Boosting exciton dissociation and charge transfer in CsPbBr3 QDs via ferrocene derivative ligation for CO2 photoreduction.

Photo-catalytic CO2 reduction with perovskite quantum dots (QDs) shows potential for solar energy storage, but it encounters challenges due to the intricate multi-electron photoreduction processes and thermodynamic and kinetic obstacles associated with them. This study aimed to improve photo-catalytic performance by addressing surface barriers and utilizing multiple-exciton generation in perovskite QDs. A facile surface engineering method was employed, involving the grafting of ferrocene carboxylic acid (FCA) onto CsPbBr3 (CPB) QDs, to overcome limitations arising from restricted multiple-exciton dissociation and inefficient charge transfer dynamics. Kelvin Probe Force Microscopy and XPS spectral confirmed successfully creating an FCA-modulated microelectric field through the Cs active site, thus facilitating electron transfer, disrupting surface barrier energy, and promoting multi-exciton dissociations. Transient absorption spectroscopy showed enhanced charge transfer and reduced energy barriers, resulting in an impressive CO2-to-CO conversion rate of 132.8 µmol g-1 h-1 with 96.5% selectivity. The CPB-FCA catalyst exhibited four-cycle reusability and 72 h of long-term stability, marking a significant nine-fold improvement compared to pristine CPB (14.4 µmol g-1 h-1). These results provide insights into the influential role of FCA in regulating intramolecular charge transfer, enhancing multi-exciton dissociation, and improving CO2 photoreduction on CPB QDs. Furthermore, these findings offer valuable knowledge for controlling quantum-confined exciton dissociation to enhance CO2 photocatalysis.

Atomic observation and structural evolution of covalent organic framework rotamers.

Dynamic 3D covalent organic frameworks (COFs) have shown concerted structural transformation and adaptive gas adsorption due to the conformational diversity of organic linkers. However, the isolation and observation of COF rotamers constitute undergoing challenges due to their comparable free energy and subtle rotational energy barrier. Here, we report the atomic-level observation and structural evolution of COF rotamers by cryo-3D electron diffraction and synchrotron powder X-ray diffraction. Specifically, we optimize the crystallinity and morphology of COF-320 to manifest its coherent dynamic responses upon adaptive inclusion of guest molecules. We observe a significant crystal expansion of 29 vol% upon hydration and a giant swelling with volume change up to 78 vol% upon solvation. We record the structural evolution from a non-porous contracted phase to two narrow-pore intermediate phases and the fully opened expanded phase using n-butane as a stabilizing probe at ambient conditions. We uncover the rotational freedom of biphenylene giving rise to significant conformational changes on the diimine motifs from synclinal to syn-periplanar and anticlinal rotamers. We illustrate the 10-fold increment of pore volumes and 100% enhancement of methane uptake capacity of COF-320 at 100 bar and 298 K. The present findings shed light on the design of smarter organic porous materials to maximize host-guest interaction and boost gas uptake capacity through progressive structural transformation.

Self-Driven Electric Field Control of Orbital Electrons in AuPd Alloy Nanoparticles for Cancer Catalytic Therapy.

The free radical generation efficiency of nanozymes in cancer therapy is crucial, but current methods fall short. Alloy nanoparticles (ANs) hold promise for improving catalytic performance due to their inherent electronic effect, but there are limited ways to modulate this effect. Here, a self-driven electric field (E) system utilizing triboelectric nanogenerator (TENG) and AuPd ANs with glucose oxidase (GOx)-like, catalase (CAT)-like, and peroxidase (POD)-like activities is presented to enhance the treatment of 4T1 breast cancer in mice. The E stimulation from TENG enhances the orbital electrons of AuPd ANs, resulting in increased CAT-like, GOx-like, and POD-like activities. Meanwhile, the catalytic cascade reaction of AuPd ANs is further amplified after catalyzing the production of H2 O2 from the GOx-like activities. This leads to 89.5% tumor inhibition after treatment. The self-driven E strategy offers a new way to enhance electronic effects and improve cascade catalytic therapeutic performance of AuPd ANs in cancer therapy.

