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- 2017
- spectral reconstruction
- interference
- polarization
- transform
- imaging spectrometer
- Optoelectronic Information Science and Engineering
- BITTT
- Zhejiang University
- Guilin University of Aerospace Technology
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Self-Luminescing Theranostic Nanoreactors with Intraparticle Relayed Energy Transfer for Tumor Microenvironment Activated Imaging and Photodynamic Therapy
摘要： The low tissue penetration depth of external excitation light severely hinders the sensitivity of fluorescence imaging (FL) and the efficacy of photodynamic therapy (PDT) in vivo; thus, rational theranostic platforms that overcome the light penetration depth limit are urgently needed. To overcome this crucial problem, we designed a self-luminescing nanosystem (denoted POCL) with near-infrared (NIR) light emission and singlet oxygen (1O2) generation abilities utilizing an intraparticle relayed resonance energy transfer strategy. Methods: Bis[3,4,6-trichloro-2-(pentyloxycarbonyl) phenyl] oxalate (CPPO) as a chemical energy source with high reactivity toward H2O2, poly[(9,9’-dioctyl-2,7-divinylene-?uorenylene)-alt-2-methoxy-5-(2-ethyl-hexyloxy)-1,4-phenylene] (PFPV) as a highly efficient chemiluminescence converter, and tetraphenylporphyrin (TPP) as a photosensitizer with NIR emission and 1O2 generation abilities were coencapsulated by self-assembly with poly(ethyleneglycol)-co-poly(caprolactone) (PEG-PCL) and folate-PEG-cholesterol to form the POCL nanoreactor, with folate as the targeting group. A series of in vitro and in vivo analyses, including physical and chemical characterizations, tumor targeting ability, tumor microenvironment activated imaging and photodynamic therapy, as well as biosafety, were systematically investigated to characterize the POCL. Results: The POCL displayed excellent NIR luminescence and 1O2 generation abilities in response to H2O2. Therefore, it could serve as a speci?c H2O2 probe to identify tumors through chemiluminescence imaging and as a chemiluminescence-driven PDT agent for inducing tumor cell apoptosis to inhibit tumor growth due to the abnormal overproduction of H2O2 in the tumor microenvironment. Moreover, the folate ligand on the POCL surface can further improve the accumulation at the tumor site via a receptor-mediated mechanism, thus enhancing tumor imaging and the therapeutic effects both in vitro and in vivo but without any observable systemic toxicity. Conclusion: The nanosystem reported here might serve as a targeted, smart, precise, and noninvasive strategy triggered by the tumor microenvironment rather than by an outside light source for cancer NIR imaging and PDT treatment without limitations on penetration depth.
关键词： chemiluminescent imaging,H2O2,self-luminescing theranostic nanoreactors,intraparticle relayed energy transfer,PDT
更新于2025-09-23 15:23:52
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Positron emission tomography/computed tomography outperforms MRI in the diagnosis of local recurrence and residue of nasopharyngeal carcinoma: An update evidence from 44 studies
摘要： Studies on nasopharyngeal carcinoma (NPC) in five electronic databases were systematically searched online from the inception to June 5, 2018. Quality of the included studies was assessed using the updated Quality Assessment of Diagnostic Accuracy Studies 2. Data of sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, diagnostic odds ratio, and the 95% confidence intervals were pooled using a bivariate random‐effect model. Forty‐four studies with 61 groups of data and totally 3369 patients were included in the qualitative and quantitative synthesis analysis. The overall estimated sensitivity and specificity of positron emission tomography/computed tomography/magnetic resonance imaging (PET‐CT/MRI) for local recurrent/residual NPC were 0.90 and 0.85, respectively. The pooled area under the curve of (AUC) of PET‐CT/MRI in the summary receiver operator characteristic curve was 0.94. Subgroup analysis showed MRI vs PET‐CT had lower sensitivity (0.83 vs 0.92) and specificity (0.78 vs 0.89). The AUCs of MRI and PET‐CT were 0.87 and 0.96, respectively. No‐cross of 95% CI was found in MRI vs PET/CT (0.87‐0.90 vs 0.94‐0.98). Meta‐regression showed PET/CT vs MRI was a potential source of heterogeneity. PET/CT and MRI both showed quite high overall ability in diagnosing local recurrent/residual NPC, but the subgroup analysis indicated PET‐CT was superior over MRI in diagnosis of local recurrence and residue of NPC after radiotherapy. The examination methods affected the heterogeneity within studies.
