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1.
The NIR light‐induced imaging‐guided cancer therapy is a promising route in the targeting cancer therapy field. However, up to now, the existing single‐modality light‐induced imaging effects are not enough to meet the higher diagnosis requirement. Thus, the multifunctional cancer therapy platform with multimode light‐induced imaging effects is highly desirable. In this work, captopril stabilized‐Au nanoclusters Au25(Capt)18?(Au25) are assembled into the mesoporous silica shell coating outside of Nd3+‐sensitized upconversion nanoparticles (UCNPs) for the first time. The newly formed Au25 shell exhibits considerable photothermal effects, bringing about the photothermal imaging and photoacoustic imaging properties, which couple with the upconversion luminescence imaging. More importantly, the three light‐induced imaging effects can be simultaneously achieved by exciting with a single NIR light (808 nm), which is also the triggering factor for the photothermal and photodynamic cancer therapy. Besides, the nanoparticles can also present the magnetic resonance and computer tomography imaging effects due to the Gd3+ and Yb3+ ions in the UCNPs. Furthermore, due to the photodynamic and the photothermal effects, the nanoparticles possess efficient in vivo tumor growth inhibition under the single irradiation of 808 nm light. The multifunctional cancer therapy platform with multimode imaging effects realizes a true sense of light‐induced imaging‐guided cancer therapy.  相似文献   

2.
Multifunctional nanodrugs integrating multiple therapeutic and imaging functions may find tremendous biomedical applications. However, the development of a simple yet potent theranostic nanosystem with a high payload and microenvironment responsiveness enhancing imaging‐guided cancer therapy is still a great challenge. Herein, a kind of MnCO‐entrapped mesoporous polydopamine nanoparticles are developed, which reach a 1.5 mg payload per gram carrier and exhibit marked theranostic capability through effective CO/Mn2+ generation and photothermal conversion inside the H+ and H2O2‐enriched tumor microenvironment, for a magnetic resonance/photoacoustic bimodal imaging‐guided tumor therapy. The multifunctional nanosystem exhibits a biocompatibility highly desirable for in vivo application and superior performance in inhibiting tumor growth and recurrence via combination CO and photothermal therapy.  相似文献   

3.
A novel multifunctional drug‐delivery platform is developed based on cholesteryl succinyl silane (CSS) nanomicelles loaded with doxorubicin, Fe3O4 magnetic nanoparticles, and gold nanoshells (CDF‐Au‐shell nanomicelles) to combine magnetic resonance (MR) imaging, magnetic‐targeted drug delivery, light‐triggered drug release, and photothermal therapy. The nanomicelles show improved drug‐encapsulation efficiency and loading level, and a good response to magnetic fields, even after the formation of the gold nanoshell. An enhancement for T2‐weighted MR imaging is observed for the CDF‐Au‐shell nanomicelles. These nanomicelles display surface plasmon absorbance in the near‐infrared (NIR) region, thus exhibiting an NIR (808 nm)‐induced temperature elevation and an NIR light‐triggered and stepwise release behavior of doxorubicin due to the unique characteristics of the CSS nanomicelles. Photothermal cytotoxicity in vitro confirms that the CDF‐Au‐shell nanomicelles cause cell death through photothermal effects only under NIR laser irradiation. Cancer cells incubated with CDF‐Au‐shell nanomicelles show a significant decrease in cell viability only in the presence of both NIR irradiation and a magnetic field, which is attributed to the synergetic effects of the magnetic‐field‐guided drug delivery and the photothermal therapy. Therefore, such multicomponent nanomicelles can be developed as a smart and promising nanosystem that integrates multiple capabilities for effective cancer diagnosis and therapy.  相似文献   