A Pt1Pd Single-Atom Alloy Nanozyme with Boosted Enzyme-Like Activity for Efficient Photo-Mediated Tumor Therapy.

Single-atom nanozymes (SAzymes) are emerging natural enzyme mimics and have attracted much attention in the biomedical field. SAzymes with Metal─Nx sites designed on carbon matrixes are currently the mainstream in research. It is of great significance to further expand the types of SAzymes to enrich the nanozyme library. Single-atom alloys (SAAs) are a material in which single-atom metal sites are dispersed onto another active metal matrix, and currently, there is limited research on their enzyme-like catalytic performance. In this work, a biodegradable Pt1Pd SAA is fabricated via a simple galvanic replacement strategy, and for the first time reveals its intrinsic enzyme-like catalytic performance including catalase-, oxidase-, and peroxidase-like activities, as well as its photodynamic effect. Experimental characterizations demonstrate that the introduction of single-atom Pt sites contributes to enhancing the affinity of Pt1Pd single-atom alloy nanozyme (SAAzyme) toward substrates, thus exhibiting boosted catalytic efficiency. In vitro and in vivo experiments demonstrate that Pt1Pd SAAzyme exhibits a photo-controlled therapeutic effect, with a tumor inhibition rate of up to 100%. This work provides vital guidance for opening the research direction of SAAs in enzyme-like catalysis.

Zinc-Based ROS Amplifiers Trigger Cancer Chemodynamic/Ion Interference Therapy Through Self-Cascade Catalysis.

Nanozyme-mediated chemodynamic therapy has emerged as a promising strategy due to its tumor specificity and controlled catalytic activity. However, the poor efficacy caused by low hydrogen peroxide (H2O2) levels in the tumor microenvironment (TME) poses challenges. Herein, an H2O2 self-supplying nanozyme is constructed through loading peroxide-like active platinum nanoparticles (Pt NPs) on zinc peroxide (ZnO2) (denoted as ZnO2@Pt). ZnO2 releases H2O2 in response to the acidic TME. Pt NPs catalyze the hydroxyl radical generation from H2O2 while reducing the mitigation of oxidative stress by glutathione, serving as a reactive oxygen (ROS) amplifier through self-cascade catalysis. In addition, Zn2+ released from ZnO2 interferes with tumor cell energy supply and metabolism, enabling ion interference therapy to synergize with chemodynamic therapy. In vitro studies demonstrate that ZnO2@Pt induces cellular oxidative stress injury through enhanced ROS generation and Zn2+ release, downregulating ATP and NAD+ levels. In vivo assessment of anticancer effects showed that ZnO2@Pt could generate ROS at tumor sites to induce apoptosis and downregulate energy supply pathways associated with glycolysis, resulting in an 89.7% reduction in tumor cell growth. This study presents a TME-responsive nanozyme capable of H2O2 self-supply and ion interference therapy, providing a paradigm for tumor-specific nanozyme design.

The strengthened impact of water availability at interannual and decadal time scales on vegetation GPP.

Water availability (WA) is a key factor influencing the carbon cycle of terrestrial ecosystems under climate warming, but its effects on gross primary production (EWA-GPP ) at multiple time scales are poorly understood. We used ensemble empirical mode decomposition (EEMD) and partial correlation analysis to assess the WA-GPP relationship (RWA-GPP ) at different time scales, and geographically weighted regression (GWR) to analyze their temporal dynamics from 1982 to 2018 with multiple GPP datasets, including near-infrared radiance of vegetation GPP, FLUXCOM GPP, and eddy covariance-light-use efficiency GPP. We found that the 3- and 7-year time scales dominated global WA variability (61.18% and 11.95%), followed by the 17- and 40-year time scales (7.28% and 8.23%). The long-term trend also influenced 10.83% of the regions, mainly in humid areas. We found consistent spatiotemporal patterns of the EWA-GPP and RWA-GPP with different source products: In high-latitude regions, RWA-GPP changed from negative to positive as the time scale increased, while the opposite occurred in mid-low latitudes. Forests had weak RWA-GPP at all time scales, shrublands showed negative RWA-GPP at long time scales, and grassland (GL) showed a positive RWA-GPP at short time scales. Globally, the EWA-GPP , whether positive or negative, enhanced significantly at 3-, 7-, and 17-year time scales. For arid and humid zones, the semi-arid and sub-humid zones experienced a faster increase in the positive EWA-GPP , whereas the humid zones experienced a faster increase in the negative EWA-GPP . At the ecosystem types, the positive EWA-GPP at a 3-year time scale increased faster in GL, deciduous broadleaf forest, and savanna (SA), whereas the negative EWA-GPP at other time scales increased faster in evergreen needleleaf forest, woody savannas, and SA. Our study reveals the complex and dynamic EWA-GPP at multiple time scales, which provides a new perspective for understanding the responses of terrestrial ecosystems to climate change.

