Transient Behavior of Ni@NiO_<i>x</i> Functionalized SrTiO₃ in Overall Water Splitting

Transients in the composition of Ni@NiO_<i>x</i> core–shell co-catalysts deposited on SrTiO₃ are discussed on the basis of state-of-the-art continuous analysis of photocatalytic water splitting, and post-XPS and TEM analyses. The formation of excessive hydrogen (H₂:O₂ ≫ 2) in the initial stages of illumination demonstrates oxidation of Ni­(OH)₂ to NiOOH (nickel oxyhydroxide), with the latter catalyzing water oxidation. A disproportionation reaction of Ni and NiOOH, yielding Ni­(OH)₂ with residual embedded Ni, occurs when illumination is discontinued, which explains repetitive transients in (excess) hydrogen and oxygen formation when illumination is reinitiated

Ratiometric Biosensor for Aggregation-Induced Emission-Guided Precise Photodynamic Therapy

Photodynamic therapy faces the barrier of choosing the appropriate irradiation region and time. In this paper, a matrix metalloproteinase-2 (MMP-2) responsive ratiometric biosensor was designed and synthesized for aggregation-induced emission (AIE)-guided precise photodynamic therapy. It was found that the biosensor presented the MMP-2 responsive AIE behavior. Most importantly, it could accurately differentiate the tumor cells from the healthy cells by the fluorescence ratio between freed tetraphenylethylene and protoporphyrin IX (PpIX, internal reference). <i>In vivo</i> study demonstrated that the biosensor could preferentially accumulate in the tumor tissue with a relative long blood retention time. Note that the intrinsic fluorescence of PpIX and MMP-2-triggered AIE fluorescence provided a real-time feedback which guided precise photodynamic therapy <i>in vivo</i> efficiently. This strategy demonstrated here opens a window in the precise medicine, especially for phototherapy

Additional file 1 of Boltzmann- and Non-Boltzmann-Based Thermometers in the First, Second and Third Biological Windows for the SrF2:Yb3+, Ho3+ Nanocrystals Under 980, 940 and 915 nm Excitations

Additional file 1: Fig. S1. Variation of upconversion emission intensity as a function of Yb3+ dopant concentration when fixed the concentration of Ho3+ (0.1 mol%). Fig. S2. The UV–vis–NIR absorption spectra of SrF2:Yb3+/Ho3+ (12/0.1 mol%) NCs. Fig. S3. The dependence of luminescence intensity at (a) 1012 nm and (c) 2020 nm of SrF2:Yb3+/Ho3+ NCs on the temperature under 980 nm excitation. Arrhenius equation is used to fit the luminescence intensity dependent on temperature at (b) 1012 nm and (d) 2020 nm

Tumor-Triggered Geometrical Shape Switch of Chimeric Peptide for Enhanced <i>in Vivo</i> Tumor Internalization and Photodynamic Therapy

Geometrical shape of nanoparticles plays an important role in cellular internalization. However, the applicability in tumor selective therapeutics is still scarcely reported. In this article, we designed a tumor extracellular acidity-responsive chimeric peptide with geometrical shape switch for enhanced tumor internalization and photodynamic therapy. This chimeric peptide could self-assemble into spherical nanoparticles at physiological condition. While at tumor extracellular acidic microenvironment, chimeric peptide underwent detachment of acidity-sensitive 2,3-dimethylmaleic anhydride groups. The subsequent recovery of ionic complementarity between chimeric peptides resulted in formation of rod-like nanoparticles. Both <i>in vitro</i> and <i>in vivo</i> studies demonstrated that this acidity-triggered geometrical shape switch endowed chimeric peptide with accelerated internalization in tumor cells, prolonged accumulation in tumor tissue, enhanced photodynamic therapy, and minimal side effects. Our results suggested that fusing tumor microenvironment with geometrical shape switch should be a promising strategy for targeted drug delivery

Improving CT-image universal lesion detection with comprehensive data and feature enhancements

As a crucial task in Computer Vision, object detection has substantially improved in recent years, with the aid of deep learning and increasingly abundant datasets. However, compared with natural image detection, medical CT images require more precision due to the obvious clinical implications. Detecting multiple lesions or clusters with relatively few training samples and indistinctive feature representation is extremely problematic. In this paper, we propose comprehensive improvements to the original YOLOv3, such as data augmentation, feature attention enhancement and feature complementarity enhancement to increase general lesion area detection performance. Ablation studies use the open DeepLesion dataset to validate these improvements and confirm the effectiveness of each amendment. Comparisons between state-of-the-art counterparts demonstrated that the proposed lesion object detector has enhanced salient accuracy (under two commonly used metrics) and an exceptional speed-accuracy trade-off. The proposed model achieved 57.5% mAP and 85.07% sensitivity at 4 false positives (FPs) per image, while running at reliable 35.6 frames per second (FPS). These findings indicate that the proposed detector is more practicable than other currently available computer aided diagnostics (CAD)

Mitochondria-Targeted Chimeric Peptide for Trinitarian Overcoming of Drug Resistance

