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With the rapid development of image editing technology, tampering with images has become easier. Maliciously tampered images lead to serious security problems (e.g., when used as evidence). The current mainstream methods of image tampering are divided into three types which are copy‐move, splicing and removal. Many image tampering detection methods can only detect one type of image tampering. Additionally, some methods learn features by suppressing image content, which can result in false positives when identifying tampered areas. In this paper, the authors propose a novel framework named the dual supervision neural network (DS‐Net) to localize the tampered regions of images tampered by the three tampering methods mentioned above. First, to extract richer multiscale information, the authors add skip connections to the atrous spatial pyramid pooling (ASPP) module. Second, a channel attention mechanism is introduced to dynamically weigh the results generated by ASPP. Finally, the authors build additional supervised branches for high‐level features to further enhance the extraction of these high‐level features before fusing them with low‐level features. The authors conduct experiments on various standard datasets. Through extensive experiments, the results show that the AUC scores reach 86.4%, 95.3% and 99.6% for CASIA, COVERAGE and NIST16 datasets, respectively, and the F1 scores are 56.0%, 73.4% and 82.7%, respectively. The results demonstrate that the authors' method can accurately locate tampered regions and achieve better performance on various datasets than other methods of the same type. [ABSTRACT FROM AUTHOR]

Radiotherapy (RT) is an effective and widely applied cancer treatment strategy in clinic. However, it usually suffers from radioresistance of tumor cells and severs side effects of excessive radiation dose. Therefore, it is highly significant to improve radiotherapeutic performance and monitor real‐time tumor response, achieving precise and safe RT. Herein, an X‐ray responsive radio‐pharmaceutical molecule containing chemical radiosensitizers of diselenide and nitroimidazole (BBT‐IR/Se‐MN) is reported. BBT‐IR/Se‐MN exhibits enhanced radiotherapeutic effect via a multifaceted mechanisms and self‐monitoring ROS levels in tumors during RT. Under X‐ray irradiation, the diselenide produces high levels of ROS, leading to enhanced DNA damage of cancer cell. Afterwards, the nitroimidazole in the molecule inhibits the damaged DNA repair, offering a synergetic radiosensitization effect of cancer. Moreover, the probe shows low and high NIR‐II fluorescence ratios in the absence and presence of ROS, which is suitable for precise and quantitative monitoring of ROS during sensitized RT. The integrated system is successfully applied for radiosensitization and the early prediction of in vitro and in vivo RT efficacy. [ABSTRACT FROM AUTHOR]

Radiotherapy (RT) is an effective and widely applied cancer treatment strategy in clinic. However, it usually suffers from radioresistance of tumor cells and severs side effects of excessive radiation dose. Therefore, it is highly significant to improve radiotherapeutic performance and monitor real‐time tumor response, achieving precise and safe RT. Herein, an X‐ray responsive radio‐pharmaceutical molecule containing chemical radiosensitizers of diselenide and nitroimidazole (BBT‐IR/Se‐MN) is reported. BBT‐IR/Se‐MN exhibits enhanced radiotherapeutic effect via a multifaceted mechanisms and self‐monitoring ROS levels in tumors during RT. Under X‐ray irradiation, the diselenide produces high levels of ROS, leading to enhanced DNA damage of cancer cell. Afterwards, the nitroimidazole in the molecule inhibits the damaged DNA repair, offering a synergetic radiosensitization effect of cancer. Moreover, the probe shows low and high NIR‐II fluorescence ratios in the absence and presence of ROS, which is suitable for precise and quantitative monitoring of ROS during sensitized RT. The integrated system is successfully applied for radiosensitization and the early prediction of in vitro and in vivo RT efficacy. [ABSTRACT FROM AUTHOR]

With the rapid development of manipulation technologies, the generation of Deep Fake videos is more accessible than ever. As a result, face forgery detection becomes a challenging task, attracting a significant amount of attention from researchers worldwide. However, most previous work, consisting of convolutional neural networks (CNN), is not sufficiently discriminative and cannot fully utilise subtle clues and similar textures during the process of facial forgery detection. Moreover, these methods cannot simultaneously consider accuracy and time efficiency. To address such problems, we propose a novel framework named FPC‐Net to extract some meaningful and unnatural expressions in local regions. This framework utilises CNN, long short‐term memory (LSTM), channel groups loss (CG‐Loss) and adaptive feature fusion to detect face forgery videos. First, the proposed method exploits spatial features by CNN, and a channel‐wise attention mechanism is employed to separate channels. Specifically, with the help of channel groups loss, the channels are divided into two groups, each representing a specific class. Second, LSTM is applied to learn the correlation of spatial features. Finally, the correlation of features is mapped into other latent spaces. Through a lot of experiments, the results are that the detection speed of the proposed method reaches 420 FPS and the auc scores achieve best performance of 99.7%, 99.9%, 94.7%, and 82.0% on Raw Celeb‐DF, Raw Face Forensics++, F2F and NT datasets respectively. The experimental results demonstrate that the proposed framework has great time efficiency performance while improving the detection performance compared with other frame‐level methods in most cases. [ABSTRACT FROM AUTHOR]

