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Cooperation of transition metal catalysis with photocatalysis is an emerging powerful approach to achieve coupling reactions for the synthesis of important chemicals. Owing to their facilely modulated structures and properties via reticular chemistry, photoactive covalent organic frameworks (COFs) arise quickly in building metallaphotocatalytic platforms targeting more efficient and sustainable protocol. In this Minireview, we summarize the recent advances in COFs‐based (integrated) platforms to forge carbon‐carbon/heteroatom (C, B, N, O, P, and S, etc.) bonds via a variety of cross‐coupling reactions driven by light, with focuses on the engineering of COFs' backbone, as well as the organization mode of COFs and metal site promoted catalytic performance. We also highlight the essential role of the underlying electron/energy processes in metallated COFs platforms (M@COFs). Aiming to guide catalysts' design to achieve more efficient performance or currently challenging transformations, we give our perspectives in this under‐developed yet promising field. [ABSTRACT FROM AUTHOR]

Prospects in light‐driven water activation have prompted rapid progress in hydrogenation reactions. We describe a Ni2+−N4 site built on carbon nitride for catalyzed semihydrogenation of alkynes, with water supplying protons, powered by visible‐light irradiation. Importantly, the photocatalytic approach developed here enabled access to diverse deuterated alkenes in D2O with excellent deuterium incorporation. Under visible‐light irradiation, evolution of a four‐coordinate Ni2+ species into a three‐coordinate Ni+ species was spectroscopically identified. In combination with theoretical calculations, the photo‐evolved Ni+ is posited as HO−Ni+−N2 with an uncoordinated, protonated pyridinic nitrogen, formed by coupled Ni2+ reduction and water dissociation. The paired Ni−N prompts hydrogen liberation from water, and it renders desorption of alkene preferred over further hydrogenation to alkane, ensuring excellent semihydrogenation selectivity. [ABSTRACT FROM AUTHOR]

Prospects in light‐driven water activation have prompted rapid progress in hydrogenation reactions. We describe a Ni2+−N4 site built on carbon nitride for catalyzed semihydrogenation of alkynes, with water supplying protons, powered by visible‐light irradiation. Importantly, the photocatalytic approach developed here enabled access to diverse deuterated alkenes in D2O with excellent deuterium incorporation. Under visible‐light irradiation, evolution of a four‐coordinate Ni2+ species into a three‐coordinate Ni+ species was spectroscopically identified. In combination with theoretical calculations, the photo‐evolved Ni+ is posited as HO−Ni+−N2 with an uncoordinated, protonated pyridinic nitrogen, formed by coupled Ni2+ reduction and water dissociation. The paired Ni−N prompts hydrogen liberation from water, and it renders desorption of alkene preferred over further hydrogenation to alkane, ensuring excellent semihydrogenation selectivity. [ABSTRACT FROM AUTHOR]

[Display omitted] • The molecular precursor of high affinity bicyclic peptide targeting Nectin4 was prepared and radiolabeled by 68Ga. • The novel Nectin4 molecular probe showed good tumor uptake and pharmacokinetic properties in vivo. • The Nectin4 tracer 68Ga-DN68 exhibits a high tumor-to-background ratio. The diagnosis and treatment of triple negative breast cancer (TNBC) are huge challenges due to the lack of identifiable molecular targets. The high expression of Nectin4 in a variety of tumors, including TNBC, is associated with the occurrence, invasion, progression and poor prognosis of tumors. Therefore, Nectin4 is an emerging biomarker for the diagnosis and treatment of TNBC. A PET imaging method to non-invasively quantify Nectin4 expression levels may aid in TNBC diagnosis and classification. In this study, a novel bicyclic peptide molecular probe [68Ga]Ga-DN68 was used to evaluate the expression of Nectin4 in tumors. The radiolabeling rate of [68Ga]Ga-DN68 was over 97 %, while maintaining more than 99 % radiochemical purity. In vitro experiments showed that [68Ga]Ga-DN68 could effectively target Nectin4 in tumor cells, and the cellular uptake of MC38-Nectin4 cells (Nectin4+) was significantly higher than that of MC38 cells (Nectin4-). Biodistribution and PET imaging studies consistently showed that [68Ga]Ga-DN68 was specifically accumulated in MC38-Nectin4 and MDA-MB-468 tumors, which was significantly higher than that of MC38. When co-injected with cold DN68, the specific accumulation could block the tumor uptake of MDA-MB-468. Notably, the signal-to-noise ratio at the tumor site gradually increased over time, reaching a peak at 1 h. These results strongly suggest that [68Ga]Ga-DN68 has broad application prospects as a PET tracer in TNBC imaging. [ABSTRACT FROM AUTHOR]