Frizzled receptors (FZDs) in Wnt signaling: potential therapeutic targets for human cancers.

Frizzled receptors (FZDs) are key contributors intrinsic to the Wnt signaling pathway, activation of FZDs triggering the Wnt signaling cascade is frequently observed in human tumors and intimately associated with an aggressive carcinoma phenotype. It has been shown that the abnormal expression of FZD receptors contributes to the manifestation of malignant characteristics in human tumors such as enhanced cell proliferation, metastasis, chemotherapy resistance as well as the acquisition of cancer stemness. Given the essential roles of FZD receptors in the Wnt signaling in human tumors, this review aims to consolidate the prevailing knowledge on the specific status of FZD receptors (FZD1-10) and elucidate their respective functions in tumor progression. Furthermore, we delineate the structural basis for binding of FZD and its co-receptors to Wnt, and provide a better theoretical foundation for subsequent studies on related mechanisms. Finally, we describe the existing biological classes of small molecule-based FZD inhibitors in detail in the hope that they can provide useful assistance for design and development of novel drug candidates targeted FZDs.

DNA Assembly of Plasmonic Nanostructures Enables In Vivo SERS-Based MicroRNA Detection and Tumor Photoacoustic Imaging.

Controllable self-assembly of the DNA-linked gold nanoparticle (AuNP) architecture for in vivo biomedical applications remains a key challenge. Here, we describe the use of the programmed DNA tetrahedral structure to control the assembly of three different types of AuNPs (∼20, 10, and 5 nm) by organizing them into defined positioning and arrangement. A DNA-assembled "core-satellite" architecture is built by DNA sequencing where satellite AuNPs (10 and 5 nm) surround a central core AuNP (20 nm). The density and arrangement of the AuNP satellites around the core AuNP were controlled by tuning the size and amount of the DNA tetrahedron functionalized on the core AuNPs, resulting in strong electromagnetic field enhancement derived from hybridized plasmonic coupling effects. By conjugating with the Raman molecule, strong surface-enhanced Raman scattering photoacoustic imaging signals could be generated, which were able to image microRNA-21 and tumor tissues in vivo. These results provided an efficient strategy to build precision plasmonic superstructures in plasmonic-based bioanalysis and imaging.

Nanozyme-Based Colorimetric SARS-CoV-2 Nucleic Acid Detection by Naked Eye.

Fluorescence-based PCR and other amplification methods have been used for SARS-CoV-2 diagnostics, however, it requires costly fluorescence detectors and probes limiting deploying large-scale screening. Here, a cut-price colorimetric method for SARS-CoV-2 RNA detection by iron manganese silicate nanozyme (IMSN) is established. IMSN catalyzes the oxidation of chromogenic substrates by its peroxidase (POD)-like activity, which is effectively inhibited by pyrophosphate ions (PPi). Due to the large number of PPi generated by amplification processes, SARS-CoV-2 RNA can be detected by a colorimetric readout visible to the naked eye, with the detection limit of 240 copies mL-1 . This conceptually new method has been successfully applied to correctly distinguish positive and negative oropharyngeal swab samples of COVID-19. Colorimetric assay provides a low-cost and instrumental-free solution for nucleic acid detection, which holds great potential for facilitating virus surveillance.

Biomimetic Nanobomb for Synergistic Therapy with Inhibition of Cancer Stem Cells.

