescence materials
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作者 Ruike Hu Kangmin Wang +4 位作者 Junxiang Liu Jingxian Zhang Guoliang Yang Liqiu Wan Bijin Li 《Chinese Chemical Letters》 2025年第4期131-138,共8页
The design and synthesis of a novel π-conjugated fiuorescent framework by external ligand-assisted C-H olefination of heterocycles with excellent regioselectivity and broad substrate scope are reported herein.These n... The design and synthesis of a novel π-conjugated fiuorescent framework by external ligand-assisted C-H olefination of heterocycles with excellent regioselectivity and broad substrate scope are reported herein.These novel fiuorescent materials could present full-color-tunable emissions with large Stokes shifts. Furthermore, the protocol provides an opportunity to rapidly screen novel organic single-molecule whitelight materials with high fiuorescence quantum yields. The robust organic and low-cost white lightemitting diodes could rapidly be fabricated using the white-light-emitting material. Experimental data and theoretical calculations indicate that in the white-light dual emission the relatively short wavelength from high-lying singlet state emission and the relatively long wavelength from low-lying singlet state emission. The anti-Kasha dual-emission systems will provide a foundation for the development and application of organic single-molecule white light materials, effectively promoting the development and innovation of luminescent materials. In addition, this method demonstrated its potential application in the synthesis of new near-infrared(NIR) fiuorescence materials with large Stokes shifts based on the olefination of heterocycles. 展开更多
关键词 π-Conjugated fiuorescent framework C—H olefination Organic single-molecule white-light materials HETEROCYCLES nir fiuorescence materials
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Cyanine-tagged albumin facilitates high-performance NIR-II biomedical imaging
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作者 Ze-Tao Dang Shou-Jun Zhu 《Biomedical Engineering Communications》 2025年第3期1-3,共3页
The emerging NIR-II imaging modality is promising for real-time visualization of living systems and multiple disease diagnoses,particularly through its enhanced tissue penetration and superior spatial resolution[1,2].... The emerging NIR-II imaging modality is promising for real-time visualization of living systems and multiple disease diagnoses,particularly through its enhanced tissue penetration