Organic halide transformation is of high importance for fine chemical synthesis and environmental remediation. Integrated photocatalytic platforms open up distinctive reaction pathway for carbon-halogen bond activation/reconstruction. Herein we reveal carbon nitride (CN)-ligated single atom nickel (Ni 1 /CN), with accumulated electron on the CN, paves Ni-mediated electron-proton transfer, enabling hydrodehalogenation, along with the catalytic carbon–oxygen (C–O) coupling. The preference for hydrodehalogenation positively correlates with density of electron on CN. EPR measurements suggest photo-generated NiI interacts with aryl halides, followed by electron transfer or reductive elimination to give different products. Further kinetic studies on hydrodehalogenation/C–O coupling show the reaction orders of 0.1/0.5 in aryl halide and 1.5/0.03 in (CN) electron, unveiling rate-determining step as oxidative addition to NiI and (CN) electron transfer for the two conversions. Our work advances in modulating aryl halide conversion by carrier accumulation on the photoactive support and guides metallaphotocatalytic platform design/operation toward target transformations. [Display omitted] • Carbon nitride ligated single-site nickel is photo-activated to NiI with electrons accumulated on CN support, Ni 1 I/CN(n e). • In addition to C–O coupling via NiI/NiIII cycle, hydrodehalogenation occurs by Ni mediated (CN) electron-proton transfer. • Conversion path of aryl halide is regulated by density of electrons accumulated on CN. • Rate-determining steps are oxidative addition to NiI for coupling, and electron transfer for hydrodehalogenation. [ABSTRACT FROM AUTHOR]

• The one-step pretreatment is time-efficient, low-cost, and relatively environmental protection. • The method covered 17 categories of drugs with a wide range of log P values. • The method has little matrix effects and reasonable mass deviation. • The method has a high recovery rate and good linearity. • The method has high sensitivity and accuracy. To get rid of the singularity of the detection of veterinary drug residues in liquid milk, a high-throughput determination was developed for 126 VDRs in 17 categories in liquid milk based on the one-step extraction coupled with LC-HRMS (UPLC-Q-Exactive-Orbitrap-MS). The results showed that adding 2.5 mL of 0.1 mol/L Na2EDTA-McIlvaine in acetonitrile-methanol extractant (50:50, V/V) could effectively improve the response intensity of veterinary drug residues in liquid milk, reduce the matrix effect and eliminate the need for expensive SPE purification. The established external standard quantitative method has a LOD of 0.01–0.30 μg/L for all categories of veterinary drug residues, good linearity in the concentration range of LOQ of 0.03–1.00 μg/L, and correlation coefficients (r2) were all greater than 0.995. The spike recoveries at all three levels were between 80.30% and 119.95%. The positive detection rate of this method in 128 actual samples was 8.59%. [ABSTRACT FROM AUTHOR]

Image restoration is a common problem in visual process. In this paper, a modified minimization model is presented, which combines the L 1 and L 2 fidelity terms with a combined quadratic L 2 and TV regularizer just as the regularizer of Cai et al. (2013). The combined regularizer has the priorities of preserving desirable edges and ensuring several kinds of noises can be removed clearly. Split-Bregman algorithm is efficiently employed to solve this model and convergence analysis is also discussed. Moreover, we extend the proposed model and algorithm for image restoration involving blurry images and color images. Experimental results show that our proposed model and algorithm have good performance both in visual and ISNR values for different kinds of blurs and noises including mixed noise. [ABSTRACT FROM AUTHOR]

Immune checkpoint (IC) blockade therapy has become the first-line treatment for various cancers. However, the low response rate and acquired drug resistance severely restrict the clinical application of immune checkpoint inhibitors (ICIs). Nuclide molecular imaging of ICs can provide non-invasive and whole-body visualization of in vivo IC dynamic biodistribution. Therefore, molecular imaging of ICs can predict and monitor responses to ICIs as a complementary tool to existing immunohistochemical techniques. Herein, we outlined the current status and recent advances in molecular imaging of the "first-generation" and "next-generation" ICs in preclinical and clinical studies. [ABSTRACT FROM AUTHOR]

