Author
Xiaoyuan Chen
Other affiliations: Brown University, University of Southern California, Uniformed Services University of the Health Sciences ...read more
Bio: Xiaoyuan Chen is an academic researcher from National University of Singapore. The author has contributed to research in topics: Physics & Photothermal therapy. The author has an hindex of 149, co-authored 994 publications receiving 89870 citations. Previous affiliations of Xiaoyuan Chen include Brown University & University of Southern California.
Topics: Physics, Photothermal therapy, Medicine, Molecular imaging, In vivo
Papers published on a yearly basis
Papers
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TL;DR: It is shown that single-walled carbon nanotubes conjugated with cyclic Arg-Gly-Asp (RGD) peptides can be used as a contrast agent for photoacoustic imaging of tumours and intravenous administration showed eight times greater photoac acoustic signal in the tumour than mice injected with non-targeted nanot tubes.
Abstract: Photoacoustic imaging of living subjects offers higher spatial resolution and allows deeper tissues to be imaged compared with most optical imaging techniques1,2,3,4,5,6,7. As many diseases do not exhibit a natural photoacoustic contrast, especially in their early stages, it is necessary to administer a photoacoustic contrast agent. A number of contrast agents for photoacoustic imaging have been suggested previously8,9,10,11,12,13,14,15, but most were not shown to target a diseased site in living subjects. Here we show that single-walled carbon nanotubes conjugated with cyclic Arg-Gly-Asp (RGD) peptides can be used as a contrast agent for photoacoustic imaging of tumours. Intravenous administration of these targeted nanotubes to mice bearing tumours showed eight times greater photoacoustic signal in the tumour than mice injected with non-targeted nanotubes. These results were verified ex vivo using Raman microscopy. Photoacoustic imaging of targeted single-walled carbon nanotubes may contribute to non-invasive cancer imaging and monitoring of nanotherapeutics in living subjects16. Photoacoustic imaging offers higher spatial resolution than most optical imaging techniques, but contrast agents are needed because many diseases in their early stages do not display a natural photoacoustic contrast. Using single-walled carbon nanotubes conjugated with a peptide as a contrast agent allows the non-invasive photoacoustic imaging of tumours in animals.
1,169 citations
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TL;DR: It is highly expected that deep PDT will be developed as a versatile, depth/oxygen-independent and minimally invasive strategy for treating a variety of malignant tumours at deep locations.
Abstract: Photodynamic therapy (PDT) has been applied to treat a wide range of medical conditions, including wet age-related macular degeneration psoriasis, atherosclerosis, viral infection and malignant cancers. However, the tissue penetration limitation of excitation light hinders the widespread clinical use of PDT. To overcome this “Achilles' heel”, deep PDT, a novel type of phototherapy, has been developed for the efficient treatment of deep-seated diseases. Based on the different excitation sources, including near-infrared (NIR) light, X-ray radiation, and internal self-luminescence, a series of deep PDT techniques have been explored to demonstrate the advantages of deep cancer therapy over conventional PDT excited by ultraviolet-visible (UV-Vis) light. In particular, the featured applications of deep PDT, such as organelle-targeted deep PDT, hypoxic deep PDT and deep PDT-involved multimodal synergistic therapy are discussed. Finally, the future development and potential challenges of deep PDT are also elucidated for clinical translation. It is highly expected that deep PDT will be developed as a versatile, depth/oxygen-independent and minimally invasive strategy for treating a variety of malignant tumours at deep locations.
1,087 citations
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TL;DR: Functionalization of SWNTs by branched polyethylene-glycol (PEG) chains was developed, enabling thus far the longest SWNT blood circulation up to 1 day, relatively low uptake in the reticuloendothelial system (RES), and near-complete clearance from the main organs in ≈2 months.
Abstract: Carbon nanotubes are promising new materials for molecular delivery in biological systems. The long-term fate of nanotubes intravenously injected into animals in vivo is currently unknown, an issue critical to potential clinical applications of these materials. Here, using the intrinsic Raman spectroscopic signatures of single-walled carbon nanotubes (SWNTs), we measured the blood circulation of intravenously injected SWNTs and detect SWNTs in various organs and tissues of mice ex vivo over a period of three months. Functionalization of SWNTs by branched polyethylene-glycol (PEG) chains was developed, enabling thus far the longest SWNT blood circulation up to 1 day, relatively low uptake in the reticuloendothelial system (RES), and near-complete clearance from the main organs in ≈2 months. Raman spectroscopy detected SWNT in the intestine, feces, kidney, and bladder of mice, suggesting excretion and clearance of SWNTs from mice via the biliary and renal pathways. No toxic side effect of SWNTs to mice was observed in necropsy, histology, and blood chemistry measurements. These findings pave the way to future biomedical applications of carbon nanotubes.