Recently, several in‐loop filtering algorithms based on convolutional neural network (CNN) have been proposed to improve the efficiency of HEVC (High Efficiency Video Coding). Conventional CNN‐based filters only apply a single model to the whole image, which cannot adapt well to all local features from the image. To solve this problem, an in‐loop filtering algorithm based on a dynamic convolutional capsule network (DCC‐net) is proposed, which embeds localized dynamic routing and dynamic segmentation algorithms into capsule network, and integrate them into the HEVC hybrid video coding framework as a new in‐loop filter. The proposed method brings average 7.9% and 5.9% BD‐BR reductions under all intra (AI) and random access (RA) configurations, respectively, as well as, 0.4 dB and 0.2 dB BD‐PSNR gains, respectively. In addition, the proposed algorithm has an outstanding performance in terms of time efficiency. [ABSTRACT FROM AUTHOR]

The therapeutic efficacy of natural killer (NK) cells‐based immunotherapy is greatly related with the survival of transplanted NK cells. However, no effective strategy was reported to monitor NK cell viability in adoptive immunotherapy in vivo. Herein, we develop a ratiometric NIR‐II fluorescence imaging strategy to quantitively track and visualize the adoptive NK cell viability in vivo in real‐time. The nanoprobe consists of lanthanide‐based down‐conversion nanoparticles (DCNP) coated with IR786s, a reactive oxygen species (ROS) sensitive to NIR dye, which was directly labeled with NK cells. Upon cell death, the excessive ROS generation occurred within NK cells, along with IR786s degradation, turning on NIR‐II fluorescent signal at 1550 nm of DCNP under 808‐nm excitation, while the fluorescent signal at 1550 nm of DCNP under 980‐nm excitation was stable. Such an intracellular ROS‐induced ratiometric NIR‐II fluorescent signal was validated to correlate well with NK cell viability in vivo. Using this nanoreporter, we further demonstrated that co‐treatment with IL‐2, IL‐15, and IL‐21 could improve NK cell viability in vivo, achieving enhanced immunotherapy for orthotopic hepatocellular carcinoma. Overall, this strategy allows for longitudinal and quantitative tracking of NK cell viability in NK cell‐based immunotherapy. [ABSTRACT FROM AUTHOR]

The therapeutic efficacy of natural killer (NK) cells‐based immunotherapy is greatly related with the survival of transplanted NK cells. However, no effective strategy was reported to monitor NK cell viability in adoptive immunotherapy in vivo. Herein, we develop a ratiometric NIR‐II fluorescence imaging strategy to quantitively track and visualize the adoptive NK cell viability in vivo in real‐time. The nanoprobe consists of lanthanide‐based down‐conversion nanoparticles (DCNP) coated with IR786s, a reactive oxygen species (ROS) sensitive to NIR dye, which was directly labeled with NK cells. Upon cell death, the excessive ROS generation occurred within NK cells, along with IR786s degradation, turning on NIR‐II fluorescent signal at 1550 nm of DCNP under 808‐nm excitation, while the fluorescent signal at 1550 nm of DCNP under 980‐nm excitation was stable. Such an intracellular ROS‐induced ratiometric NIR‐II fluorescent signal was validated to correlate well with NK cell viability in vivo. Using this nanoreporter, we further demonstrated that co‐treatment with IL‐2, IL‐15, and IL‐21 could improve NK cell viability in vivo, achieving enhanced immunotherapy for orthotopic hepatocellular carcinoma. Overall, this strategy allows for longitudinal and quantitative tracking of NK cell viability in NK cell‐based immunotherapy. [ABSTRACT FROM AUTHOR]

To date, hydrogen (H2) therapy has received widespread attention. However, X‐ray triggered sustainable H2‐producing materials with controlled release for cancer treatment have not been reported. Herein, an X‐ray triggered sustainable in situ H2 producing platform, Au NR‐TiO2@ZnS:Cu,Co‐A(Au‐TiO2@ZnS), composed of Au‐amorphous TiO2 nano‐dumbbell‐shaped heterostructure coated with long afterglow particles, was developed for cancer synergistic H2‐radiotherapy. The mechanism of H2 production was verified by theoretical calculations and in vitro experiments. Changes in the apoptosis pathway caused by the synergistic effect of H2 and radiotherapy were reported. Guided by its excellent photoacoustic imaging capabilities, mice with orthotopic liver cancer achieved excellent therapeutic effects and low inflammatory side effects, suggesting that Au‐TiO2@ZnS has promising application potential for cancer treatment and prognosis. [ABSTRACT FROM AUTHOR]