Semihydrogenation of alkynes represents one of the most viable route to produce functional alkene products. Herein we describe the visible-light-driven alcohol or water donating semihydrogenation catalyzed by nickel supported on carbon nitride scaffold (Ni/C 3 N 4) under ambient condition, exhibiting excellent alkene selectivity and broad substrate scope. The catalyst design takes advantage of C 3 N 4 to harvest visible irradiation and to tune the interaction of Ni with hydrogenation intermediates, which is essential for the excellent selectivity toward alkene products. The hydrogen atom incorporated in alkene products originates from hydroxyl group of methanol or water, via a Ni catalyzed proton reduction by photogenerated electrons to give the active surface hydrogen species (H*). Such hydrogenation pathway not only avoids harsh reaction condition but also enables facile synthesis of valuable deuterated alkenes using deuterated alcohols or D 2 O, promising enormous application potential for well-designed catalyst architectures in the light-driven selective transfer hydrogenation (deuteration) of alkynes and other organic substrates. [Display omitted] Visible-light-driven Semihydrogenation of Alkynes via Proton Reduction over Carbon Nitride supported Nickel • Ni/C 3 N 4 catalyzes highly selective semihydrogenation of alkynes under visible light irradiation using alcohol or water as the hydrogen source. • C 3 N 4 plays an important role in depressing overhydrogenation, ensuring high selectivity of alkenes. • Active hydrogen species produced by proton reduction engage in semihydrogenation. • This protocol allows facile synthesis of valuable deuterated alkenes using readily available deuterated alcohols or D 2 O. [ABSTRACT FROM AUTHOR]

Background: In our current work, an 18F-FDG PET/CT radiomics-based model was developed to assess the progression-free survival (PFS) and overall survival (OS) of patients with relapsed or refractory (R/R) diffuse large B-cell lymphoma (DLBCL) who received chimeric antigen receptor (CAR)-T cell therapy. Methods: A total of 61 DLBCL cases receiving 18F-FDG PET/CT before CAR-T cell infusion were included in the current analysis, and these patients were randomly assigned to a training cohort (n = 42) and a validation cohort (n = 19). Radiomic features from PET and CT images were obtained using LIFEx software, and radiomics signatures (R-signatures) were then constructed by choosing the optimal parameters according to their PFS and OS. Subsequently, the radiomics model and clinical model were constructed and validated. Results: The radiomics model that integrated R-signatures and clinical risk factors showed superior prognostic performance compared with the clinical models in terms of both PFS (C-index: 0.710 vs. 0.716; AUC: 0.776 vs. 0.712) and OS (C-index: 0.780 vs. 0.762; AUC: 0.828 vs. 0.728). For validation, the C-index of the two approaches was 0.640 vs. 0.619 and 0.676 vs. 0.699 for predicting PFS and OS, respectively. Moreover, the AUC was 0.886 vs. 0.635 and 0.778 vs. 0.705, respectively. The calibration curves indicated good agreement, and the decision curve analysis suggested that the net benefit of radiomics models was higher than that of clinical models. Conclusions: PET/CT-derived R-signature could be a potential prognostic biomarker for R/R DLBCL patients undergoing CAR-T cell therapy. Moreover, the risk stratification could be further enhanced when the PET/CT-derived R-signature was combined with clinical factors. [ABSTRACT FROM AUTHOR]

Immunochromatography testing strips (ICTs) promise to become the point-of-care test format for early diagnosis due to their convenience, low cost, and simplification. However, the insufficient signal intensity and limited sensitivity of this format hamper their application. Herein, we overcame these limitations by integrating rod-like ferric oxyhydroxide (β-FeOOH) nanoparticles with ICTs. By varying the concentration of PEI, a one-pot, mild-temperature hydrolysis method was adapted for the synthesis and morphology regulation of β-FeOOH nanorod. Due to the excellent enzyme-like catalytic activity toward peroxidase substrates (TMB) in the presence of hydrogen peroxide (H2O2), the β-FeOOH nanorod in ICTs served as a signal generator and the nanozyme for signal amplification. The proof-of-concept work was performed for the detection of human chorionic gonadotropin (hCG). A two fold improvement of detection sensitivity was achieved compared to the sensitivity of conventional Au NPs-based ICTs. These results show that β-FeOOH-based ICT has a potential application in POCT detection in clinical diagnostics. [ABSTRACT FROM AUTHOR]