4.
The ideal theranostic nanoplatform for tumors is a single nanoparticle that has a single semiconductor or metal component and contains all multimodel imaging and therapy abilities. The design and preparation of such a nanoparticle remains a serious challenge. Here, with FeS2 as a model of a semiconductor, the tuning of vacancy concentrations for obtaining “all‐in‐one” type FeS2 nanoparticles is reported. FeS2 nanoparticles with size of ≈30 nm have decreased photoabsorption intensity from the visible to near‐infrared (NIR) region, due to a low S vacancy concentration. By tuning their shape/size and then enhancing the S vacancy concentration, the photoabsorption intensity of FeS2 nanoparticles with size of ≈350 nm (FeS2‐350) goes up with the increase of the wavelength from 550 to 950 nm, conferring the high NIR photothermal effect for thermal imaging. Furthermore, this nanoparticle has excellent magnetic properties for T2‐weighted magnetic resonance imaging (MRI). Subsequently, FeS2‐350 phosphate buffer saline (PBS) dispersion is injected into the tumor‐bearing mice. Under the irradiation of 915‐nm laser, the tumor can be ablated and the metastasis lesions in liver suffer significant inhibition. Therefore, FeS2‐350 has great potential to be used as novel “all‐in‐one” multifunctional theranostic nanoagents for MRI and NIR dual‐modal imaging guided NIR‐photothermal ablation therapy (PAT) of tumors.  相似文献   

5.
Copper‐based ternary bimetal chalcogenides have very promising potential as multifunctional theragnosis nanoplatform for photothermal treatment of tumors. However, the design and synthesis of such an effective platform remains challenging. In this study, hydrophilic CuCo2S4 nanocrystals (NCs) with a desirable size of ≈10 nm are synthesized by a simple one‐pot hydrothermal route. The as‐prepared ultrasmall CuCo2S4 NCs show: 1) intense near‐infrared absorption, which is attributed to 3d electronic transitions from the valence band to an intermediate band, as identified by density functional theory calculations; 2) high photothermal performance with a photothermal conversion efficiency up to 73.4%; and 3) capability for magnetic resonance (MR) imaging, as a result of the unpaired 3d electrons of cobalt. Finally, it is demonstrated that the CuCo2S4 NCs are a promising “all‐in‐one” photothermal theragnosis nanoplatform for photothermal cancer therapy under the irradiation of a 915 nm laser at a safe power density of 0.5 W cm?2, guided by MR and infrared thermal imaging. This work further promotes the potential applications of ternary bimetal chalcogenides for photothermal theragnosis therapy.  相似文献   

6.
Protein‐based theranostic agents (PBTAs) exhibit superior performance in the diagnosis and therapy of cancers. However, the in vivo applications of PBTA are largely limited by undesired accumulation, penetration, or selectivity. Here, an ATP‐supersensitive protein cluster is fabricated for promoting PBTA delivery and enhancing magnetic resonance imaging (MRI)‐guided tumor photothermal therapy. Gd3+‐ and CuS‐coloaded small bovine serum albumin nanoparticles (GdCuB) are synthesized as the model protein with a size of 9 nm and are encapsulated into charge switchable polycations (DEP) to form DEP/GdCuB nanoclusters of 120 nm. In blood circulation, DEP/GdCuB significantly extends the half‐lifetime and thereby enhances the tumor accumulation of GdCuB. When the clusters reach the tumor site, the extracellular adenosine triphosphate (ATP) can effectively trigger the release of GdCuB, resulting in tumoral deep penetration as well as the activation of T1‐weighted MRI (r1 value switched from 2.8 × 10?3 to 11.8 × 10?3 m ?1 s?1). Furthermore, this delivery strategy also improves the tumoral photothermal therapy efficacy with the MRI‐guided therapy. The study of ATP‐activated nanoclusters develops a novel strategy for tumor deep penetration and on/off imaging of PBTA by size switchable technology, and reveals the potential for MRI‐guided therapy of cancers.  相似文献   

7.
Monitoring of in vivo drug release from nanotheranostics by noninvasive approaches remains very challenging. Herein, novel redox‐responsive polymeric magnetosomes (PolyMags) with tunable magnetic resonance imaging (MRI) properties are reported for in vivo drug release monitoring and effective dual‐modal cancer therapy. The encapsulation of doxorubicin (DOX) significantly decreases PolyMags' T2‐contrast enhancement and transverse relaxation rate R2, depending on the drug loading level. The T2 enhancement and R2 can be recovered once the drug is released upon PolyMags' disassembly. T2‐ and T2*‐MRI and diffusion‐weighted imaging (DWI) are utilized to quantitatively study the correlation between MRI signal changes and drug release, and discover the MR tuning mechanisms. The in vivo drug release pattern is visualized based on such tunable MRI capability via monitoring the changes in T2‐weighted images, T2 and T2* maps, and R2 and R2* values. Interestingly, the PolyMags possess excellent photothermal effect, which can be further enhanced upon DOX loading. The PolyMags are highly efficacious to treat breast tumors on xenograft model with tumor‐targeted photothermal‐ and chemotherapy, achieving a complete cure rate of 66.7%. The concept reported here is generally applicable to other micellar and liposomal systems for image‐guided drug delivery and release applications toward precision cancer therapy.  相似文献   