To date, hydrogen (H2) therapy has received widespread attention. However, X‐ray triggered sustainable H2‐producing materials with controlled release for cancer treatment have not been reported. Herein, an X‐ray triggered sustainable in situ H2 producing platform, Au NR‐TiO2@ZnS:Cu,Co‐A(Au‐TiO2@ZnS), composed of Au‐amorphous TiO2 nano‐dumbbell‐shaped heterostructure coated with long afterglow particles, was developed for cancer synergistic H2‐radiotherapy. The mechanism of H2 production was verified by theoretical calculations and in vitro experiments. Changes in the apoptosis pathway caused by the synergistic effect of H2 and radiotherapy were reported. Guided by its excellent photoacoustic imaging capabilities, mice with orthotopic liver cancer achieved excellent therapeutic effects and low inflammatory side effects, suggesting that Au‐TiO2@ZnS has promising application potential for cancer treatment and prognosis. [ABSTRACT FROM AUTHOR]

The subcellular distributions of nanoparticles in the brain are important for their biological application. We synthesized and characterized the superparamagnetic iron oxide nanoparticles (SPIONs) modified with poly (ethylene glycol) (PEG) and polyethylenimine (PEI) (PEG/PEI-SPIONs), and with dimyristoylphosphatidylcholine (DMPC) (DMPC-SPIONs). The nanoparticles were unilaterally injected into the left substantia nigra of rat brains. The distributions of the nanoparticles in the left brains of the rats were examined by ICP-OES (inductively coupled plasma optical emission spectrometer) and TEM (transmission electron microscopy) at 24 h after the injection. Iron was found in the olfactory bulb, temporal lobe, frontal cortex, thalamus and brain stem at 24 h after the injection of DMPC-SPIONs and PEG/PEI-SPIONs. In the rat substantia nigra, most DMPC-SPIONs were distributed in and on the myelin sheath around axons or on cell membranes, some were in cells. As a comparison, less iron was found in the rat brains at 24 h after the injection of PEG/PEI-SPIONs. Our experiments suggest DMPC modification on SPIONs be a safe and effective method for increasing SPIONs distribution on the cell membranes. This work is encouraging for further study on using DMPC-SPIONs for efficient drug delivery or for deep brain stimulation of neurons in a magnetic field. [ABSTRACT FROM AUTHOR]

Real‐time monitoring the therapeutic process of sonodynamic therapy (SDT) is essential to optimize the treatment course in time and eventually improve the efficacy. The generation of singlet oxygen (1O2) is a quintessential characteristic of SDT, which permits non‐invasive monitoring of SDT by real‐time imaging of 1O2 inside the tumor. Nonetheless, the majority of probes are unable to measure 1O2 in real time because of its short half‐life and strong oxidative capacity. Here, the study constructs a ratiometric nanoplatform (DTPI) utilizing two fluorescent probes and the sonosensitizer TiO2. The poisonous 1O2 generated by DTPI following ultrasonic (US) radiation efficiently destroys tumor cells. The structural disruption of fluorescent dye IR‐1061 by 1O2 leads to a reduction in the DTPI fluorescence signal at 1100 nm, while US radiation has no impact on the fluorescence signal at 1550 nm. Thus, DTPI provides a precise and consistent reflection of the treatment efficacy at the tumor site, leveraging the ratiometric fluorescence signal and variations in oxygen content throughout the treatment process. This ratiometric‐fluorescence‐based reflection strategy establishes an effective and dependable platform for the real‐time monitoring and assessment of the cancer therapeutic effect through ratiometric probes. [ABSTRACT FROM AUTHOR]

Delays in evaluating cancer response to radiotherapy (RT) usually reduce therapy effect or miss the right time for treatment optimization. Hence, exploring timely and accurate methods enabling one to gain insights of RT response are highly desirable. In this study, we have developed an apoptosis enzyme (caspase‐3) activated nanoprobe for early evaluation of RT efficacy. The nanoprobe bridged the nanogapped gold nanoparticles (AuNNPs) and the second near‐infrared window (NIR‐II) fluorescent (FL) molecules (IR‐1048) through a caspase‐3 specific peptide sequence (DEVD) (AuNNP@DEVD‐IR1048). After X‐ray irradiation, caspase‐3 was activated to cut DEVD, turning on both NIR‐II FL and PA imaging signals. The increased NIR‐II FL/PA signals exhibited a positive correlation with the content of caspase‐3. Moreover, the amount of the activated caspase‐3 was negatively correlated with the tumor size. The results underscore the role of the caspase‐3 activated by X‐ray irradiation in bridging the imaging signals variation and tumor inhibition rate. Overall, activatable NIR‐II FL/PA imaging was successfully used to timely predict and evaluate the RT efficacy. The evaluation system based on biomarker‐triggered living imaging has the capacity to guide treatment decisions for numerous cancer types. [ABSTRACT FROM AUTHOR]

