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1.
Sci Bull (Beijing) ; 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39095273

ABSTRACT

Chemotherapy is the first-line treatment for cancer, but its systemic toxicity can be severe. Tumor-selective prodrug activation offers promising opportunities to reduce systemic toxicity. Here, we present a strategy for activating prodrugs using radiopharmaceuticals. This strategy enables the targeted release of chemotherapeutic agents due to the high tumor-targeting capability of radiopharmaceuticals. [18F]FDG (2-[18F]-fluoro-2-deoxy-D-glucose), one of the most widely used radiopharmaceuticals in clinics, can trigger Pt(IV) complex for controlled release of axial ligands in tumors, it might be mediated by hydrated electrons generated by water radiolysis resulting from the decay of radionuclide 18F. Its application offers the controlled release of fluorogenic probes and prodrugs in living cells and tumor-bearing mice. Of note, an OxaliPt(IV) linker is designed to construct an [18F]FDG-activated antibody-drug conjugate (Pt-ADC). Sequential injection of Pt-ADC and [18F]FDG efficiently releases the toxin in the tumor and remarkably suppresses the tumor growth. Radiotherapy is booming as a perturbing tool for prodrug activation, and we find that [18F]FDG is capable of deprotecting various radiotherapy-removable protecting groups (RPGs). Our results suggest that tumor-selective radiopharmaceutical may function as a trigger, for developing innovative prodrug activation strategies with enhanced tumor selectivity.

2.
World J Gastroenterol ; 30(29): 3511-3533, 2024 Aug 07.
Article in English | MEDLINE | ID: mdl-39156500

ABSTRACT

BACKGROUND: Calculus bovis (CB), used in traditional Chinese medicine, exhibits anti-tumor effects in various cancer models. It also constitutes an integral component of a compound formulation known as Pien Tze Huang, which is indicated for the treatment of liver cancer. However, its impact on the liver cancer tumor microenvironment, particularly on tumor-associated macrophages (TAMs), is not well understood. AIM: To elucidate the anti-liver cancer effect of CB by inhibiting M2-TAM polarization via Wnt/ß-catenin pathway modulation. METHODS: This study identified the active components of CB using UPLC-Q-TOF-MS, evaluated its anti-neoplastic effects in a nude mouse model, and elucidated the underlying mechanisms via network pharmacology, transcriptomics, and molecular docking. In vitro assays were used to investigate the effects of CB-containing serum on HepG2 cells and M2-TAMs, and Wnt pathway modulation was validated by real-time reverse transcriptase-polymerase chain reaction and Western blot analysis. RESULTS: This study identified 22 active components in CB, 11 of which were detected in the bloodstream. Preclinical investigations have demonstrated the ability of CB to effectively inhibit liver tumor growth. An integrated approach employing network pharmacology, transcriptomics, and molecular docking implicated the Wnt signaling pathway as a target of the antineoplastic activity of CB by suppressing M2-TAM polarization. In vitro and in vivo experiments further confirmed that CB significantly hinders M2-TAM polarization and suppresses Wnt/ß-catenin pathway activation. The inhibitory effect of CB on M2-TAMs was reversed when treated with the Wnt agonist SKL2001, confirming its pathway specificity. CONCLUSION: This study demonstrated that CB mediates inhibition of M2-TAM polarization through the Wnt/ß-catenin pathway, contributing to the suppression of liver cancer growth.


Subject(s)
Liver Neoplasms , Mice, Nude , Molecular Docking Simulation , Tumor Microenvironment , Tumor-Associated Macrophages , Wnt Signaling Pathway , Wnt Signaling Pathway/drug effects , Animals , Liver Neoplasms/pathology , Liver Neoplasms/drug therapy , Liver Neoplasms/metabolism , Humans , Mice , Hep G2 Cells , Tumor-Associated Macrophages/metabolism , Tumor-Associated Macrophages/drug effects , Tumor-Associated Macrophages/immunology , Tumor Microenvironment/drug effects , Xenograft Model Antitumor Assays , Carcinoma, Hepatocellular/pathology , Carcinoma, Hepatocellular/drug therapy , Carcinoma, Hepatocellular/metabolism , Drugs, Chinese Herbal/pharmacology , Drugs, Chinese Herbal/therapeutic use , Cell Proliferation/drug effects , Mice, Inbred BALB C , Male , Network Pharmacology , beta Catenin/metabolism , Medicine, Chinese Traditional/methods
3.
Psychol Res Behav Manag ; 17: 2727-2737, 2024.
Article in English | MEDLINE | ID: mdl-39070068

ABSTRACT

Purpose: To investigate the influence mechanism of doctor-patient communication on patients' trust, especially the mediating role of patient-physician consistency and the moderating role of perceived threat of disease. Methods: A total of 699 patients in Guangzhou, China was investigated by questionnaire. The main effect, mediating effect, and moderating effect of the model was verified by SPSS23.0 and LISREL8.71 statistical software. Results: It was revealed that doctor-patient communication has a significant positive effect on patients' trust. The consistency between patient and physician partially mediates the relationship between doctor-patient communication and patients' trust. Additionally, the perceived threat of the disease moderates the psychological process through which doctor-patient communication affects patients' trust. Conclusion: Both doctor-patient communication and patient-physician consistency have predictive effects on patients' trust. Doctor-patient communication is not only a direct influence on patient trust but also an indirect influence mediated by patient-physician consistency. Perceived threat of disease moderates the psychological process through which doctor-patient communication affects patients' trust. Specifically, compared to a high level of perceived threat of disease, a low level of perceived threat of disease can enhance the effect of doctor-patient communication on patients' trust. The results of this study underscore the importance of doctor-patient communication and the value of patient-physician consistency for building patients' trust. To foster a harmonious doctor-patient relationship, medical colleges should place great emphasis on cultivating medical students' communication skills. Hospitals should enhance on-the-job training and provide institutional support for doctors, encourage agreements between doctors and patients regarding disease diagnosis and decision-making, and be attentive to patients' perceived threat of disease, particularly for those with high level of perceived threat of disease.