关键词： specificity,positron emission tomography/computed tomography,sensitivity,magnetic resonance imaging,recurrence/residue,nasopharyngeal carcinoma
更新于2025-09-23 15:23:52
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Plasmonic Gold Nanovesicles for Biomedical Applications
摘要： Gold nanoparticles (GNPs), with tunable optical properties, bioinertness, and surface multivalent effect, have been widely explored for biomedical applications. As one classical type of GNPs-based assemblies, plasmonic gold nanovesicles (GVs), with a hollow cavity, “solid skeleton” composed of GNPs cores and a “soft body” composed of functional polymers, have attracted considerable attention due to their tunable localized surface plasmon resonance, strong surface-enhanced Raman scattering properties, and high photothermal conversion efficiency. This review summarizes recent advances in biomedical applications for plasmonic GVs. Firstly, the synthesis methods of GVs are mainly including self-assembly and in situ gold growth methods. Secondly, the classification of GVs is described according to the morphology of GNPs cores. Thirdly, different biomedical applications of GVs are elaborated, including in vitro diagnosis, in vivo imaging, and in vivo therapy. Finally, the challenges and perspectives of GVs are discussed.
关键词： cancer therapy,drug delivery,gold nanovesicles,biodetection,cancer imaging
更新于2025-09-23 15:23:52
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Influence of Heart Rate and Innovative Motion-Correction Algorithm on Coronary Artery Image Quality and Measurement Accuracy Using 256-Detector Row Computed Tomography Scanner: Phantom Study
摘要： Objective: To investigate the efficacy of motion-correction algorithm (MCA) in improving coronary artery image quality and measurement accuracy using an anthropomorphic dynamic heart phantom and 256-detector row computed tomography (CT) scanner. Materials and Methods: An anthropomorphic dynamic heart phantom was scanned under a static condition and under heart rate (HR) simulation of 50–120 beats per minute (bpm), and the obtained images were reconstructed using conventional algorithm (CA) and MCA. We compared the subjective image quality of coronary arteries using a four-point scale (1, excellent; 2, good; 3, fair; 4, poor) and measurement accuracy using measurement errors of the minimal luminal diameter (MLD) and minimal luminal area (MLA). Results: Compared with CA, MCA significantly improved the subjective image quality at HRs of 110 bpm (1.3 ± 0.3 vs. 1.9 ± 0.8, p = 0.003) and 120 bpm (1.7 ± 0.7 vs. 2.3 ± 0.6, p = 0.006). The measurement error of MLD significantly decreased on using MCA at 110 bpm (11.7 ± 5.9% vs. 18.4 ± 9.4%, p = 0.013) and 120 bpm (10.0 ± 7.3% vs. 25.0 ± 16.5%, p = 0.013). The measurement error of the MLA was also reduced using MCA at 110 bpm (19.2 ± 28.1% vs. 26.4 ± 21.6%, p = 0.028) and 120 bpm (17.9 ± 17.7% vs. 34.8 ± 19.6%, p = 0.018). Conclusion: Motion-correction algorithm can improve the coronary artery image quality and measurement accuracy at a high HR using an anthropomorphic dynamic heart phantom and 256-detector row CT scanner.