8.
Facile preparation of multifunctional theranostic nanoplatforms with well‐controlled morphology and sizes remains an attractive in the area of nanomedicine. Here, a new kind of 2D transition metal dichalcogenide, rhenium disulfide (ReS2) nanosheets, with uniform sizes, strong near‐infrared (NIR) light, and strong X‐ray attenuation, is successfully synthesized. After surface modification with poly(ethylene glycol) (PEG), the synthesized ReS2‐PEG nanosheets are stable in various physiological solutions. In addition to their contrasts in photoacoustic imaging and X‐ray computed tomography imaging because of their strong NIR light and X‐ray absorptions, respectively, such ReS2‐PEG nanosheets can also be tracked under nuclear imaging after chelator‐free labeling with radioisotope ions, 99mTc4+. Efficient tumor accumulation of ReS2‐PEG nanosheets is then observed after intravenous injection into tumor‐bearing mice under triple‐modal imaging. The combined in vivo photothermal radiotherapy is further conducted, achieving a remarkable synergistic tumor destruction effect. Finally, no obvious toxicity of ReS2‐PEG nanosheets is observed from the treated mice within 30 d. This work suggests that such ultrathin ReS2 nanosheets with well‐controlled morphology and uniform sizes may be a promising type of multifunctional theranostic agent for remotely triggered cancer combination therapy.  相似文献   

9.
Near‐infrared (NIR)‐absorbing metal‐based nanomaterials have shown tremendous potential for cancer therapy, given their facile and controllable synthesis, efficient photothermal conversion, capability of spatiotemporal‐controlled drug delivery, and intrinsic imaging function. Tantalum (Ta) is among the most biocompatible metals and arouses negligible adverse biological responses in either oxidized or reduced forms, and thus Ta‐derived nanomaterials represent promising candidates for biomedical applications. However, Ta‐based nanomaterials by themselves have not been explored for NIR‐mediated photothermal ablation therapy. In this work, an innovative Ta‐based multifunctional nanoplatform composed of biocompatible tantalum sulfide (TaS2) nanosheets (NSs) is reported for simultaneous NIR hyperthermia, drug delivery, and computed tomography (CT) imaging. The TaS2 NSs exhibit multiple unique features including (i) efficient NIR light‐to‐heat conversion with a high photothermal conversion efficiency of 39%, (ii) high drug loading (177% by weight), (iii) controlled drug release triggered by NIR light and moderate acidic pH, (iv) high tumor accumulation via heat‐enhanced tumor vascular permeability, (v) complete tumor ablation and negligible side effects, and (vi) comparable CT imaging contrast efficiency to the widely clinically used agent iobitridol. It is expected that this multifunctional NS platform can serve as a promising candidate for imaging‐guided cancer therapy and selection of cancer patients with high tumor accumulation.  相似文献   

10.
Transition metal‐based nanoparticles have shown their broad applications in versatile biomedical applications. Although traditional iron‐based nanoparticles have been extensively explored in biomedicine, transition metal manganese (Mn)‐based nanoparticulate systems have emerged as a multifunctional nanoplatform with their intrinsic physiochemical property and biological effect for satisfying the strict biomedical requirements. This comprehensive review focuses on recent progress of Mn‐based functional nanoplatforms in biomedicine with the particular discussion on their elaborate construction, physiochemical property, and theranostic applicability. Several Mn‐based nanosystems are discussed in detail, including solid/hollow MnOx nanoparticles, 2D MnOx nanosheets, MnOx‐silica/mesoporous silica nanoparticles, MnOx‐Fe3O4 nanoparticles, MnOx‐Au, MnOx‐fluorescent nanoparticles, Mn‐based organic composite nanosystem, and some specific/unique Mn‐based nanocomposites. Their versatile biomedical applications include pH/reducing‐responsive T1‐weighted positive magnetic resonance imaging, controlled drug loading/delivery/release, protection of neurological disorder, photothermal hyperthermia, photodynamic therapy, chemodynamic therapy, alleviation of tumor hypoxia, immunotherapy, and some specific synergistic therapies, which are based on their disintegration behavior under the mildly acidic/reducing condition, multiple enzyme‐mimicking activity, catalytic‐triggering Fenton reaction, etc. The biological effects and biocompatibility of these Mn‐based nanosystems are also discussed, accompanied with a discussion on challenges/critical issues and an outlook on the future developments and clinical‐translation potentials of these intriguing Mn‐based functional nanoplatforms.  相似文献   