and superior spatial resolution[1,2].Cyanine dyes possess the advantages of low administration dosage,high biocompatibility,and strong fluorescence emission intensity[3].Cyanine dyes can be easily structurally modified through molecular engineering methods,while the large hydrophobic conjugation systems hinder further in vivo imaging application.The traditional surfactant encapsulation strategy cannot effectively solve the aggregation caused-quenching issue of the dyes in aqueous solutions and may even mask their reaction active sites[4].Due to the special hydrophobic pocket to act as a probe carrier and the ability to serve as the pan-marker for multiple diseases,albumin is chosen as the preferred binding protein for cyanine dyes[5].Albumin interacts with cyanine dyes through a“hydrophobic pocket”and further improves its properties such as water solubility,biosafety,and fluorescence quantum yield.Cyanine dyes can modify the binding efficiency with albumin through structural design and regulate the targeting performance.This means that cyanine-tagged albumin can respond to pathological changes caused by different diseases and monitor the disease process in real time with high contrast through NIR-II fluorescence signals.Further development of cyanine-tagged albumin probes is helpful for in-depth comprehension of the binding mechanism and guiding the directed synthesis of cyanine molecules with specific protein binding behaviors and optical properties,thereby achieving precise targeting and high-performance NIR-II bioimaging of specific diseases.This point is essential for the design,preparation,and even clinical translation of NIR-II targeting dye molecules in precise diagnosis and treatment. 展开更多
关键词 living systems Cyanine dyes molecular engineering methodswhile nir II imaging ALBUMIN hydrophobic conjugation systems superior spatial resolution cyanine dyes structurally modified
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A new class of NIR-II luminescent nanoprobes via Ho^(3+) sensitization for deep-tissue multiplexed imaging
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作者 Yitong Shi Dengfeng Yang +1 位作者 Wei Zheng Xueyuan Chen 《Chinese Journal of Structural Chemistry》 2025年第6期3-5,共3页