Delays in evaluating cancer response to radiotherapy (RT) usually reduce therapy effect or miss the right time for treatment optimization. Hence, exploring timely and accurate methods enabling one to gain insights of RT response are highly desirable. In this study, we have developed an apoptosis enzyme (caspase‐3) activated nanoprobe for early evaluation of RT efficacy. The nanoprobe bridged the nanogapped gold nanoparticles (AuNNPs) and the second near‐infrared window (NIR‐II) fluorescent (FL) molecules (IR‐1048) through a caspase‐3 specific peptide sequence (DEVD) (AuNNP@DEVD‐IR1048). After X‐ray irradiation, caspase‐3 was activated to cut DEVD, turning on both NIR‐II FL and PA imaging signals. The increased NIR‐II FL/PA signals exhibited a positive correlation with the content of caspase‐3. Moreover, the amount of the activated caspase‐3 was negatively correlated with the tumor size. The results underscore the role of the caspase‐3 activated by X‐ray irradiation in bridging the imaging signals variation and tumor inhibition rate. Overall, activatable NIR‐II FL/PA imaging was successfully used to timely predict and evaluate the RT efficacy. The evaluation system based on biomarker‐triggered living imaging has the capacity to guide treatment decisions for numerous cancer types. [ABSTRACT FROM AUTHOR]

Sonodynamic bacterial inactivation, a reactive oxygen species (ROS)‐empowered approach featuring high penetration depth and low health risk, is explored for antibiotic‐free antibacterial treatment. However, the low yield and insufficient diffusion of ROS negatively affect the antibacterial efficacy of sonodynamic treatment, thus hindering its further development. Here an actuator‐integrated mechanism is proposed for enhancing the sonodynamic efficacy of loaded sonosensitizers through motion‐induced hydrodynamic effects, demonstrated by a porphyrin‐decorated gold nanomotor, which can produce ROS for bacterial inactivation while performing multimodal motion via actuation using low‐frequency ultrasound. Corroborated by numerical simulation, the experimental results show that the motor's stirring motion significantly increases the yield and diffusion of ROS through fluid flow and frequent interactions between the motor and bacterial targets, resulting in doubled antibacterial efficiency in comparison to a stationary motor. Furthermore, the flow‐induced shear forces combined with the frequent interactions constitute a source of mechanical damage and can form a synergy with the antibacterial properties of ROS, enabling an efficient biofilm eradication that is inaccessible by freely suspended porphyrin. In conclusion, this study reports a motion‐based strategy to enhance sonodynamic efficacy and provides proof of concept using a sonodynamic gold nanomotor powered by ultrasound. [ABSTRACT FROM AUTHOR]

Matrix factorization has always been an encouraging field, which attempts to extract discriminative features from high-dimensional data. However, it suffers from negative generalization ability and high computational complexity when handling large-scale data. In this paper, we propose a learnable deep matrix factorization via the projected gradient descent method, which learns multi-layer low-rank factors from scalable metric distances and flexible regularizers. Accordingly, solving a constrained matrix factorization problem is equivalently transformed into training a neural network with an appropriate activation function induced from the projection onto a feasible set. Distinct from other neural networks, the proposed method activates the connected weights not just the hidden layers. As a result, it is proved that the proposed method can learn several existing well-known matrix factorizations, including singular value decomposition, convex, nonnegative and semi-nonnegative matrix factorizations. Finally, comprehensive experiments demonstrate the superiority of the proposed method against other state-of-the-arts. • Propose a learnable method to approximate several popular matrix factorizations. • Construct an easy-built end-to-end architecture for low-rank learning. • Provide a new perspective for computing hierarchical low-rank matrix factors. • Validate its superiority to matrix factorizations and deep clustering approaches. [ABSTRACT FROM AUTHOR]

