Publications by authors named "Chenfeng Xu"

Article Synopsis
  • * The study introduces WZ-AChE, a two-photon excited fluorescent probe designed to detect AChE activity with high sensitivity and selectivity, overcoming limitations of current detection methods.
  • * WZ-AChE was successfully used in models of Parkinson's disease and depression, showing increased AChE activity compared to controls, thereby aiding research into the mechanisms of these diseases.
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With the emergence of numerous food safety problems, rapid and accurate detection of histamine in food spoilage remains a challenge. To this end, we developed a simple design and easy synthesis of fluorescein-based probe FCHO to achieve specific and rapid (<1 s) quantitative detection of histamine through "imine formation" reaction. Significant enhanced fluorescence signal in response to histamine enabled our probe with high sensitivity as low as 51 nM.

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Objectives: To evaluate the therapeutic regimen, efficacy and safety of intrathecal or intraventricular (ITH/IVT) administration of polymyxin B for hospital-acquired central nervous system (CNS) infections caused by carbapenem-resistant Acinetobacter baumannii (CRAB).

Methods: A retrospective study was undertaken of patients with CNS infections caused by CRAB treated with ITH/IVT combination therapy. The primary outcome was the clinical efficacy of treatment.

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Nitroreductase (NTR) is widely regarded as a biomarker whose enzymatic activity correlates with the degree of hypoxia in solid malignant tumors. Herein, we utilized 2-dimethylamino-7-hydroxynaphthalene as fluorophore linked diverse nitroaromatic groups to obtain four NTR-activatable two-photon fluorescent probes based on covalent assembly strategy. With the help of computer docking simulation and in vitro assay, the sulfonate-based probe XN3 was proved to be able to identify NTR activity with best performances in rapid response, outstanding specificity, and sensitivity in comparison with the other three probes.

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Immunosuppressive microenvironment and poor immunogenicity are two stumbling blocks in anti-tumor immune activation. Tumor associated macrophages (TAMs) play crucial roles in immunosuppressive microenvironment, while immunogenic cell death (ICD) is a typical strategy to boost immunogenicity. Herein, we developed a coordinative modular assembly-based self-reinforced nanoparticle, (CaO/TA)-(Fe/BSA) which integrated CaO, Fe-tannic acid coordinated networks and albumin under the instruction of molecular dynamics simulation.

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The physical characteristics of chyme during gastrointestinal digestion are considered to significantly affect nutrient digestion and absorption (such as glucose diffusion), which has an impact on postprandial satiety. The present study aims to analyze the hydration rate (HR) and rheological properties of deacetylated konjac glucomannan (DKGM) at different degrees and then explore their effects on rice texture, digestive properties, and the subjects' post-meal appetite. The present results show that, as the deacetylation degree (DD) of KGM increased, the intersection point of the viscoelastic modulus shifted to a high shear rate frequency, and as the swelling time of the DKGM was prolonged, its HR decreased significantly.

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Colorectum cancer has become one of the most fatal cancer diseases, in which NAD(P)H: quinone oxidoreductase 1 (NQO1) plays a role in intracellular free radical reduction and detoxification and has been linked to colorectum cancer and chemotherapy resistance. Therefore, rational design of optical probe for NQO1 detection is urgent for the early diagnosis of colorectum cancer. Herein, we have developed a novel two-photon fluorescent probe, WHFD, which is capable of selectively detecting of intracellular NQO1 with two-photon (TP) absorption (800 nm) and near-infrared emission (620 nm).

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Bacterial infections would cause pathological inflammation and even generate chronic wound. Herein, a ciprofloxacin (Cip)-loaded mild acid-responsive electrospinning nanofiber membrane (NFM) containing 3-diethylaminopropyl isothiocyanate material grafted glycol chitosan (GC-DEAP) was fabricated to prevent bacterial infection against hemostatic and inflammatory phases of wounds. The presence of Cip and GC-DEAP in the objective NFM (PCL/GC-DEAP/Cip) was confirmed through XRD and FTIR.

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The simultaneous extraction of crocin and geniposide from gardenia fruits (Gardenia jasminoides Ellis) was performed by integrating natural deep eutectic solvents (NADES) and ultrasound-assisted extraction (UAE). Among the eight kinds of NADES screened, choline chloride-1,2-propylene glycol was the most suitable extractant. The probe-type ultrasound-assisted NADES extraction system (pr-UAE-NADES) demonstrated higher extraction efficiency compared with plate-type ultrasound-assisted NADES extraction system (pl-UAE-NADES).

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The selenization of natural products refers to the chemical modification method of artificially introducing selenium atoms into natural products to interact with the functional groups in the target molecule to form selenides. Nowadays, even though scientists in fields involving organic selenium compounds have achieved numerous results due to their continuous investment, few comprehensive and systematic summaries relating to their research results can be found. The present paper summarizes the selenization modification methods of several kinds of important natural products, such as polysaccharides, proteins/polypeptides, polyphenols, lipids, and cyclic compounds, as well as the basic principles or mechanisms of the selenizing methods.