Cancer stem cells (CSCs), a type of cell with self-renewal, unlimited proliferation, and insensitivity to common physical and chemical factors, are the key to cancer metastasis, recurrence, and chemo-resistance. Available CSCs inhibition strategies are mainly based on small molecule drugs, yet are limited by their off-target toxicity. The link between CSCs and non-CSCs interconversion is difficult to sever. In this work, a nanotherapeutic strategy based on MnOx -loaded polydopamine (MnOx /PDA) nanobombs with chemodynamic, photodynamic, photothermal and biodegradation properties to inhibit CSCs and non-CSCs concurrently is reported. The MnOx /PDA nanobombs can directly disrupt the microenvironment and tumorigenic capacity of CSCs by generating hyperthermia, oxidative stress and alleviating hypoxia. The markers of CSCs are subsequently downregulated, leading to the clearance of CSCs. Meanwhile, the synergistic therapy mediated by MnOx /PDA nanobombs can directly ablate the bulk tumor cells, thus cutting off the supply of CSCs transformation. For tumor targeting, MnOx /PDA is coated with macrophage membrane. The final tumor inhibition rate of the synergistic therapy is 70.8% in colorectal cancer (CRC) model. Taken together, the present work may open up the exploration of nanomaterial-based synergistic therapy for the simultaneous elimination of therapeutically resistant CSCs and non-CSCs.

The risk factors of thrombus formation and the effect of catheter ablation on repetitive thrombus formation in patients with atrial fibrillation: a single center retrospective study in China.

BACKGROUND: Atrial fibrillation (AF) predisposes patients to the formation of atrial thrombi. The CHA2DS2-VASc score does not include all risk factors for atrial thrombosis. The present study is designed to explore the influencing factors of thrombus formation in patients with AF and to investigate the effect of catheter ablation (CA) on recurrent thrombosis in patients with a history of intracardiac thrombus. METHODS: (1) This study consisted of 1726 patients that underwent CA, among which 58 patients had a history of intracardiac thrombus prior to CA. The risk factors for thrombus formation were explored by comparing the baseline clinical characteristics of patients with and without atrial thrombus. (2) The left atrial appendage flow velocity (LAAFV) in patients with a history of intracardiac thrombus who were willing to undergo transesophageal echocardiography (TEE) at the latest follow-up were examined, and comparisons of the LAAFV was made before and after CA. RESULTS: The median follow-up period is 13 months. Persistent AF was found to be the only independent risk factor affecting the formation of atrial thrombus among the investigated factors (OR 3.152; 95%CI 1.806-5.500; p < 0.001). Twenty-seven patients agreed to undergo TEE during follow-up, no clinical ischemic stroke events were recorded, no recurrent intracardiac thrombus formation was detected in patients, 15 patients maintained sinus rhythm (55.6%) during follow-up; successful CA significantly increased LAAFV (difference between latest evaluation prior to CA 17.46 ± 14.81 cm/s, p < 0.001). CONCLUSIONS: Persistent AF is the only independent risk factor for thrombus formation. Successful CA may improve the LAAFV and thereby decrease the risk of intracardiac thrombus formation.

Pharyngeal Cavity Electrical Stimulation-Assisted Swallowing for Post-stroke Dysphagia: A Systematic Review and Meta-analysis of Randomized Controlled Studies.