11.
The booming development of nanomedicine offers great opportunities for cancer diagnostics and therapeutics. Herein, a magnetic targeting‐enhanced cancer theranostic strategy using a multifunctional magnetic‐plasmonic nano‐agent is developed, and a highly effective in vivo tumor photothermal therapy, which is carefully planed based on magnetic resonance (MR)/photoacoustic (PA) multimodal imaging, is realized. By applying an external magnetic field (MF) focused on the targeted tumor, a magnetic targeting mediated enhanced permeability and retention (MT‐EPR) effect is observed. While MR scanning provides tumor localization and reveals time‐dependent tumor homing of nanoparticles for therapeutic planning, photoacoustic imaging with higher spatial resolution allows noninvasive fine tumor margin delineation and vivid visualization of three dimensional distributions of theranostic nanoparticles inside the tumor. Utilizing the near‐infrared (NIR) plasmonic absorbance of those nanoparticles, selective photothermal tumor ablation, whose efficacy is predicted by real‐time infrared thermal imaging intra‐therapeutically, is carried out and then monitored by MR imaging for post‐treatment prognosis. Overall, this study illustrates the concept of imaging‐guided MF‐targeted photothermal therapy based on a multifunctional nano‐agent, aiming at optimizing therapeutic planning to achieve the most efficient cancer therapy.  相似文献   

12.
Realizing precise control of the therapeutic process is crucial for maximizing efficacy and minimizing side effects, especially for strategies involving gene therapy (GT). Herein, a multifunctional Prussian blue (PB) nanotheranostic platform is first designed and then loaded with therapeutic plasmid DNA (HSP70‐p53‐GFP) for near‐infrared (NIR) light‐triggered thermo‐controlled synergistic GT/photothermal therapy (PTT). Due to the unique structure of the PB nanocubes, the resulting PB@PEI/HSP70‐p53‐GFP nanoparticles (NPs) exhibit excellent photothermal properties and pronounced tumor‐contrast performance in T1/T2‐weighted magnetic resonance imaging. Both in vitro and in vivo studies demonstrate that mild NIR‐laser irradiation (≈41 °C) activates the HSP70 promoter for tumor suppressor p53‐dependent apoptosis, while strong NIR‐laser irradiation (≈50 °C) induces photothermal ablation for cellular dysregulation and necrosis. Significant synergistic efficacy can be achieved by adjusting the NIR‐laser irradiation (from ≈41 to ≈50 °C), compared to using GT or PTT alone. In addition, in vitro and in vivo toxicity studies demonstrate that PB@PEI/HSP70‐p53‐GFP NPs have good biocompatibility. Therefore, this work provides a promising theranostic approach for controlling combined GT and PTT via the heat‐shock response.  相似文献   

13.
Synergistic therapy is an accepted method of enhancing the efficacy of cancer therapies. In this study, cypate‐conjugated porous NaLuF4 doped with Yb3+, Er3+, and Gd3+ is synthesized and its potential for upconversion luminescence/magnetic resonance dual‐modality molecular imaging for guiding oncotherapy is tested. Loading cypate‐conjugated upconversion nanoparticles (UCNP‐cy) with small interfering RNA gene against heat shock protein 70 (UCNP‐cy‐siRNA) enhances the cell damage. UCNP‐cy‐siRNA exhibits remarkable antitumor efficacy in vivo as a result of the synergistic effects of gene silencing and photothermal therapy, with low drug dose and minimal side effects. This result thus provides an explicit strategy for developing next‐generation multifunctional nanoplatforms for multimodal imaging‐guided synergistic oncotherapy.  相似文献   