In this report, an amphiphilic mitochondria-targeted chimeric peptide-based drug delivery system (DDS) was designed to overcome drug resistance. In vitro studies revealed that chimeric peptide could encapsulate doxorubicin (DOX) with high efficacy and target tumor mitochondria, realizing controlled release of DOX and in situ photodynamic therapy (PDT) in mitochondria. Importantly, reactive oxygen species (ROS) during PDT significantly disrupted mitochondria, leading to a dramatic decrease of intracellular adenosine 5′-triphophate (ATP). As a result, ATP-dependent efflux of DOX was remarkably inhibited. Trinitarian therapeutic strategy was developed to ablation of drug-resistant cells, that is, (1) enhanced cellular uptake of hydrophobic DOX via encapsulation in DDS, (2) combined chemo-/photodynamic therapies, and (3) suppressed generation of intracellular ATP as well as drug efflux via in situ PDT in mitochondria. This trinitarian strategy may open a new window in the fabrication of subcellular organelle destructive DDS in overcoming drug resistance

Self-Powered Electrostatic Filter with Enhanced Photocatalytic Degradation of Formaldehyde Based on Built-in Triboelectric Nanogenerators

Recently, atmospheric pollution caused by particulate matter or volatile organic compounds (VOCs) has become a serious issue to threaten human health. Consequently, it is highly desirable to develop an efficient purifying technique with simple structure and low cost. In this study, by combining a triboelectric nanogenerator (TENG) and a photocatalysis technique, we demonstrated a concept of a self-powered filtering method for removing pollutants from indoor atmosphere. The photocatalyst P25 or Pt/P25 was embedded on the surface of polymer-coated stainless steel wires, and such steel wires were woven into a filtering network. A strong electric field can be induced on this filtering network by TENG, while both electrostatic adsorption effect and TENG-enhanced photocatalytic effect can be achieved. Rhodamine B (RhB) steam was selected as the pollutant for demonstration. The absorbed RhB on the filter network with TENG in 1 min was almost the same amount of absorption achieved in 15 min without using TENG. Meanwhile, the degradation of RhB was increased over 50% under the drive of TENG. Furthermore, such a device was applied for the degradation of formaldehyde, where degradation efficiency was doubled under the drive of TENG. This work extended the application for the TENG in self-powered electrochemistry, design and concept of which can be possibly applied in the field of haze governance, indoor air cleaning, and photocatalytic pollution removal for environmental protection

Acidity-Triggered Tumor Retention/Internalization of Chimeric Peptide for Enhanced Photodynamic Therapy and Real-Time Monitoring of Therapeutic Effects

Photodynamic therapy (PDT) holds great promise in tumor treatment. Nevertheless, it remains highly desirable to develop easy-to-fabricated PDT systems with improved tumor accumulation/internalization and timely therapeutic feedback. Here, we report a tumor-acidity-responsive chimeric peptide for enhanced PDT and noninvasive real-time apoptosis imaging. Both in vitro and in vivo studies revealed that a tumor mildly acidic microenvironment could trigger rapid protonation of carboxylate anions in chimeric peptide, which led to increased ζ potential, improved hydrophobicity, controlled size enlargement, and precise morphology switching from sphere to spherocylinder shape of the chimeric peptide. All of these factors realized superfast accumulation and prolonged retention in the tumor region, selective cellular internalization, and enhanced PDT against the tumor. Meanwhile, this chimeric peptide could further generate reactive oxygen species and initiate cell apoptosis during PDT. The subsequent formation of caspase-3 enzyme hydrolyzed the chimeric peptide, achieving a high signal/noise ratio and timely fluorescence feedback. Importantly, direct utilization of the acidity responsiveness of a biofunctional Asp–Glu–Val–Asp–Gly (DEVDG, caspase-3 enzyme substrate) peptide sequence dramatically simplified the preparation and increased the performance of the chimeric peptide furthest

Activable Cell-Penetrating Peptide Conjugated Prodrug for Tumor Targeted Drug Delivery

In this paper, an activable cell-penetrating peptide (CR₈G₃PK₆, ACPP) with a shielding group of 2,3-dimethylmaleic anhydride (DMA) was conjugated with antitumor drug doxorubicin (DOX) to construct a novel prodrug (DOX-ACPP-DMA) for tumor targeted drug delivery. The shielding group of DMA linked to the primary amines of K₆ through the amide bond was used to block the cell-penetrating function of the polycationic CPP (R₈) through intramolecular electrostatic attraction at physiological pH 7.4. At tumor extracellular pH 6.8, the hydrolysis of DMA led to charge reversal, activating the pristine function of CPP for improved cellular uptake by tumor cells. Confocal laser scanning microscopy (CLSM) and flow cytometry studies revealed that the cellular uptake of DOX-ACPP-DMA was significantly enhanced after acid-triggered activation in both HeLa and COS7 cells. After cell internalization, the overexpressed intracellular proteases would further trigger drug release in cells. Both in vitro and in vivo investigations showed that the peptidic prodrug exhibited significant tumor growth inhibition and demonstrated great potential for tumor therapy

Additional file 1 of The effects of oxaliplatin-based adjuvant chemotherapy in high-risk stage II colon cancer with mismatch repair-deficient: a retrospective study

Additional file 1: Fig S1. Flow of study