Liver cancer, specifically hepatocellular carcinoma (HCC), is a malignant neoplasm of the digestive system, characterized by exceptionally high morbidity and mortality rates on a global scale. Early detection and diag...Liver cancer, specifically hepatocellular carcinoma (HCC), is a malignant neoplasm of the digestive system, characterized by exceptionally high morbidity and mortality rates on a global scale. Early detection and diagnosis are critical measures for enhancing the prognosis of patients diagnosed with HCC. An improved prognosis is significantly reliant on the timely diagnosis of the disease and effective therapeutic monitoring. Activatable fluorescent probes are essential for detecting and imaging biomarkers related to disease diagnosis and in vivo imaging. This paper reviews the fluorescent probes developed over the past five years for the detection and imaging of HCC. This noninvasive optical imaging modality demonstrates significant promise in targeting pathological sites and is anticipated to facilitate potential clinical translation.展开更多
Photodynamic therapy(PDT)is a new and rapidly developing treatment modality for dinical cancer therapy.Semiconductor polymer dots(Pdots)doped with photosensitizers have been successfully applied to PDT,and have made p...Photodynamic therapy(PDT)is a new and rapidly developing treatment modality for dinical cancer therapy.Semiconductor polymer dots(Pdots)doped with photosensitizers have been successfully applied to PDT,and have made progress in the field of tumor therapy.However,the problems of severe photosensitivity and limited tisue penetration depth are needed to be solved during the implementation process of PDT.Here we developed the Pdots doped with photosensitizer molecule Chlorin e6(Ce6)and photochromic molecule 1,2-bis(2,4-dimethy1-5 phenyl-3-thiophene)-3,3,4,5-hexafuoro-1-cyclopentene(BTE)to construct a photoswitchable nanoplatform for PDT.The Ce6-BTE-doped Pdots were in the green region,and the tissue penetration depth was increased compared with most Pdots in the blue region.The reversible conversion of BTE under different light irradiation was utilized to regulate the photodynamic effect and solve the problem of photosensitivity.The prepared Ce6-BTE-doped Pdots had small size,excellent optical property,efficient ROS generation and good photoswitchable ability.The cellular uptake,cytotoxicity,and photodynamic effect of the Pdots were detected in human colon tumor cells.The experiments in vitro indicated that Ce6-BTE-doped Pdots could exert excellent photodynamic effect in ON state and reduce photosensitivity in OFF state.These results demonstrated that this nanoplatform holds the potential to be used in clinical PDT.展开更多
The space charge accumulation in the heterogeneous insulation composed of cross-linked polyethylene(XLPE)cable and silicone rubber(SiR)accessory poses a serious threat to the safe operation of the high voltage direct ...The space charge accumulation in the heterogeneous insulation composed of cross-linked polyethylene(XLPE)cable and silicone rubber(SiR)accessory poses a serious threat to the safe operation of the high voltage direct current(HVDC)cable.When the cable is in heavy load,the charge transport behaviour in XLPE/SiR becomes more complicated due to the high temperature.In order to investigate the charge transport characteristics of XLPE/SiR under heavy load condition,the simultaneous measurement of space charge and relaxation current is performed on XLPE/SiR at both 70℃ and 30℃ with different polarities.The results show that the polarity of the interface charges in XLPE/SiR is always consistent with that of the SiR side electrode,and the influence of high temper-ature(70℃)caused by heavy load on the interface charge accumulation of XLPE/SiR is reversed at different polarities.The interface trap depth of XLPE/SiR is consistently greater than the bulk trap depths in both XLPE and SiR.When at high temperature of 70℃,the depth and density of interface traps increase,and the bulk traps in XLPE and SiR also exhibit increased depth.The component of polarisation relaxation current associated with space charge activity increases and exhibits longer decay time at 70℃,indicating more active and complex charge trapping-detrapping activities under heavy load condition.In this paper,an advanced simultaneous measurement is used to correlate the internal charge distribution with the external current for analysis,and the charge transport characteristics of XLPE/SiR under heavy load condition is revealed.The results can provide reference for the operation and maintenance of HVDC cable,and can also provide a basis for the space charge regulation of heterogeneous insulation at HVDC cable accessories.展开更多