Real-time imaging of reactive oxygen species (ROS) during cisplatin chemotherapy of cancer is imperative to fully reveal their functions in the biological response to cisplatin. Currently, using a bioluminescent probe for real-time imaging of a specific ROS in vivo during cisplatin chemotherapy has not been achieved. Herein, three bioluminescent probes, F Probe , N Probe and P Probe were synthesized for real-time imaging of the primary ROS, O 2 •−. They all consisted of a bioluminescent emitter D -luciferin (D -LH 2) and an O 2 •−-recognition group, and their bioluminescent signal could be turned on in response to O 2 •−. In vitro results indicated that P Probe was the most suitable one among the three probes for detection of O 2 •−, with high sensitivity, excellent selectivity and stability. P Probe was then successfully applied for real-time imaging of O 2 •− in both cancer cells and tumors during cisplatin chemotherapy. The imaging results demonstrated that O 2 •− amount in cancer cells increased with the increasing dose of cisplatin, and that cisplatin-induced upregulation of O 2 •− level in cancer cells was upstream of the cancer-killing pathway of cisplatin. We envision that P Probe may serve as an elucidative tool to further explore the role of O 2 •− in cisplatin chemotherapy. • Three turn-on bioluminescent probes were synthesized for real-time imaging of the primary ROS, O 2 •−. • P Probe could detect O 2 •− with high sensitivity, excellent selectivity and stability. • We successfully applied P Probe for real-time imaging of O 2 •− during cisplatin chemotherapy both in cancer cells and in vivo. • Our study provides new elucidative tool for further explore the role of O 2 •− in cisplatin chemotherapy. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Chemiluminescence (CL) is a promising tool for diagnostics and sensing due to its inherent excitation light‐free. However, most CL probes emit exclusively visible light with limited penetration depth, hindering their broad application for in vivo deep tissue imaging. This work reports an activated unimolecular CL probe (CL‐P) that emits light in the near‐infrared (NIR) region allowing a superior real‐time visualization and detection of NAD(P)H quinone oxidoreductase 1 (NQO1) in vivo. The NQO1‐specific trimethyl‐locked quinone is a lock for masking the NQO1 trigger site, and it was conjugated on the NIR Schaap's dioxetane chemiluminophore, achieving not only a subtle signal‐to‐noise ratio even at a depth of 15 mm in the chicken breast tissues, but also sensitively detecting the positive expression of NQO1 in A549 cells. CL‐P has been successfully used for visualizing the aberrantly expressed NQO1 in subcutaneous xenograft A549 tumors. To our knowledge, this is the first work reporting the detection of NQO1 activity in the NIR region by unimolecular CL mode. Overall, the NQO1‐activated visualization platform provides a guideline to transform a unimolecular CL sensor into a licensed imaging agent for the in vivo detection of enzyme‐related diseases. [ABSTRACT FROM AUTHOR]

Delays in evaluating cancer response to radiotherapy (RT) usually reduce therapy effect or miss the right time for treatment optimization. Hence, exploring timely and accurate methods enabling one to gain insights of RT response are highly desirable. In this study, we have developed an apoptosis enzyme (caspase‐3) activated nanoprobe for early evaluation of RT efficacy. The nanoprobe bridged the nanogapped gold nanoparticles (AuNNPs) and the second near‐infrared window (NIR‐II) fluorescent (FL) molecules (IR‐1048) through a caspase‐3 specific peptide sequence (DEVD) (AuNNP@DEVD‐IR1048). After X‐ray irradiation, caspase‐3 was activated to cut DEVD, turning on both NIR‐II FL and PA imaging signals. The increased NIR‐II FL/PA signals exhibited a positive correlation with the content of caspase‐3. Moreover, the amount of the activated caspase‐3 was negatively correlated with the tumor size. The results underscore the role of the caspase‐3 activated by X‐ray irradiation in bridging the imaging signals variation and tumor inhibition rate. Overall, activatable NIR‐II FL/PA imaging was successfully used to timely predict and evaluate the RT efficacy. The evaluation system based on biomarker‐triggered living imaging has the capacity to guide treatment decisions for numerous cancer types. [ABSTRACT FROM AUTHOR]

Accurate diagnosis and effective treatment of primary liver tumors are of great significance, and optical imaging has been widely employed in clinical imaging-guided surgery for liver tumors. The second near-infrared window (NIR-II) emissive AIEgen photosensitizers have attracted a lot of attention with higher-resolution bioimaging and deeper penetration. NIR-II aggregation-induced emission-based luminogen (AIEgen) photosensitizers have better phototherapeutic effects and accuracy of the image-guided surgery/phototherapy. Herein, an NIR-II AIEgen phototheranostic dot was proposed for NIR-II imaging-guided resection surgery and phototherapy for orthotopic hepatic tumors. Compared with indocyanine green (ICG), the AIEgen dots showed bright and sharp NIR-II emission at 1250 nm, which extended to 1600 nm with high photostability. Moreover, the AIEgen dots efficiently generated reactive oxygen species (ROS) for photodynamic therapy. Investigations of orthotopic liver tumors in vitro and in vivo demonstrated that AIEgen dots could be employed both for imaging-guided tumor surgery of early-stage tumors and for 'downstaging' intention to reduce the size. Moreover, the therapeutic strategy induced complete inhibition of orthotopic tumors without recurrence and with few side effects. [ABSTRACT FROM AUTHOR]