Lanthanide(Ln^(3+))-doped luminescent nanocrystals(NCs)with excitation and emission in the second near-infrared biological window(NIRII,1000-1700 nm)have attracted considerable attention in the fields of deep-tissue b... Lanthanide(Ln^(3+))-doped luminescent nanocrystals(NCs)with excitation and emission in the second near-infrared biological window(NIRII,1000-1700 nm)have attracted considerable attention in the fields of deep-tissue bioimaging and non-invasive biodetection,owing to their superior advantages including good photochemical stability,sharp emission peaks,large penetration depth,and high signal-to-noise ratio[1].Conventionally,Yb3t-and Nd3t-sensitized NCs have been utilized as NIR-II luminescent nanoprobes for in vivo bioimaging upon excitation with 980 and 808 nm diode laser,respectively[2]. 展开更多
关键词 Deep tissue multiplexed imaging nir II luminescent nanoprobes Emission peaks Photochemical stability Signal noise ratio Ho sensitization lanthanide doped luminescent nanocrystals Penetration depth
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秸秆原料堆肥过程参数的NIRS模型转移研究
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作者 葛辰俊 魏鲁誉 +3 位作者 杨增玲 黄圆萍 史卓林 韩鲁佳 《中国农业大学学报》 北大核心 2025年第7期1-13,共13页
为提高秸秆好氧堆肥近红外分析模型在不同光谱设备下的通用性和准确性,以玉米秸秆和奶牛粪便为原料,进行静态槽式好氧堆肥和膜覆盖好氧堆肥,采集堆肥全过程样本,分析含水率、总氮、总碳、有机质含量共4个堆肥过程参数,分别使用台式光谱... 为提高秸秆好氧堆肥近红外分析模型在不同光谱设备下的通用性和准确性,以玉米秸秆和奶牛粪便为原料,进行静态槽式好氧堆肥和膜覆盖好氧堆肥,采集堆肥全过程样本,分析含水率、总氮、总碳、有机质含量共4个堆肥过程参数,分别使用台式光谱仪和手持便携式光谱仪采集近红外光谱数据,并建立相关模型,通过直接校正算法(Direct standardization,DS)和典型相关分析算法(Canonical correlation analysis,CCA)实现台式和便携式光谱仪之间的共享。结果表明该2种算法均可用于堆肥过程参数的模型转移,但DS算法的表现更优。其中:含水率、总氮模型在使用模型转移算法后具有良好表现,便携式光谱仪的含水率模型使用模型转移算法后相对偏差误差RPD可达2.62,总氮含量模型RPD可达2.00;总碳、有机质含量模型虽未达到良好水平,但相较未使用模型转移算法有较大提升,对应模型的RPD分别由0.33、0.39提升到1.78、1.76。此外,本研究的2种算法对于不同仪器间的光谱差异进行了有效校正,降低了近红外光谱技术用于堆肥时仪器差异的限制,提高了不同光谱仪的共享性。综上,本研究可为堆肥过程现场高频次检测提供新解决策略。 展开更多
关键词 好氧堆肥 堆肥过程参数 近红外光谱 模型转移
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可见光/NIR-Ⅰ/NIR-Ⅱ三波段5 mm腹腔镜光学系统设计
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作者 孟祥翔 贾成园 +1 位作者 邱明杰 李占鑫 《红外与激光工程》 北大核心 2025年第6期185-195,共11页
5mm腹腔镜因其镜杆细、占用空间小在多种手术场景下有着广泛应用。为了提升5 mm腹腔镜在近红外波段的病灶探测能力,设计了一款可见光/近红外一区(Near Infrared Region I,NIR-Ⅰ)/近红外二区(Near Infrared RegionⅡ,NIR-Ⅱ)三波段复合... 5mm腹腔镜因其镜杆细、占用空间小在多种手术场景下有着广泛应用。为了提升5 mm腹腔镜在近红外波段的病灶探测能力,设计了一款可见光/近红外一区(Near Infrared Region I,NIR-Ⅰ)/近红外二区(Near Infrared RegionⅡ,NIR-Ⅱ)三波段复合成像内窥镜,并进行了病灶探测深度仿真。为保证兼容性,所设计腹腔镜的光学观察镜部分和摄像适配器部分单独校正像差。光学观察镜部分在486~1700 nm宽波段消色差,实现可见光、NIR-Ⅰ、NIR-Ⅱ三波段共焦面设计。摄像适配器部分进行两次分光,在入射平行光处分成1000~1700 nm和486~900 nm两支路,其中1000~1700 nm支路接InGaAs相机实现NIR-Ⅱ成像;486~900 nm支路接传统荧光内窥镜摄像系统并在成像芯片前二次分光实现可见光和NIR-Ⅰ成像。该系统入瞳直径0.3 mm、视场角80°、最大相对畸变≤20.13%。利用TracePro软件仿真分析了该腹腔镜在NIR-Ⅰ和NIR-Ⅱ波段对肿瘤病灶的探测能力,当以总功率2 W、发射半角45°、波长808 nm的入射光激发位于组织体内深度4 mm、半径0.5 mm的肿瘤时,NIR-Ⅰ波段探测信噪比为3.14 dB,NIR-Ⅱ波段在探测器制冷-20℃时信噪比为5.52 dB,制冷-80℃时信噪比为6.95 dB。结果表明,可见光/NIR-Ⅰ/NIR-Ⅱ三波段复合成像可提升5 mm腹腔镜对病灶的探测性能。 展开更多