The present work aimed to assemble a simple, portable and economical L-junction microfluidic device to realize the adjustment and tunability of homogeneous round-shaped particles synthesis. In this study, we synthesize two kind of microparticles, including magnetic alginate microparticles (MAM) and chitosan-coated magnetic alginate (CMAM) used for controlling the drug release under a mild condition. Comparing to the traditional method, the MAM synthesized via this microfluidic approach has uniform size distribution, adjustable diameter as well as tunable magnetism. By exploring the amoxicillin as model drug, the MAM displays excellent pH-sensitive release, the effect of particle size on the drug release rate was investigated as well. The results show the smaller particles (220 μm) show a faster release rate than the bigger materials (1000 μm) due to their larger specific area, providing more frequency to interact with the reaction solution. The positive polyelectrolyte, chitosan, coated on the magnetic alginate surface endows CMAM time extension in drug release by two times, successfully achieving drug controlled and sustained release via the kinetics analysis. In summary, this microfluidic approach provides a convenient and efficient fluidic design for the well-controlled synthesis of micro-and nanoscale particles, which is a potential choice used for controlled and sustained drug release. • A simple but efficient L-junction microfluidics for particulate materials synthesis • CMAM with uniform size, tunable diameter, magnetism and homogenous morphology • CMAM synthesized here fulfilled the controlled and sustained-release. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel radioactive tracer 68Ga-DOTA-PG1 derived from macrocyclic peptide BMS-71 was developed. • 68Ga-DOTA-PG1 showed high specificity and nanomolar affinity for PD-L1 imaging. • 68Ga-DOTA-PG1 provided clear visualization of PD-L1 + tumor (A375-hPD-L1) with high tumor-to-muscle. Programmed death-ligand 1 (PD-L1) serves as a crucial biomarker for guiding the screening of cancer patients and the stratification of immunotherapy. However, due to the high heterogeneity of tumors, the current gold standard for detecting PD-L1 expression (immunohistochemistry) fails to comprehensively evaluate the overall PD-L1 expression levels in the body. Fortunately, the use of PD-L1 targeted radiotracers enables quantitative, real-time, and noninvasive assessment of PD-L1 expression levels and dynamics in tumors. Notably, analyzing the binding mode between the precursor and the target protein to find linker binding sites that do not affect the activity of the target molecule can greatly enhance the successful development of molecular probes. This study introduced a groundbreaking cyclic peptide molecular probe called 68Ga-DOTA-PG1. It was derived from the BMS-71 cyclic peptide and was specifically designed to evaluate the expression of PD-L1 in tumors. The radiolabeling yield of 68Ga-DOTA-PG1 surpassed 97% while maintaining a radiochemical purity of over 99%. In vitro experiments demonstrated the effective targeting of PD-L1 in tumor cells by 68Ga-DOTA-PG1, with significantly higher cellular uptake observed in A375-hPD-L1 cells (PD-L1 +) compared to A375 cells (PD-L1-). Biodistribution and PET imaging studies consistently showed specific accumulation of 68Ga-DOTA-PG1 in A375-hPD-L1 tumors, with a maximum uptake of 11.06 ± 1.70% ID/g at 2 h, significantly higher than the tumor uptake in A375 cells (1.70 ± 0.17% ID/g). These results strongly indicated that 68Ga-DOTA-PG1 held great promise as a PET radiotracer for imaging PD-L1-positive tumors. [ABSTRACT FROM AUTHOR]

In the present work, dual-chamber microbial fuel cell ( MFC) was constructed, in which anaerobic sludge was used as the inoculum and potassium ferricyanide as the electron acceptor. We have investigated the untapped potential of carbon microspheres modified graphite anode ( CGA) fabricated by hydrothermal and calcinations method in the MFCs operation. The results showed that the CGA could be utilized as a novel and efficient MFC anode. The output power of the MFC involved with CGA is approximately 358 mW·m−2, which is 3.1 times of the counterpart MFC with graphite anode ( GA). Furthermore, this MFC showed a 68% chemical oxygen demand ( COD) removal rate of the wastewater. Through further analysis, the CGA could improve the specific surface area and enhance the adsorption of microorganism, which could efficiently favor the electron transfer rate between the microorganism and external circuit, resulting in the increase of the electrochemical activity of MFC. [ABSTRACT FROM AUTHOR]