Deterministic encryption(DET)allows for fast retrieval of encrypted information,but it would cause significant leakage of frequency information of the underlying data,which results in an array of inference attacks.Sim...Deterministic encryption(DET)allows for fast retrieval of encrypted information,but it would cause significant leakage of frequency information of the underlying data,which results in an array of inference attacks.Simply replacing DET with fully randomized encryption is often undesirable in the scenario of an encrypted database since it incurs a large overhead in query and storage.Frequency Smoothing Encryption(FSE)is a practical encryption scheme to protect frequency information.Current FSE constructions still fall short of efficiency and a reasonable security definition.We revisit FSE and propose two security definitions from both theoretical and practical perspectives.Furthermore,we adopt a novel partitioning strategy to construct a new FSE scheme to improve performance.Experimental results show that compared with others,our scheme achieves excellent query performance while attaining security against inference attacks.展开更多
As a hybrid imaging technique, photoacoustic imaging （PAI） can provide multiscale morphological information of tissues, and the use of multi-spectral PAI （MSPAI） can recover the spatial distribution of chromophore...As a hybrid imaging technique, photoacoustic imaging （PAI） can provide multiscale morphological information of tissues, and the use of multi-spectral PAI （MSPAI） can recover the spatial distribution of chromophores of interest, such as hemoglobin within tissues. Herein, we developed a contrast agent that can very effectively combine multiscale PAI with MSPAI for a more comprehensive characterization of complex biological tissues. Specifically, we developed novel PIID-DTBT based semi-conducting polymer dots （Pdots） that show broad and strong optical absorption in the visible-light region （500-700 nm）. The performances of gold nanoparticles （GNPs） and gold nanorods （GNRs）, which have been verified as excellent photoacoustic contrast agents, were compared with that of the Pdots based on the multiscale PAI system. Both ex vivo and in vivo experiments demonstrated that the Pdots have better photoacoustic conversion efficiency at 532 nm than GNPs and showed similar photoacoustic performance with GNRs at 700 nm at the same mass concentration. Photostability and toxicity tests demonstrated that the Pdots are photostable and biocompatible. More importantly, an in vivo MSPAI experiment indicated that the Pdots have better photoacoustic performance than the blood and therefore the signals can be accurately extracted from the background of vascular-rich tissues. Our work demonstrates the great potential of Pdots as highly effective contrast agents for the precise localization of lesions relative to the blood vessels based on multiscale PAI and MSPAI.展开更多
基金supported by the National Natural Science Foundation of China (Grant Nos. 82202296, 82302277, and 32271520)Natural Science Foundation of Hunan Province (Grant Nos. 2022JJ30756, 2023JJ40087, and 2022RC1232)the Scientific Research Fund of Hunan Provincial Education Department (Grant No. 22B0896).
文摘Liver cancer, specifically hepatocellular carcinoma (HCC), is a malignant neoplasm of the digestive system, characterized by exceptionally high morbidity and mortality rates on a global scale. Early detection and diagnosis are critical measures for enhancing the prognosis of patients diagnosed with HCC. An improved prognosis is significantly reliant on the timely diagnosis of the disease and effective therapeutic monitoring. Activatable fluorescent probes are essential for detecting and imaging biomarkers related to disease diagnosis and in vivo imaging. This paper reviews the fluorescent probes developed over the past five years for the detection and imaging of HCC. This noninvasive optical imaging modality demonstrates significant promise in targeting pathological sites and is anticipated to facilitate potential clinical translation.
基金supported by the science and technology research project of education department of Jilin province(JJKH20211189KJ)Jilin province medical and health talents special project.
文摘Photodynamic therapy(PDT)is a new and rapidly developing treatment modality for dinical cancer therapy.Semiconductor polymer dots(Pdots)doped with photosensitizers have been successfully applied to PDT,and have made progress in the field of tumor therapy.However,the problems of severe photosensitivity and limited tisue penetration depth are needed to be solved during the implementation process of PDT.Here we developed the Pdots doped with photosensitizer molecule Chlorin e6(Ce6)and photochromic molecule 1,2-bis(2,4-dimethy1-5 phenyl-3-thiophene)-3,3,4,5-hexafuoro-1-cyclopentene(BTE)to construct a photoswitchable nanoplatform for PDT.The Ce6-BTE-doped Pdots were in the green region,and the tissue penetration depth was increased compared with most Pdots in the blue region.The reversible conversion of BTE under different light irradiation was utilized to regulate the photodynamic effect and solve the problem of photosensitivity.The prepared Ce6-BTE-doped Pdots had small size,excellent optical property,efficient ROS generation and good photoswitchable ability.The cellular uptake,cytotoxicity,and photodynamic effect of the Pdots were detected in human colon tumor cells.The experiments in vitro indicated that Ce6-BTE-doped Pdots could exert excellent photodynamic effect in ON state and reduce photosensitivity in OFF state.These results demonstrated that this nanoplatform holds the potential to be used in clinical PDT.