关键词 光学设计 内窥镜 近红外一区 近红外二区
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miR⁃138⁃5p靶向Nir1调控胶质瘤细胞的侵袭
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作者 陈萍萍 平勇 +5 位作者 赵一诺 梁粉花 宋佰慧 王玲 李慧玲 孙树艳 《循证医学》 2024年第1期37-43,共7页
目的 探讨miR-138-5p与PYK2 N端结构域相互作用受体1(PYK2 N-terminal domain-interacting receptor 1,Nir1)之间的关系并判断其是否通过与Nir1结合影响胶质瘤的侵袭。方法 比较不同胶质瘤细胞系中miR-138-5p表达水平及其对胶质瘤细胞U... 目的 探讨miR-138-5p与PYK2 N端结构域相互作用受体1(PYK2 N-terminal domain-interacting receptor 1,Nir1)之间的关系并判断其是否通过与Nir1结合影响胶质瘤的侵袭。方法 比较不同胶质瘤细胞系中miR-138-5p表达水平及其对胶质瘤细胞U251和H4中Nir1蛋白的影响、转染后胶质瘤细胞侵袭能力,检测miR-138-5p能否与Nir1靶向结合。结果 低侵袭人胶质瘤H4细胞中miR-138-5p的水平显著高于高侵袭性的胶质瘤U251、LN229和U87细胞(P<0.05);在U251、H4细胞中,miR-138-5p过表达组Nir1蛋白表达量较其对照组(miR-negative control,miR-NC)降低;miR-138-5p抑制组中Nir1蛋白表达量较其对照组(inhibitor NC)升高。然而,miR-138-5p过表达组中Nir1的mRNA水平较其对照组无明显改变(P>0.05)。miR-138-5p过表达组穿过基底膜小孔的U251、H4细胞数明显少于其对照组(P<0.05)。miR-138-5p过表达显著降低Nir1-3’-UTR的荧光素酶活性。结论 胶质瘤细胞中miR-138-5p与Nir1结合,可通过降低Nir1的翻译、减少Nir1蛋白的表达抑制胶质瘤细胞的侵袭能力。 展开更多
关键词 胶质瘤 侵袭 miR⁃138⁃5p nir1
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复合垂直流人工湿地基质理化性质对nirS和nirK型反硝化菌多样性的影响 被引量:1
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作者 赵伟 朱四喜 +3 位作者 夏国栋 高宁 赵斌 王众 《水生态学杂志》 CSCD 北大核心 2024年第2期132-140,共9页
深入研究复合垂直流人工湿地基质理化性质及其对相关脱氮反硝化微生物的影响,可为解析人工湿地污水处理及提高脱氮效率提供理论依据。2020年12月采集贵州喀斯特地区复合垂直流人工湿地4口池(一级垂直流下行池、一级垂直流上行池、二级... 深入研究复合垂直流人工湿地基质理化性质及其对相关脱氮反硝化微生物的影响,可为解析人工湿地污水处理及提高脱氮效率提供理论依据。2020年12月采集贵州喀斯特地区复合垂直流人工湿地4口池(一级垂直流下行池、一级垂直流上行池、二级垂直流下行池、二级垂直流上行池)的基质样品,用Illumina高通量测序技术获得反硝化功能基因序列,分析其种群组成和多样性特征,并采用冗余分析揭示反硝化菌群落与基质理化性质之间的相关性。结果表明,复合垂直流人工湿地中4口池的基质理化性质存在显著差异;pH在4口池中均呈中性,溶解氧(DO)呈先下降后升高趋势,下行池的基质电导率(EC)均比上行池要高;总氮(TN)、总磷(TP)含量随着人工湿地梯级呈显著下降趋势,未出现厌氧现象;NO_(3)^(-)-N和NH_(4)^(+)-N含量在二级垂直流下行池中大量积累并达到峰值。在多样性分析中,nirS、nirK型反硝化菌丰度随着人工湿地梯级呈先降低后升高的趋势,多样性随人工湿地级数逐渐降低,且下行池丰度多样性显著高于上行池。基质中nirS型反硝化菌共5门9属,nirS型为6门14属,变形菌门是nirS、nirK型反硝化菌群的共同优势菌门,相对丰度为55.36%~65.72%、30.06%~45.66%。nirS、nirK型反硝化菌共有OTUs数分别为392、245,并与反硝化菌群OTUs数目趋势一致,从多角度表明nirS型反硝化菌群丰度明显高于nirK型,且共有OTUs占有率高达41.6%和41.7%,表明各级池中反硝化菌群相似度较高。冗余分析表明基质中nirS和nirK反硝化菌群的构建主要受pH、NH4+-N、DO、TP、TN影响,且nirS型对pH、nirK型对NH4+-N的响应更为强烈。 展开更多
关键词 nirS和nirK型 反硝化菌 Illumina高通量测序 冗余分析 复合垂直流人工湿地
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基于RGB-NIR滤波阵列的引入权重系数的加权引导滤波去马赛克方法
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作者 吴鑫 徐宝腾 +2 位作者 刘家林 周伟 杨西斌 《光子学报》 EI CAS CSCD 北大核心 2024年第9期40-50,共11页