Stroke is the leading cause of death and disability among adults. The incidence of stroke per 100, 000 patient-years was 2875. As many as 37% to 78% of patients with acute strokes suffer dysphagia. Dysphagia can easily lead to inhalation pneumonia, dehydration, malnutrition, and other serious complications, affecting the quality of life of stroke patients and increasing their mortality. Effective prevention and treatment of post-stroke dysphagia are of great significance to improving the prognosis and quality of life of patients. Some studies have shown that Pharyngeal cavity electrical stimulation-assisted swallowing (PCES-assisted swallowing) has a positive effect on patients with post-stroke dysphagia. This study will evaluate the effects of PCES-assisted swallowing on post-stroke dysphagia, including swallowing function, withdrawal rate of nasal feeding tubes, duration of hospitalization, and so on. Randomized controlled trials (RCTs) of PCES-assisted swallowing in the treatment of post-stroke dysphagia were searched in eight databases, including Cochrane Library, Embase, PubMed, Web of Science, Chinese Biomedical Literature Database, VIP Information Resource System, CNKI, and Wanfang Medical Science. The retrieval time was from the database establishment to June 2022. Rayyan was used to screen the retrieved literature risk of bias for included studies and was calculated using ROB2.0. The RevMan 5.3 software was used for the meta-analysis with the standard mean difference (SMD) and 95% confidence interval (CI). The model type was a random effect model, The risk ratio (RR) was used as the effect size for the two categorical variables. The swallowing function scores, withdrawal rate of nasal feeding tubes, and Length of stay (LOS) of the intervention and control groups were extracted, and the results of the meta-analysis were presented using a forest plot. Six studies from 2010 to 2018 with a total of 341 people were included in the meta-analysis. All studies reported quantitative outcome measures for the severity of dysphagia, and some reported the withdrawal rate of nasal feeding tubes, LOS, and penetration-aspiration-scale (PAS). The overall swallowing function of the PCES group was better than that of the control group (SMD = - 0.20, 95%CI - 0.38 to - 0.03, P = 0.02). In terms of the severity of dysphagia, there was a statistically significant difference in the Dysphagia Severity Rating scale (DSRS) between the Pharyngeal cavity electrical stimulation (PCES) group and the control group (SMD = - 0.24, 95%CI - 0.48 to 0, P = 0.05). The PCES group nasal feeding withdrawal rate of nasal feeding tubes was higher than the control group (RR = 2.88, 95% CI 1.15 to 7.26, P = 0.02). There was no significant difference in the LOS between the PCES group and the control group (SMD = - 0.19, 95%CI - 0.44 to 0.07, P = 0.15). This systematic review and meta-analysis provide reasonably reliable evidence that PCES-assisted swallowing can improve nasogastric feeding swallowing function and the withdrawal rate of nasal feeding tubes in patients with post-stroke dysphagia. However, the evidence for reducing oral feeding, aspiration, and length of hospitalization stay is lacking, and further studies are needed.

The Effect of Repetitive Transcranial Magnetic Stimulation in Synchronization with Effortful Swallowing on Post-stroke Dysphagia.

Either effortful swallowing exercise or repetitive transcranial magnetic stimulation (rTMS) is considered as an effective method to treat dysphagia after stroke. Thus, synchronizing these two interventions may improve the efficiency of treatment. This trial intended to explore the effects of rTMS and effortful swallowing exercise on the recovery of swallowing function in patients after stroke. A total of 56 patients with post-stroke dysphagia who were able to actively cooperate with the training were analyzed in this study. We experimented with different intervention effects of rTMS synchronization with effortful swallowing training (group 1), rTMS (group 2), and traditional swallowing training alone (group 3). Every patient completed conventional swallowing training 5 days a week for 2 weeks. Patients in group 1 and group 2 underwent 10 consecutive sessions of 5 Hz rTMS over the affected mylohyoid cortical region. Fiberoptic endoscopic dysphagia severity scale (FEDSS), penetration/aspiration scale (PAS), standardized swallowing assessment (SSA), and functional oral intake scale (FOIS) were assessed and compared across the groups. No significant difference in FEDSS, PAS, SSA, or FOIS scores was found at baseline among the three groups. The mean change values of the FEDSS score, PAS score, SSA score, and FOIS score between baseline and post-intervention of the three groups (H = 16.05, P < 0.001; H = 21.70, P < 0.001; F (2, 53) = 9.68, P < 0.001; H = 18.26, P < 0.001; respectively) were statistically significant. In addition, the mean change values of FEDSS, PAS, SSA, and FOIS scores in participants in group 1 (all P < 0.001) and group 2 (P = 0.046; P = 0.045; P = 0.028; P = 0.032; respectively) were significantly higher than in group 3. Similarly, the mean change values of FEDSS, PAS, SSA, and FOIS scores were significantly higher in participants in group 1 than in group 2 (P = 0.046; P = 0.038; P = 0.042; P = 0.044; respectively). The results revealed that the conjunction of rTMS and effortful swallowing training was an effective method to facilitate the recovery of swallowing function in stroke patients. The present clinical trial provided a new treatment method for the functional restoration of swallowing in stroke patients, which may further facilitate the recovery of swallowing function in stroke patients with swallowing disorders.