Controlling the structural order of nanoparticles (NPs), morphology, and composition is of paramount significance in tailoring the physical properties of nanoassembly. However, the commonly reported symmetrical nanocomposites often suffer an interference or sacrifice of the photophysical properties of the original components. To address this challenge, we developed a novel type of organic‐inorganic Janus nanocomposite (JNCP) with an asymmetric architecture, offering unique features such as the precisely controlled localization of components, combined modular optical properties, and independent stimuli. As a proof of concept, JNCPs were prepared by incorporating two photoacoustic (PA) imaging agents, namely an organic semiconducting dye and responsive gold nanoparticles (AuNP) assembly in separate compartments of JNCP. Theoretical simulation results confirmed that the formation mechanism of JNCPs arises from the entropy equilibrium in the system. The AuNP assembly generated a PA images with the variation of pH, while the semiconducting molecule served as an internal PA standard agent, leading to ratiometric PA imaging of pH. JNCP based probe holds great potential for real‐time and accurate detection of diverse biological targets in living systems. [ABSTRACT FROM AUTHOR]

Controlling the structural order of nanoparticles (NPs), morphology, and composition is of paramount significance in tailoring the physical properties of nanoassembly. However, the commonly reported symmetrical nanocomposites often suffer an interference or sacrifice of the photophysical properties of the original components. To address this challenge, we developed a novel type of organic‐inorganic Janus nanocomposite (JNCP) with an asymmetric architecture, offering unique features such as the precisely controlled localization of components, combined modular optical properties, and independent stimuli. As a proof of concept, JNCPs were prepared by incorporating two photoacoustic (PA) imaging agents, namely an organic semiconducting dye and responsive gold nanoparticles (AuNP) assembly in separate compartments of JNCP. Theoretical simulation results confirmed that the formation mechanism of JNCPs arises from the entropy equilibrium in the system. The AuNP assembly generated a PA images with the variation of pH, while the semiconducting molecule served as an internal PA standard agent, leading to ratiometric PA imaging of pH. JNCP based probe holds great potential for real‐time and accurate detection of diverse biological targets in living systems. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O2) has a potent anticancer effect, but photosensitized generation of 1O2 is inhibited by tumor hypoxia and limited light penetration depth. Despite the potential of chemodynamic therapy (CDT) to circumvent these issues by exploration of 1O2‐producing catalysts, engineering efficient CDT agents is still a formidable challenge since most catalysts require specific pH to function and become inactivated upon chelation by glutathione (GSH). Herein, we present a catalytic microenvironment‐tailored nanoreactor (CMTN), constructed by encapsulating MoO42− catalyst and alkaline sodium carbonate within liposomes, which offers a favorable pH condition for MoO42−‐catalyzed generation of 1O2 from H2O2 and protects MoO42− from GSH chelation owing to the impermeability of liposomal lipid membrane to ions and GSH. H2O2 and 1O2 can freely cross the liposomal membrane, allowing CMTN with a built‐in NIR‐II ratiometric fluorescent 1O2 sensor to achieve monitored tumor CDT. [ABSTRACT FROM AUTHOR]

Singlet oxygen (1O2) has a potent anticancer effect, but photosensitized generation of 1O2 is inhibited by tumor hypoxia and limited light penetration depth. Despite the potential of chemodynamic therapy (CDT) to circumvent these issues by exploration of 1O2‐producing catalysts, engineering efficient CDT agents is still a formidable challenge since most catalysts require specific pH to function and become inactivated upon chelation by glutathione (GSH). Herein, we present a catalytic microenvironment‐tailored nanoreactor (CMTN), constructed by encapsulating MoO42− catalyst and alkaline sodium carbonate within liposomes, which offers a favorable pH condition for MoO42−‐catalyzed generation of 1O2 from H2O2 and protects MoO42− from GSH chelation owing to the impermeability of liposomal lipid membrane to ions and GSH. H2O2 and 1O2 can freely cross the liposomal membrane, allowing CMTN with a built‐in NIR‐II ratiometric fluorescent 1O2 sensor to achieve monitored tumor CDT. [ABSTRACT FROM AUTHOR]

We have synthesized a PEGylated, phenylboronic acid modified L‐DOPA pro‐antioxidant (pPAD) that can self‐assemble into nanoparticles (pPADN) for the loading of a model glucocorticoid dexamethasone (Dex) through 1,3‐diol/phenylboronic acid chemistry and hydrophobic interactions for more effective treatment of inflammation. Upon exposure to ROS, pPADN convert into the active form of L‐DOPA, and a cascade of oxidative reactions transform it into antioxidative melanin‐like materials. Concomitantly, the structural transformation of pPADN triggers the specific release of Dex, along with the acidic pH of inflammatory tissue. In a rat model of osteoarthritis, Dex‐loaded pPADN markedly mitigate synovial inflammation, suppress joint destruction and cartilage matrix degradation, with negligible in vivo toxicity. Moreover, in situ structural transformation makes pPADN suitable for noninvasive monitoring of therapeutic effects as a photoacoustic imaging contrast agent. [ABSTRACT FROM AUTHOR]