针对RGB-NIR传感器多光谱成像技术中的去马赛克问题,提出了一种引入权重系数的加权引导滤波去马赛克算法。算法以残差插值为框架,引入加权引导滤波代替引导滤波,通过边缘感知权重因子实现对边缘的检测,提高引导滤波在边缘处的性能。算... 针对RGB-NIR传感器多光谱成像技术中的去马赛克问题,提出了一种引入权重系数的加权引导滤波去马赛克算法。算法以残差插值为框架,引入加权引导滤波代替引导滤波,通过边缘感知权重因子实现对边缘的检测,提高引导滤波在边缘处的性能。算法使用G通道图像作为引导图,首先进行G通道图像的插值,然后通过加权引导滤波的方法插值出R、B、NIR通道的图像。此外,为了解决在引导滤波中计算线性系数时采用简单的平均值的问题,引入权重系数,并通过加权平均的方式计算得到更准确的线性系数。在TokyoTech数据集以及实际器件上测试了该算法。在数据集的实验上,提出的算法比现有的高性能算法在彩色图像和红外图像上峰值信噪比分别高0.38 dB和0.88 dB;在实际器件实验中,不论是在红外光源打开还是关闭的情况下,所提出的算法在多个场景下表现出最低的平均NIQE指标。此外,在红外光源变动前后,提出的算法所得到的图像的平均NIQE变化也是最小的。实验结果表明,该算法的性能优于对比的算法,并且拥有更好的鲁棒性。 展开更多
关键词 RGB-nir 去马赛克 加权引导滤波 权重系数 鲁棒性
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基于双路AOTF-NIR的静态目标DoLP探测系统研究与设计
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作者 孙德刚 高天学 +4 位作者 葛宾 马安会 郝萍萍 赵兴娜 王志斌 《电子器件》 CAS 2024年第4期917-921,共5页
双路宽光谱AOTF-NIR器件在遥感偏振成像系统中得到广泛应用,系统采用双路AOTF-NIR及四路红外CCD相机相结合的方式来获取静态目标物光谱图像,通过上位机控制AOTF-NIR的入射角度及双路射频驱动频率实现900 nm~1 700 nm的DoLP光谱成像,同... 双路宽光谱AOTF-NIR器件在遥感偏振成像系统中得到广泛应用,系统采用双路AOTF-NIR及四路红外CCD相机相结合的方式来获取静态目标物光谱图像,通过上位机控制AOTF-NIR的入射角度及双路射频驱动频率实现900 nm~1 700 nm的DoLP光谱成像,同时从晶体阻抗匹配角度分析了双路AOTF-NIR宽带匹配新方法,给出了一种衍射效率峰值可达73%、光谱成像清晰度较高的带通型匹配网络。通过在1 120 nm的0°,45°,90°,135°衍射光强度与DoLP成像实验表明该系统可有效获取静态目标物在强度成像系统无法获得的结构特征等信息,可为近红外遥感成像与识别技术提供一定的理论依据。 展开更多
关键词 双路AOTF-nir 偏振成像 宽带匹配 衍射效率
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可NIR-II荧光成像的多功能化疗栓塞微球PLGA@Re-DOX的制备及其在肝癌荧光手术导航中的应用
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作者 李雪晓 谢旎 +3 位作者 王晓彤 殷佳慧 李漫琳 段广新 《现代生物医学进展》 CAS 2024年第18期3415-3421,共7页
目的:开发具备近红外二区(Near-Infrared II,NIR-II)荧光成像性能的多功能化疗栓塞微球,评估其在肝癌NIR-II荧光手术导航中的应用效果。方法:制备NaGdF_(4):Nd@NaGdF_(4)纳米颗粒(Re NPs)和聚乳酸-羟基乙酸共聚物(Polylactic-co-glycoli... 目的:开发具备近红外二区(Near-Infrared II,NIR-II)荧光成像性能的多功能化疗栓塞微球,评估其在肝癌NIR-II荧光手术导航中的应用效果。方法:制备NaGdF_(4):Nd@NaGdF_(4)纳米颗粒(Re NPs)和聚乳酸-羟基乙酸共聚物(Polylactic-co-glycolic Acid,PLGA)基微球,利用透射电子显微镜(Transmission Electron Microscope,TEM)和荧光光谱仪分析Re NPs形貌和荧光性能。PLGA基微球的形貌、元素组成通过光学显微镜、扫描电子显微镜(Scanning Electron Microscope,SEM)、X射线能谱分析(Energy Dispersive Spectroscopy,EDS)进行表征。利用紫外光谱分仪测定PLGA微球的阿霉素(Doxorubicin,DOX)装载和DOX释放情况。细胞增殖-毒性实验(Cell Counting Kit-8,CCK-8)和溶血实验来评估其生物相容性。利用NIR-II成像系统分析PLGA@Re-DOX微球的成像效果和荧光稳定性。通过肝动脉插管将PLGA@Re-DOX微球递送至大鼠肝癌部位,观察其对NIR-II荧光成像效果。结果:Re NPs展现出良好的单分散性和均一球形结构,平均粒径为9.3±0.4 nm,并具备优异的NIR-II荧光成像性能。PLGA、PLGA@Re-DOX微球尺寸分别为294±7μm、288±13μm,具有高度的均一性。PLGA微球具有良好的生物相容性,其对细胞存活率和溶血率与对照组相比没有显著统计差异(P>0.05)。此外,DOX包封率可达2.5%,能缓慢释放药物。PLGA@Re-DOX微球具有良好的肝内外NIR-II荧光成像效果和优异的荧光稳定性,经肝动脉递送后进行NIR-II荧光成像可以清晰地显示肿瘤边缘。结论:制备的PLGA@Re-DOX微球可有望实现对肝癌的NIR-II荧光成像和荧光手术导航。 展开更多
关键词 PLGA微球 nir-II荧光成像 肝癌 手术导航
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