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Objectives: This retrospective study aimed to identify the effectiveness of ceftazidime/avibactam (CAZ/AVI) and its optimisation programs for severe hospital-acquired pulmonary infections (sHAPi) caused by carbapenem-resistant and difficult-to-treat Pseudomonas aeruginosa (CRPA and DTR-P. aeruginosa).

Methods: We retrospectively analysed observational data on treatment and outcomes of CAZ/AVI for sHAPi caused by CRPA or DTR-P.

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Object detection serves as one of most fundamental computer vision tasks. Existing works on object detection heavily rely on dense object candidates, such as k anchor boxes pre-defined on all grids of an image feature map of size H×W. In this paper, we present Sparse R-CNN, a very simple and sparse method for object detection in images.

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Dietary fiber has been widely used in designing foods with a high satiating capacity, as the use of satiety-enhancing food is considered to be a promising strategy for combating obesity and the overweight condition. In the present study, partially degraded konjac glucomannan (DKGM) diets with different water-holding capacities, swelling capacities, and viscosities were used to feed rats to investigate the effects of the fiber's physical properties in regulating the appetite response of the animals. The results showed that the mass and water content of the gastrointestinal chyme increased as the diet's physical properties were enhanced by the DKGM, which increased the stomach distention of the rats and promoted satiation.

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Blocking the programmed death-ligand 1 (PD-L1) on tumor cells with monoclonal antibody therapy has emerged as powerful weapon in cancer immunotherapy. However, only a minority of patients presented immune responses in clinical trials. To develop an alternative treatment method based on immune checkpoint blockade, we designed a novel and efficient CRISPR-Cas9 genome editing system delivered by cationic copolymer aPBAE to downregulate PD-L1 expression on tumor cells specifically knocking out Cyclin-dependent kinase 5 () gene .

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A simple, sensitive, and stable high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed and validated for the simultaneous determination of leucovorin and 5-methyltetrahydrofolate diastereomers in human plasma using methotrexate as the internal standard. The analytes and the internal standard were extracted from plasma samples by simple ultrafiltration centrifugation-based extraction. The separation was achieved on a chiral HSA column (150 mm×4 mm, 5 μm) using mobile phases containing 10 mmol pH 8.

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An intravenously administered drug delivery system should undergo a five-step 'CAPIR' cascade (circulation, accumulation, penetration, internalization and release), and the maximal efficiency of each step is of great importance to obtain the improved final therapeutic benefits and overall survival rate. Here, a pH/matrix metalloproteinase-9 (MMP9) sequentially responsive and continuously structure-transformable nanoparticle assembled from a doxorubicin (DOX)-conjugated peptide was exploited for comprehensively improving the 'CAPIR cascade' and eventually enhancing the therapeutic efficacy. The chimeric peptide can self-assemble into spherical nanoparticles (RGD-sNPs) at pH 7.

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A dual-sensitive nanoparticle delivery system was constructed by incorporating an acid sensitive hydrazone linker into thermosensitive nanoparticles (TSNs) for co-encapsulating doxorubicin (DOX) and interferon γ (IFNγ) and to realize the co-delivery of chemotherapy and immunotherapy agents against melanoma. DOX, a chemotherapeutic drug, was conjugated to TSNs by a pH-sensitive chemical bond, and IFNγ, a potent immune-modulator, was absorbed into TSNs through the thermosensitivity and electrostatics of nanoparticles. Consequently, the dual sensitive drug-loaded TSN delivery systems were successfully built and showed an obvious core-shell structure, good encapsulation efficiency of drugs, sustained and sensitive drug release, prolonged circulation time, as well as excellent synergistic antitumor efficiency against B16F10 tumor bearing mice.

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Tumor heterogeneity is considered as one of main obstacles to limit the clinical application of stimuli-responsive nanocarriers. Multidrug resistance (MDR) is also a major challenge in cancer chemotherapy. Here, we developed a tumor redox heterogeneity-responsive prodrug with self-induced reactive oxygen species (ROS) amplification property for facilitating rapid drug release and overcoming MDR and lung metastasis.

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Multidrug resistance (MDR) remains as an obstacle for effective cancer treatment. Herein, we developed a novel and efficient nanomedicine by virtue of the carrier characters and MDR inhibition effects of β-cyclodextrin (β-CD) and d-α-tocopheryl polyethylene glycol succinate (TPGS). A series of star-shaped polymers CD-g-TPGS with different TPGS substitution degree were synthesized for doxorubicin (DOX) delivery, where β-CD was identified as a core and TPGS as branches.

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