基金National Natural Science Foundation of China,Grant/Award Number:52207025Science and Technology Commission of Shanghai Municipality,Grant/Award Number:20YF1414700“Chen Guang”project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation,Grant/Award Number:21CGA63。
文摘The space charge accumulation in the heterogeneous insulation composed of cross-linked polyethylene(XLPE)cable and silicone rubber(SiR)accessory poses a serious threat to the safe operation of the high voltage direct current(HVDC)cable.When the cable is in heavy load,the charge transport behaviour in XLPE/SiR becomes more complicated due to the high temperature.In order to investigate the charge transport characteristics of XLPE/SiR under heavy load condition,the simultaneous measurement of space charge and relaxation current is performed on XLPE/SiR at both 70℃ and 30℃ with different polarities.The results show that the polarity of the interface charges in XLPE/SiR is always consistent with that of the SiR side electrode,and the influence of high temper-ature(70℃)caused by heavy load on the interface charge accumulation of XLPE/SiR is reversed at different polarities.The interface trap depth of XLPE/SiR is consistently greater than the bulk trap depths in both XLPE and SiR.When at high temperature of 70℃,the depth and density of interface traps increase,and the bulk traps in XLPE and SiR also exhibit increased depth.The component of polarisation relaxation current associated with space charge activity increases and exhibits longer decay time at 70℃,indicating more active and complex charge trapping-detrapping activities under heavy load condition.In this paper,an advanced simultaneous measurement is used to correlate the internal charge distribution with the external current for analysis,and the charge transport characteristics of XLPE/SiR under heavy load condition is revealed.The results can provide reference for the operation and maintenance of HVDC cable,and can also provide a basis for the space charge regulation of heterogeneous insulation at HVDC cable accessories.
基金supported by the National Natural Science Foundation of China(No.62302242)China Postdoctoral Science Foundation(No.2023M731802).
文摘Deterministic encryption(DET)allows for fast retrieval of encrypted information,but it would cause significant leakage of frequency information of the underlying data,which results in an array of inference attacks.Simply replacing DET with fully randomized encryption is often undesirable in the scenario of an encrypted database since it incurs a large overhead in query and storage.Frequency Smoothing Encryption(FSE)is a practical encryption scheme to protect frequency information.Current FSE constructions still fall short of efficiency and a reasonable security definition.We revisit FSE and propose two security definitions from both theoretical and practical perspectives.Furthermore,we adopt a novel partitioning strategy to construct a new FSE scheme to improve performance.Experimental results show that compared with others,our scheme achieves excellent query performance while attaining security against inference attacks.
基金Acknowledgements This study was supported by the University of Macao in Macao （Nos. MYRG2014-00093-FHS, MYRG 2015-00036-FHS, and MYRG2016-00110-FHS）, Macao government （Nos. FDCT 026/2014/A1 and FDCT 025/2015/A1）, and the National Natural Science Foundation of China （No. 11434017）.
文摘As a hybrid imaging technique, photoacoustic imaging （PAI） can provide multiscale morphological information of tissues, and the use of multi-spectral PAI （MSPAI） can recover the spatial distribution of chromophores of interest, such as hemoglobin within tissues. Herein, we developed a contrast agent that can very effectively combine multiscale PAI with MSPAI for a more comprehensive characterization of complex biological tissues. Specifically, we developed novel PIID-DTBT based semi-conducting polymer dots （Pdots） that show broad and strong optical absorption in the visible-light region （500-700 nm）. The performances of gold nanoparticles （GNPs） and gold nanorods （GNRs）, which have been verified as excellent photoacoustic contrast agents, were compared with that of the Pdots based on the multiscale PAI system. Both ex vivo and in vivo experiments demonstrated that the Pdots have better photoacoustic conversion efficiency at 532 nm than GNPs and showed similar photoacoustic performance with GNRs at 700 nm at the same mass concentration. Photostability and toxicity tests demonstrated that the Pdots are photostable and biocompatible. More importantly, an in vivo MSPAI experiment indicated that the Pdots have better photoacoustic performance than the blood and therefore the signals can be accurately extracted from the background of vascular-rich tissues. Our work demonstrates the great potential of Pdots as highly effective contrast agents for the precise localization of lesions relative to the blood vessels based on multiscale PAI and MSPAI.