关键词： Heart rate,Tomography,X-ray computed,Coronary vessels,Phantoms,Imaging,Motion-correction algorithm
更新于2025-09-23 15:23:52
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Identifying Mangrove Species Using Field Close-Range Snapshot Hyperspectral Imaging and Machine-Learning Techniques
摘要： Investigating mangrove species composition is a basic and important topic in wetland management and conservation. This study aims to explore the potential of close-range hyperspectral imaging with a snapshot hyperspectral sensor for identifying mangrove species under field conditions. Specifically, we assessed the data pre-processing and transformation, waveband selection and machine-learning techniques to develop an optimal classification scheme for eight mangrove species in Qi’ao Island of Zhuhai, Guangdong, China. After data pre-processing and transformation, five spectral datasets, which included the reflectance spectra R and its first-order derivative d(R), the logarithm of the reflectance spectra log(R) and its first-order derivative d[log(R)], and hyperspectral vegetation indices (VIs), were used as the input data for each classifier. Consequently, three waveband selection methods, including the stepwise discriminant analysis (SDA), correlation-based feature selection (CFS), and successive projections algorithm (SPA) were used to reduce dimensionality and select the effective wavebands for identifying mangrove species. Furthermore, we evaluated the performance of mangrove species classification using four classifiers, including linear discriminant analysis (LDA), k-nearest neighbor (KNN), random forest (RF), and support vector machine (SVM). Application of the four considered classifiers on the reflectance spectra of all wavebands yielded overall classification accuracies of the eight mangrove species higher than 80%, with SVM having the highest accuracy of 93.54% (Kappa = 0.9256). Using the selected wavebands derived from SPA, the accuracy of SVM reached 93.13% (Kappa = 0.9208). The addition of hyperspectral VIs and d[log(R)] spectral datasets further improves the accuracies to 93.54% (Kappa = 0.9253) and 96.46% (Kappa = 0.9591), respectively. These results suggest that it is highly effective to apply field close-range snapshot hyperspectral images and machine-learning classifiers to classify mangrove species.
关键词： machine learning,waveband selection,mangrove species classification,close-range hyperspectral imaging,field hyperspectral measurement
更新于2025-09-23 15:23:52
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A Nanoprobe for Diagnosing and Mapping Lymphatic Metastasis of Tumor Using 3D Multispectral Optoacoustic Tomography Owing to Aggregation/Deaggregation Induced Spectral Change
摘要： Lymphatic metastasis of tumor is one of leading causes of cancer-related death, and diagnosing lymphatic metastasis is of significance in terms of optimal disease management and possible better outcomes for patients. Herein a turn-on optoacoustic nanoprobe is reported for noninvasively diagnosing and locating lymphatic metastasis in vivo. A positively charged tricyanofuran-containing polyene chromophore (TCHM) with high extinction coefficient is designed, synthesized, and allowed to form the nanoprobe with a negatively charged hyaluronan. The TCHMs take an aggregated state within the nanoprobe and exhibit weak absorption at 882 nm, the overexpressed hyaluronidase in cancer cells specifically degrades hyaluronan into small fragments and disaggregates TCHMs, thereby greatly enhancing the absorption at 882 nm and generating prominent optoacoustic signals. For multispectral optoacoustic tomography (MSOT) imaging in vivo, mice models with subcutaneous tumor and orthotopic bladder tumor are imaged first to demonstrate the nanoprobe’s capability for detecting HAase-overexpressing tumors. A mouse model of lymphatic metastasis of tumor is then established and the lymphatic metastasis is successfully imaged and tracked optoacoustically. The imaging results were verified using multiple biochemical assays. Moreover, 3D MSOT renderings are obtained for precisely locating and tracking the metastasis of tumor in lymphatic system in a spatiotemporal manner.
关键词： lymphatic metastasis,imaging,multispectral,nanoprobe,3D,optoacoustic tomography,aggregation
更新于2025-09-23 15:23:52
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Dendrimeric nanoparticles for two-photon photodynamic therapy and imaging: synthesis, photophysical properties and cytotoxicity under two-photon irradiation in the NIR
摘要： The synthesis and the photophysical properties of a new class of fully organic monodisperse nanoparticles for combined two-photon imaging and photodynamic therapy are described. The design of such nanoparticle is based on the covalent immobilization of a dedicated quadrupolar dye - which combine large two-photon absorbing (2PA) properties, fluorescence and singlet oxygen generation ability - in a phosphorous-based dendrimeric architecture. Firstly, a bifunctional quadrupolar dye bearing two different grafting moieties, a phenol function and an aldehyde function, was synthesized. It was then covalently grafted through its phenol function to a phosphorus-based dendrimer scaffold of generation 1. The remaining aldehyde functions were then used to carry on the dendrimer synthesis up to generation 2 introducing finally at its periphery 24 water-solubilizing triethyleneglycol chains. A dendrimer confining 12 photoactive quadrupolar units in its inner scaffold and showing water solubility was thus obtained. Interestingly, the G1 and G2 dendrimers retain some fluorescence as well as significant singlet oxygen production efficiencies while they were found to show very high 2PA cross-sections in a broad range of the NIR biological spectral window. Hydrophilic dendrimer G2 was tested in vitro on breast cancer cells, first in one- and two-photon microscopy, which allowed for visualization of their cell internalization, then in two-photon photodynamic therapy. While being non-toxic in the dark and, more importantly, under daylight exposition, dendrimer G2 proved to be very efficient cell death inducer only under two-photon irradiation in the NIR.