We have synthesized a PEGylated, phenylboronic acid modified L‐DOPA pro‐antioxidant (pPAD) that can self‐assemble into nanoparticles (pPADN) for the loading of a model glucocorticoid dexamethasone (Dex) through 1,3‐diol/phenylboronic acid chemistry and hydrophobic interactions for more effective treatment of inflammation. Upon exposure to ROS, pPADN convert into the active form of L‐DOPA, and a cascade of oxidative reactions transform it into antioxidative melanin‐like materials. Concomitantly, the structural transformation of pPADN triggers the specific release of Dex, along with the acidic pH of inflammatory tissue. In a rat model of osteoarthritis, Dex‐loaded pPADN markedly mitigate synovial inflammation, suppress joint destruction and cartilage matrix degradation, with negligible in vivo toxicity. Moreover, in situ structural transformation makes pPADN suitable for noninvasive monitoring of therapeutic effects as a photoacoustic imaging contrast agent. [ABSTRACT FROM AUTHOR]

Janus nanogap gold nanoparticles (JAuNNPs) with varying proportions of Au shell coverage of (ca. 100/75/50/25 %) are presented. The internal nanogap between the partial Au shell and core caused asymmetric optical behavior; tunability depends on the degree of Au shell coverage and structural asymmetry. The shell‐to‐shell or core‐to‐core JAuNNDs(50 %) were self‐assembled from amphiphilic JAuNNPs(50 %) by tuning the hydrophilic and hydrophobic polymer brushes on the Au core or shell. The positions of electromagnetic field enhancement of JAuNNDs varied with geometrical configurations because of hybridized plasmonic coupling effects. Furthermore, DNA linkers were utilized to form JAuNND12(50 %). By combining with Raman molecules, ratiometric SERS signals could be generated, enabling JAuNND12(50 %) to image the distribution of miR‐21 in living cells and tumors. Asymmetric JAuNNPs allowed facile conjugation of various linkage molecules to fabricate dimeric nanostructures. [ABSTRACT FROM AUTHOR]

Janus nanogap gold nanoparticles (JAuNNPs) with varying proportions of Au shell coverage of (ca. 100/75/50/25 %) are presented. The internal nanogap between the partial Au shell and core caused asymmetric optical behavior; tunability depends on the degree of Au shell coverage and structural asymmetry. The shell‐to‐shell or core‐to‐core JAuNNDs(50 %) were self‐assembled from amphiphilic JAuNNPs(50 %) by tuning the hydrophilic and hydrophobic polymer brushes on the Au core or shell. The positions of electromagnetic field enhancement of JAuNNDs varied with geometrical configurations because of hybridized plasmonic coupling effects. Furthermore, DNA linkers were utilized to form JAuNND12(50 %). By combining with Raman molecules, ratiometric SERS signals could be generated, enabling JAuNND12(50 %) to image the distribution of miR‐21 in living cells and tumors. Asymmetric JAuNNPs allowed facile conjugation of various linkage molecules to fabricate dimeric nanostructures. [ABSTRACT FROM AUTHOR]

Detection of glutathione (GSH) in the body is essential to accurately map the redox state of cells and real‐time visualization of physiological and pathological conditions in vivo. However, traditional fluorescence (FL) imaging in the near‐infrared I region (NIR‐I, 650–900 nm) is difficult to quantitively visualize GSH in vivo due to the tissue autofluorescence background and disastrous photon scattering. Herein, a NIR‐IIb (1500–1700 nm) nanoprobe consisting of 4‐nitrophenol‐Cy7 (NPh) conjugated lanthanide‐based downconversion nanoparticles (DCNP@NPh‐PEG) is developed for in vivo ratiometric imaging of GSH. In the presence of GSH, NPh shows responsively enhanced FL emission at 808 nm, thus enhancing FL signal at 1550 nm of DCNPs excited by 808 nm (F1550, 808Ex) through non‐radiative energy transfer (NRET) effect, while the fluorescence of DCNP at 1550 nm excited by 980 nm laser (F1550, 980Ex) is stable because no NRET occurred. The ratiometric F1550, 980Ex/F1550, 808Ex value exhibits a linearship with GSH concentration ranged from 0–24 mm with detection limit of 0.3 mm. The NIR‐IIb nanoprobe has excellent performance in detecting and imaging GSH in both subcutaneous tumor and orthotopic colon tumor in vivo with high accuracy and resolution. The design strategy of the ratiometric NIR‐II FL nanoprobe based on the activated FERT effect provides a reliable tool for the development of NIR‐II nanoprobes for accurate biosensing in vivo. [ABSTRACT FROM AUTHOR]