14.
The quantitative detection of microRNA (miR) and multimode‐imaging‐induced photothermal therapy in vivo have become the focus of much attention. Platinum (Pt) decorated gold nanorods (AuNR‐Pt) and Ag2S core–satellite (AuNR‐Pt@Ag2S) multifunctional nanostructures are fabricated to quantify intracellular miRs (miR‐21), near‐infrared fluorescence cell quantitative imaging, and tumor ablation in vivo. When combined with miR‐21, the nanoassembly displays significant fluorescence intensity in the second window of the near‐infrared region (1000–1700 nm) after 808 nm excitation. The Ag2S fluorescence intensity has a good linear relationship with the amount of intracellular miR in the range of 0.054–20.45 amol ngRNA ?1 and a limit of detection of 0.0082 amol ngRNA ?1. The nanoassembly is also used to develop multimodal bioimaging, including near‐infrared, X‐ray computed tomographic, and photoacoustic imaging in HeLa‐tumor‐bearing mice. Moreover, the tumors are completely eliminated by the high photothermal capacity of the AuNR‐Pt@Ag2S assembly. This nanoassembly provides a multifunctional nanoplatform for the ultrasensitive detection of miRs and tumor diagnosis and therapy in vivo.  相似文献   

15.
The encapsulation of nitroxide radicals within ultrashort (ca. 50 nm) single‐walled carbon nanotubes (US‐tubes) is achieved. Tempo‐ and Iodo‐Tempo@US‐tubes are characterized by thermogravimetric analysis (TGA), X‐ray photoelectron spectroscopy (XPS), and Raman spectroscopy. Electron paramagnetic resonance (EPR) spectra display characteristic signals due to the detection of the spin probes within the US‐tubes. Longitudinal proton relaxivities (r1) of both nitroxide@US‐tubes samples are 7 to 13 times greater than the free nitroxide radicals in solution, giving relaxivities comparable to the clinical contrast agent (CA) Magnevist. In addition, transverse proton relaxivities (r2) show unprecedented proton relaxation enhancement in comparison to any other reported nitroxide radical‐based system or the clinically approved T2 CA, Resovist, under the same conditions. T2‐weighted magnetic resonance imaging (MRI) phantom images show that the encapsulation of nitroxide radicals within the US‐tubes produces good contrast enhancement due to their high r2 relaxivities. The nitroxide radicals@US‐tube agents are a new promising class of spin probes for MRI and electronic paramagnetic resonance imaging (EPRI) labeling, tracking, and diagnosis.  相似文献   

16.
Integrating multiple functionalities into individual nanoscale complexes is of tremendous importance in biomedicine, expanding the capabilities of nanoscale structures to perform multiple parallel tasks. Here, the ability to enhance two different imaging technologies simultaneously—fluorescence optical imaging and magnetic resonance imaging—with antibody targeting and photothermal therapeutic actuation is combined all within the same nanoshell‐based complex. The nanocomplexes are constructed by coating a gold nanoshell with a silica epilayer doped with Fe3O4 and the fluorophore ICG, which results in a high T2 relaxivity (390 mM ?1 s?1) and 45× fluorescence enhancement of ICG. Bioconjugate nanocomplexes target HER2+ cells and induce photothermal cell death upon near‐IR illumination.  相似文献   

17.
Fabrication of ultrasmall single‐component omnipotent nanotheranostic agents integrated with multimodal imaging and multiple therapeutic functions becomes more and more practically relevant but challenging. In this article, sub 10 nm Bi2S3 biocompatible particles are prepared through a bovine serum albumin (BSA)‐mediated biomineralization process under ambient aqueous conditions. Owing to the ultrasmall size and colloidal stability, the resulting nanoparticles (NPs) present outstanding blood circulation behavior and excellent tumor targeting ability. Toward theranostic applications, the biosafety profile is carefully investigated. In addition, photothermal conversion is characterized for both photoacoustic imaging and photothermal treatment of cancers. Upon radiolabeling, the performance of the resulting particles for SPECT/CT imaging in vivo is also carried out. Additionally, different combinations of treatments are applied for evaluating the performance of the as‐prepared Bi2S3 NPs in photothermal‐ and radiotherapy of tumors. Due to the remarkable photothermal conversion efficiency and large X‐ray attenuation coefficient, the implanted tumors are completely eradicated through combined therapies, which highlights the potential of BSA‐capped Bi2S3 NPs as a novel multifunctional nanotheranostic agent.  相似文献   