Prophylactic dexmedetomidine use did not decrease the incidence of delirium in patients undergoing cardiac surgery: A meta-analysis.

OBJECTIVE: The benefits of prophylactic dexmedetomidine use in patients undergoing cardiac surgery remain controversial. The aim of this meta-analysis was to investigate the short-term clinical outcomes of dexmedetomidine use versus non-dexmedetomidine use. METHODS: Systematic searches using PubMed, Embase, and the Cochrane Library were carried out for English articles published from inception to 23 September 2021. This was followed by a meta-analysis investigating delirium, the length of delirium, mortality, bradycardia, hypotension, the length of intensive care unit (ICU) and hospital stay, and the duration of mechanical ventilation. RESULTS: Ten randomized controlled trials (RCTs) totaling 2550 patients were included. In the dexmedetomidine group incidence of delirium was 13.5%, compared with 16.1% in the control group. The risk ratio (RR) for the comparison was 0.69 (95% CI, 0.47 - 1.00; p = .052). In addition, there were no differences in mortality (RR, 0.56; 95% CI, 0.27 - 1.14; p = .109), the incidence of bradycardia (RR, 1.20; 95% CI, 0.91 - 1.57; p = .201), the incidence of hypotension (RR, 0.90; 95% CI, 0.57 - 1.44; p = .674), and the length of delirium mean difference (MD, -0.99; 95% CI, -2.20 to 0.21; p = .106). However, prophylactic dexmedetomidine use significantly reduced the duration of mechanical ventilation (MD, -2.03; 95% CI, -3.35 to -0.70; p = .003), length of ICU stay (MD, -3.17; 95% CI, -5.10 to -1.24; p = .001), and length of hospital stay (MD, -1.76; 95% CI, -2.88 to -0.66; p = .002). CONCLUSIONS: Prophylactic dexmedetomidine use did not decrease the incidence of delirium in patients undergoing cardiac surgery, but significantly reduced the duration of mechanical ventilation, length of ICU stay, and length of hospital stay.

Molecular Dynamics Study of the Effect of Charge and Glycosyl on Superoxide Anion Distribution near Lipid Membrane.

To examine the effects of membrane charge, the electrolyte species and glycosyl on the distribution of negatively charged radical of superoxide anion (·O2-) around the cell membrane, different phospholipid bilayer systems containing ·O2- radicals, different electrolytes and phospholipid bilayers were constructed through Charmm-GUI and Amber16. These systems were equilibrated with molecular dynamics by using Gromacs 5.0.2 to analyze the statistical behaviors of ·O2- near the lipid membrane under different conditions. It was found that in the presence of potassium rather than sodium, the negative charge of the phospholipid membrane is more likely to rarefy the superoxide anion distribution near the membrane surface. Further, the presence of glycosyl significantly reduced the density of ·O2- near the phospholipid bilayer by 78.3% compared with that of the neutral lipid membrane, which may have a significant contribution to reducing the lipid peroxidation from decreasing the ·O2- density near the membrane.

Preparation and Characterization of a Photo-Crosslinked Methacryloyl-Collagen Composite Film to Promote Corneal Nerve Regeneration via Surface Grafting of Taurine Molecules.

Blindness is frequently caused by corneal abnormalities, and corneal transplantation is the most effective treatment method. It is extremely important to develop high-quality artificial corneas because there are not enough donor corneas accessible for cornea transplantation. One of the most-often utilized materials is collagen, which is the primary component of natural cornea. Collagen-based corneal repair materials have good physicochemical properties and excellent biocompatibility, but how to promote the regeneration of the corneal nerve after keratoplasty is still a big challenge. In this research, in order to promote the growth of nerve cells on a collagen (Col) substrate, a novel collagen-based material was synthesized starting from the functionalization of collagen with unsaturated methacryloyl groups that three-dimensionally photopolymerize to a 3D network of chemically crosslinked collagen (ColMA), onto which taurine molecules were eventually grafted (ColMA-Tr). The physicochemical properties and biocompatibility of the Col, ColMA and ColMA-Tr films were evaluated. By analyzing the results, we found that all the three samples had good moisture retention and aq high covalent attachment of methacryloyl groups followed by their photopolymerization improved the mechanical properties of the ColMA and ColMA-Tr. Most importantly, compared with ColMA, the taurine-modified collagen-MA film significantly promoted the growth of nerve cells and corneal epithelial cells on its surface. Our preliminary results suggest that this novel ColMA-Tr film may have potential use in cornea tissue engineering in the future.