Excessive production of oxidative species alters the normal redox balance and leads to diseases, such as chronic inflammation and cancer. Oxidative species are short‐lived species, which makes direct, precise, and real‐time measurements difficult. Herein, we report a novel core–satellite gold nanostructure for dual, ratiometric surface‐enhanced Raman scattering (SERS) and photoacoustic (PA) imaging to enable the precise detection of inflammation/cancer‐related H2O2. The combination of H2O2‐activated second near‐infrared (NIR‐II) PA imaging and SERS imaging enables the differentiation between the inflamed region and normal tissue with high accuracy. The mesoporous silica shell of the nanoprobe could be used to deliver drugs to the target area to precisely treat disease. Therefore, this core–satellite nanostructure can not only quantitatively and precisely monitor H2O2 produced in inflammation, tumor, and osteoarthritis in rabbits in real‐time, but can also be used to track the progress of the anti‐inflammatory treatment in real‐time. [ABSTRACT FROM AUTHOR]

Excessive production of oxidative species alters the normal redox balance and leads to diseases, such as chronic inflammation and cancer. Oxidative species are short‐lived species, which makes direct, precise, and real‐time measurements difficult. Herein, we report a novel core–satellite gold nanostructure for dual, ratiometric surface‐enhanced Raman scattering (SERS) and photoacoustic (PA) imaging to enable the precise detection of inflammation/cancer‐related H2O2. The combination of H2O2‐activated second near‐infrared (NIR‐II) PA imaging and SERS imaging enables the differentiation between the inflamed region and normal tissue with high accuracy. The mesoporous silica shell of the nanoprobe could be used to deliver drugs to the target area to precisely treat disease. Therefore, this core–satellite nanostructure can not only quantitatively and precisely monitor H2O2 produced in inflammation, tumor, and osteoarthritis in rabbits in real‐time, but can also be used to track the progress of the anti‐inflammatory treatment in real‐time. [ABSTRACT FROM AUTHOR]

Excessive production of reactive oxygen species such as H2O2 is the pathological basis of chronic inflammatory diseases, as well as bacterial infection‐induced inflammation. Therefore, the in situ H2O2 level is a reliable biomarker of inflammatory responses, and its real‐time measurement can monitor disease progression and improve therapeutic outcomes in inflammation‐linked diseases. However, the currently used strategies for the diagnosis of inflammation is mainly through routine blood test, which are limited in determining the inflammation status and cannot provide comprehensive quantitative information. In this work, a novel H2O2‐responsive theranostic nanoplatform comprising Ag shell coated Pd‐tipped gold nanorods (Au–Pd@Ag NR) is developed. The etching and oxidation of the Ag shell by H2O2 release the Ag ions, which effectively kill bacteria in vivo and trigger their absorption variation at 700 and 1260 nm. The ratiometric photoacoustic (PA) imaging at 1260 and 700 nm (PA1260/PA700) accurately quantifies H2O2 in a mice model of bacterial infection and abdomen inflammation, even in a rabbit model of osteoarthritis. The H2O2 activated second near‐infrared (NIR‐II) PA images of the probe can further precisely differentiate the inflammation region and normal tissue. This nanoplatform not only can quantify H2O2 during inflammation but also act as a potent antibacterial agent. [ABSTRACT FROM AUTHOR]

Superparamagnetic iron oxide nanoparticles (SPIONs) conjugated with hyaluronic acid (HA) functional groups have potential applications as cell targeting materials. However, SPIONs incubated with high-molecular weight HA can result in severe agglomeration. In this work, we found that when modified with degraded HA (hyaluronan oligosaccharides (oHAs)), the nanoparticles were uniformly dispersed with small hydrodynamic sizes, and the oHA-modified SPIONs exerted minimal cytotoxicity. With the same functional groups as HA, the oHA-modified SPIONs may have various biomedical applications. [ABSTRACT FROM AUTHOR]

Recent reports have shown that intracellular, (super)paramagnetic ferritin nanoparticles can gate TRPV1, a non-selective cation channel, in a magnetic field. Here, we report the effects of differing field strength and frequency as well as chemical inhibitors on channel gating using a Ca2+-sensitive promoter to express a secreted embryonic alkaline phosphatase (SEAP) reporter. Exposure of TRPV1-ferritin-expressing HEK-293T cells at 30 °C to an alternating magnetic field of 501 kHz and 27.1 mT significantly increased SEAP secretion by ~ 82% relative to control cells, with lesser effects at other field strengths and frequencies. Between 30–32 °C, SEAP production was strongly potentiated 3.3-fold by the addition of the TRPV1 agonist capsaicin. This potentiation was eliminated by the competitive antagonist AMG-21629, the NADPH oxidase assembly inhibitor apocynin, and the reactive oxygen species (ROS) scavenger N-acetylcysteine, suggesting that ROS contributes to magnetogenetic TRPV1 activation. These results provide a rational basis to address the heretofore unknown mechanism of magnetogenetics. [ABSTRACT FROM AUTHOR]