18.
Given the promise of carbon nanotubes (CNTs) for photothermal therapy, drug delivery, tissue engineering, and gene therapy, there is a need for non‐invasive imaging methods to monitor CNT distribution and fate in the body. In this study, non‐ionizing whole‐body high field magnetic resonance imaging (MRI) is used to follow the distribution of water‐dispersible non‐toxic functionalized CNTs administrated intravenously to mice. Oxidized CNTs are endowed with positive MRI contrast properties by covalent functionalization with the chelating ligand diethylenetriaminepentaacetic dianhydride (DTPA), followed by chelation to Gd3+. The structural and magnetic properties, MR relaxivities, cellular uptake, and application for MRI cell imaging of Gd‐CNTs in comparison to the precursor oxidized CNTs are evaluated. Despite the intrinsic T2 contrast of oxidized CNTs internalized in macrophages, the anchoring of paramagnetic gadolinium onto the nanotube sidewall allows efficient T1 contrast and MR signal enhancement, which is preserved after CNT internalization by cells. Hence, due to their high dispersibility, Gd‐CNTs have the potential to produce positive contrast in vivo following injection into the bloodstream. The uptake of Gd‐CNTs in the liver and spleen is assessed using MRI, while rapid renal clearance of extracellular Gd‐CNTs is observed, confirming the evidences of other studies using different imaging modalities.  相似文献   

19.
Here, in terms of the highly reactive oxidative hydroxyl radical (?OH) generation ability of isoniazid (INH) catalyzed by Mn2+ ion and the photothermal effect of WSSe nanoflakes, a WSSe/MnO2‐INH nanocomposite for synergistic anticancer treatment is developed. Advanced INH‐induced ?OH formation ability is systemically demonstrated in the presence of manganese and relevant non‐Fenton‐type mechanism, and good photothermal conversion efficiency of the WSSe/MnO2 nanocomposite. After modifying with mitochondria‐targeted triphenylphosphonium bromide (TPP) moieties and camouflaging with cancer cells membrane (WSSe/MnO2‐INH‐TPP@CM), it confers a sequential cell‐to‐mitochondria targeting ability. In vivo X‐ray computed tomography and magnetic resonance tumor imaging capability of the nanocomposite are also revealed. The mitochondria‐targeted oxidative damage and photothermal therapy by WSSe/MnO2‐INH‐TPP@CM results in excellent anticancer treatment efficacy both in vitro and in vivo. This is the first exploration of the possibility of non‐Fenton‐type ?OH formation for anticancer treatment, which opens new opportunities for ROS‐based and combined cancer treatment strategies.  相似文献   

20.
Multifunctional theranostic agents have become rather attractive to realize image‐guided combination cancer therapy. Herein, a novel method is developed to synthesize Bi2Se3 nanosheets decorated with mono‐dispersed FeSe2 nanoparticles (FeSe2/Bi2Se3) for tetra‐modal image‐guided combined photothermal and radiation tumor therapy. Interestingly, upon addition of Bi(NO3)3, pre‐made FeSe2 nanoparticles via cation exchange would be gradually converted into Bi2Se3 nanosheets, on which remaining FeSe2 nanoparticles are decorated. The yielded FeSe2/Bi2Se3 composite‐nanostructures are then modified with polyethylene glycol (PEG). Taking advantages of the high r 2 relaxivity of FeSe2, the X‐ray attenuation ability of Bi2Se3, the strong near‐infrared optical absorbance of the whole nanostructure, as well as the chelate‐free radiolabeling of 64Cu on FeSe2/Bi2Se3‐PEG, in vivo magnetic resonance/computer tomography/photoacoustic/position emission tomography multimodal imaging is carried out, revealing efficient tumor homing of FeSe2/Bi2Se3‐PEG after intravenous injection. Utilizing the intrinsic physical properties of FeSe2/Bi2Se3‐PEG, in vivo photothermal and radiation therapy to achieve synergistic tumor destruction is then realized, without causing obvious toxicity to the treated animals. This work presents a unique method to synthesize composite‐nanostructures with highly integrated functionalities, promising not only for nano‐biomedicine but also potentially for other different nanotechnology fields.  相似文献   

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