Nano-enabled Quenching of Bacterial Communications for the Prevention of Biofilm Formation.

Biofilm formation is a major threat to industry, the environment and human health. While killing of embedded microbes in biofilms may inevitably lead to the evolution of antimicrobial resistance (AMR), catalytic quenching of bacterial communications by lactonase is a promising antifouling approach. Given the shortcomings of protein enzymes, it is attractive to engineer synthetic materials to mimic the activity of lactonase. Herein, an efficient lactonase-like Zn-Nx -C nanomaterial was synthesized by tuning the coordination environment around zinc atoms to mimic the active domain of lactonase for catalytical interception of bacterial communications in biofilm formation. The Zn-Nx -C material could selectively catalyze 77.5 % hydrolysis of N-acylated-L-homoserine lactone (AHL), a critical bacterial quorum sensing (QS) signal in biofilm construction. Consequently, AHL degradation downregulated the expression of QS-related genes in antibiotic resistant bacteria and significantly prevented biofilm formation. As a proof of concept, Zn-Nx -C-coated iron plates prevented 80.3 % biofouling after a month exposure in river. Overall, our study provides a nano-enabled contactless antifouling insight to avoid AMR evolution by engineering nanomaterials for mimicking the key bacterial enzymes (e.g., lactonase) functioning in biofilm construction.

DNA Logic Circuits for Cancer Theranostics.

Cancer diagnosis and therapeutics (theranostics) based on the tumor microenvironment (TME) and biomarkers has been an emerging approach for precision medicine. DNA nanotechnology dynamically controls the self-assembly of DNA molecules at the nanometer scale to construct intelligent DNA chemical reaction systems. The DNA logic circuit is a particularly emerging approach for computing within the DNA chemical systems. DNA logic circuits can sensitively respond to tumor-specific markers and the TME through logic operations and signal amplification, to generate detectable signals or to release anti-cancer agents. In this review, the fundamental concepts of DNA logic circuits are clarified, the basic modules in the circuit are summarized, and how this advanced nano-assembly circuit responds to tumor-related molecules, how to perform logic operations, to realize signal amplification, and selectively release drugs through discussing over 30 application examples, are demonstrated. This review shows that DNA logic circuits have powerful logic judgment and signal amplification functions in improving the specificity and sensitivity of cancer diagnosis and making cancer treatment controllable. In the future, researchers are expected to overcome the existing shortcomings of DNA logic circuits and design smarter DNA devices with better biocompatibility and stability, which will further promote the development of cancer theranostics.

Molecular Imaging-Guided Sonodynamic Therapy.

Low-intensity ultrasound-triggered sonodynamic therapy (SDT) is a promising noninvasive therapeutic modality due to its strong tissue penetration ability. In recent years, with the development of nanotechnology, nanoparticle-based sonosensitizer-mediated SDT has been widely investigated. With the increasing demand for precise and personalized treatment, abundant novel sonosensitizers with imaging capabilities have been developed for determining the optimal therapeutic window, thus significantly enhancing treatment efficacy. In this review, we focus on the molecular imaging-guided SDT. The prevalent mechanisms of SDT are discussed, including ultrasonic cavitation, sonoluminescence, reactive oxygen species, and mechanical damage. In addition, we introduce the major molecular imaging techniques and the design principles based on nanoparticles to achieve efficient imaging. Furthermore, the imaging-guided SDT for the treatment of cancer, bacterial infections, and vascular diseases is summarized. The ultimate goal is to design more effective imaging-guided SDT modalities and provide novel ideas for clinical translation of SDT.

Circular RNA Calm4 Regulates Hypoxia-Induced Pulmonary Arterial Smooth Muscle Cells Pyroptosis via the Circ-Calm4/miR-124-3p/PDCD6 Axis.

[Figure: see text].