关键词： photophysics,photodynamic therapy,dendrimers,imaging,fluorescence
更新于2025-09-23 15:23:52
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Surface-enhanced Raman scattering (SERS) imaging of bioactive metabolites in mixed bacterial populations
摘要： Bacteria frequently live in mixed multispecies communities, shaped by the action of bioactive metabolites that are secreted by the residing microbial species. The identification and tracking of such chemical exchange processes is fundamental toward understanding how these particular extracellular molecules modulate microbial communities and functions. In this context, most chemical imaging approaches so far have focused on the analysis of metabolic interactions occurring between microbial populations co-cultured separately. We demonstrate here the application of surface-enhanced Raman scattering (SERS) spectroscopy as a valuable imaging tool for the non-invasive detection and visualization of metabolites secreted by Escherichia coli and Pseudomonas aeruginosa bacteria, cultured as mixed populations and thereby mimicking the complexity of natural microbial communities. SERS enabled the simultaneous detection and in situ visualization of indole and pyocyanin, revealing the down-regulation of pyocyanin expression due to indole signaling. The successful detection of chemical interactions in mixed bacterial populations shows the potential of SERS for the investigation of the chemistry underpinning multispecies microbial communities.
关键词： Quorum sensing,Plasmonics,Indole,SERS imaging,Pyocyanin
更新于2025-09-23 15:23:52
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On-demand CO release for amplification of chemotherapy by MOF functionalized magnetic carbon nanoparticles with NIR irradiation
摘要： Carbon monoxide (CO) gas therapy combined with chemotherapy and photothermal therapy (PTT) is a promising treatment mode for malignant tumor. Herein, we firstly reported doxorubicin (DOX) loaded Mn carbonyl modified Fe (III)-based nanoMOFs (MIL-100) coated PEGylated magnetic carbon nanoparticles (denoted as MCM@PEG-CO-DOX NPs) as theranostics nanoplatforms for near-infrared (NIR)-responded CO-DOX combination therapy. MIL-100 as a good nanocarrier of DOX with high loading capacity can also chelate the Mn carbonyl after a smart modification. Meanwhile, magnetic carbon core possessed photothermal effect, which can convert the NIR light to heat by an 808 nm laser irradiation, resulting in the on-demand release of CO and DOX. As a result, combining with PTT, MCM@PEG-CO-DOX NPs killed tumor efficiently. Moreover, our synthesized MCM@PEG-CO-DOX NPs were capable of realizing tumor dual-mode imaging including magnetic resonance imaging (MRI) and photoacoustic imaging (PAI).
关键词： synergistic treatment,dual-mode imaging,MOFs,CO gas therapy,carbon nanoparticles
更新于2025-09-23 15:23:52
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A deep learning based feature extraction method on hyperspectral images for nondestructive prediction of TVB-N content in Pacific white shrimp (Litopenaeus vannamei)
摘要： Hyperspectral imaging (HSI) technique with spectral range of 900e1700 nm was implemented to predict total volatile basic nitrogen (TVB-N) content in Pacific white shrimp. Successive projections algorithm (SPA) and deep-learning-based stacked auto-encoders (SAEs) algorithm were comparatively used for spectral feature extraction. Least-squares support vector machine (LS-SVM), partial least squares regression (PLSR) and multiple linear regression (MLR) were used for prediction. The results demonstrated that the SAEs-based prediction models (SAEs-LS-SVM, SAEs-MLR and SAEs-PLSR) performed better than either full wavelengths-based or SPA-based prediction models. The SAEs-LS-SVM was considered to be the best model with RP2 value of 0.921, RMSEP value of 6.22 mg N [100 g]?1, RPD value of 3.58 and computational time of 3.9 ms for predicting TVB-N in prediction set. The results of this study indicated that SAEs has a high potential in the multivariate analysis of hyperspectral images for shrimp quality inspections.
关键词： Stacked auto-encoders,Pacific white shrimp,Total volatile basic nitrogen,Nondestructive prediction,Hyperspectral imaging
更新于2025-09-23 15:23:52