1,052 citations
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TL;DR: A self-reinforcing CDT nanoagent based on MnO2 is reported that has both Fenton-like Mn2+ delivery and GSH depletion properties and allows MS@MnO2 NPs to achieve MRI-monitored chemo-chemodynamic combination therapy.
Abstract: Chemodynamic therapy (CDT) utilizes iron-initiated Fenton chemistry to destroy tumor cells by converting endogenous H2 O2 into the highly toxic hydroxyl radical (. OH). There is a paucity of Fenton-like metal-based CDT agents. Intracellular glutathione (GSH) with . OH scavenging ability greatly reduces CDT efficacy. A self-reinforcing CDT nanoagent based on MnO2 is reported that has both Fenton-like Mn2+ delivery and GSH depletion properties. In the presence of HCO3- , which is abundant in the physiological medium, Mn2+ exerts Fenton-like activity to generate . OH from H2 O2 . Upon uptake of MnO2 -coated mesoporous silica nanoparticles (MS@MnO2 NPs) by cancer cells, the MnO2 shell undergoes a redox reaction with GSH to form glutathione disulfide and Mn2+ , resulting in GSH depletion-enhanced CDT. This, together with the GSH-activated MRI contrast effect and dissociation of MnO2 , allows MS@MnO2 NPs to achieve MRI-monitored chemo-chemodynamic combination therapy.
1,008 citations
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University of Marburg1, University of Erlangen-Nuremberg2, Rovira i Virgili University3, University of Göttingen4, Max Planck Society5, University of California, Los Angeles6, International School for Advanced Studies7, University of Melbourne8, University of Trieste9, Ikerbasque10, University of Toronto11, Nanyang Technological University12, National Institutes of Health13, Stanford University14, Shanghai Jiao Tong University15, Tongji University16, University of Seville17, Karolinska Institutet18, Drexel University19, Sichuan University20, Rice University21, Northwestern University22, University of Basel23, Zhejiang University24, Heidelberg University25, University of Tokyo26, Harvard University27, University of Utah28, University of Michigan29, Swiss Federal Laboratories for Materials Science and Technology30, Seoul National University31, Saarland University32, Columbia University33, Chinese Academy of Sciences34, Kazan Federal University35, Emory University36, University of California, Irvine37, Autonomous University of Barcelona38, University of Massachusetts Amherst39, Pennsylvania State University40, Ghent University41, Imperial College London42, National Tsing Hua University43, South China University of Technology44, University of Ulm45, Hebrew University of Jerusalem46, Huazhong University of Science and Technology47, Peking University48
TL;DR: An overview of recent developments in nanomedicine is provided and the current challenges and upcoming opportunities for the field are highlighted and translation to the clinic is highlighted.
Abstract: The design and use of materials in the nanoscale size range for addressing medical and health-related issues continues to receive increasing interest. Research in nanomedicine spans a multitude of areas, including drug delivery, vaccine development, antibacterial, diagnosis and imaging tools, wearable devices, implants, high-throughput screening platforms, etc. using biological, nonbiological, biomimetic, or hybrid materials. Many of these developments are starting to be translated into viable clinical products. Here, we provide an overview of recent developments in nanomedicine and highlight the current challenges and upcoming opportunities for the field and translation to the clinic.
926 citations
Cited by
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TL;DR: There is, I think, something ethereal about i —the square root of minus one, which seems an odd beast at that time—an intruder hovering on the edge of reality.
Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.
Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …
33,785 citations
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28,685 citations
28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。
18,940 citations
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TL;DR: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties are equally important.
Abstract: The interest in nanoscale materials stems from the fact that new properties are acquired at this length scale and, equally important, that these properties * To whom correspondence should be addressed. Phone, 404-8940292; fax, 404-894-0294; e-mail, mostafa.el-sayed@ chemistry.gatech.edu. † Case Western Reserve UniversitysMillis 2258. ‡ Phone, 216-368-5918; fax, 216-368-3006; e-mail, burda@case.edu. § Georgia Institute of Technology. 1025 Chem. Rev. 2005, 105, 1025−1102
6,852 citations