4.
Nat Biomed Eng ; 2024 Jul 18.
Article in English | MEDLINE | ID: mdl-39025943

ABSTRACT

Pt(II) drugs are a widely used chemotherapeutic, yet their side effects can be severe. Here we show that the radiation-induced reduction of Pt(IV) complexes to cytotoxic Pt(II) drugs is rapid, efficient and applicable in water, that it is mediated by hydrated electrons from water radiolysis and that the X-ray-induced release of Pt(II) drugs from an oxaliplatin prodrug in tumours inhibits their growth, as we show with nearly complete tumour regression in mice with subcutaneous human tumour xenografts. The combination of low-dose radiotherapy with a Pt(IV)-based antibody-trastuzumab conjugate led to the tumour-selective release of the chemotherapeutic in mice and to substantial therapeutic benefits. The radiation-induced local reduction of platinum prodrugs in the reductive tumour microenvironment may expand the utility of radiotherapy.

5.
CNS Neurosci Ther ; 30(6): e14802, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38887185

ABSTRACT

BACKGROUND: Glioblastoma multiforme (GBM) is the most aggressive primary brain malignancy. Novel therapeutic modalities like tumor electric field therapy (TEFT) have shown promise, but underlying mechanisms remain unclear. The extracellular matrix (ECM) is implicated in GBM progression, warranting investigation into TEFT-ECM interplay. METHODS: T98G cells were treated with TEFT (200 kHz, 2.2 V/m) for 72 h. Collagen type VI alpha 1 (COL6A1) was identified as hub gene via comprehensive bioinformatic analysis based on RNA sequencing (RNA-seq) and public glioma datasets. TEFT intervention models were established using T98G and Ln229 cell lines. Pre-TEFT and post-TEFT GBM tissues were collected for further validation. Focal adhesion pathway activity was assessed by western blot. Functional partners of COL6A1 were identified and validated by co-localization and survival analysis. RESULTS: TEFT altered ECM-related gene expression in T98G cells, including the hub gene COL6A1. COL6A1 was upregulated in GBM and associated with poor prognosis. Muti-database GBM single-cell analysis revealed high-COL6A1 expression predominantly in malignant cell subpopulations. Differential expression and functional enrichment analyses suggested COL6A1 might be involved in ECM organization and focal adhesion. Western blot (WB), immunofluorescence (IF), and co-immunoprecipitation (Co-IP) experiments revealed that TEFT significantly inhibited expression of COL6A1, hindering its interaction with ITGA5, consequently suppressing the FAK/Paxillin/AKT pathway activity. These results suggested that TEFT might exert its antitumor effects by downregulating COL6A1 and thereby inhibiting the activity of the focal adhesion pathway. CONCLUSION: TEFT could remodel the ECM of GBM cells by downregulating COL6A1 expression and inhibiting focal adhesion pathway. COL6A1 could interact with ITGA5 and activate the focal adhesion pathway, suggesting that it might be a potential therapeutic target mediating the antitumor effects of TEFT.


Subject(s)
Brain Neoplasms , Collagen Type VI , Electric Stimulation Therapy , Glioblastoma , Collagen Type VI/genetics , Collagen Type VI/metabolism , Humans , Glioblastoma/genetics , Glioblastoma/therapy , Glioblastoma/metabolism , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/therapy , Brain Neoplasms/pathology , Electric Stimulation Therapy/methods , Cell Line, Tumor , Animals , Mice, Nude , Mice
6.
Chem Sci ; 15(23): 8934-8945, 2024 Jun 12.
Article in English | MEDLINE | ID: mdl-38873067

ABSTRACT

Many biological processes generally require long-term visualization tools for time-scale dynamic changes of the plasma membrane, but there is still a lack of design rules for such imaging tools based on small-molecule fluorescent probes. Herein, we revealed the key regulatory roles of charge number and species of fluorescent dyes in the anchoring ability of the plasma membrane and found that the introduction of multi-charged units and appropriate charge species is often required for fluorescent dyes with strong plasma membrane anchoring ability by systematically investigating the structure-function relationship of cyanostyrylpyridium (CSP) dyes with different charge numbers and species and their imaging performance for the plasma membrane. The CSP-DBO dye constructed exhibits strong plasma membrane anchoring ability in staining the plasma membrane of cells, in addition to many other advantages such as excellent biocompatibility and general universality of cell types. Such a fluorescent anchor has been successfully used to monitor chemically induced plasma membrane damage and dynamically track various cellular biological events such as cell fusion and cytokinesis over a long period of time by continuously monitoring the dynamic morphological changes of the plasma membrane, providing a valuable precise visualization tool to study the physiological response to chemical stimuli and reveal the structural morphological changes and functions of the plasma membrane during these important biological events from a dynamic perspective. Furthermore, CSP-DBO exhibits excellent biocompatibility and imaging capability in vivo such as labelling the plasma membrane in vivo and monitoring the metabolic process of lipofuscin as an aging indicator.

7.
J Med Chem ; 67(12): 10425-10435, 2024 Jun 27.
Article in English | MEDLINE | ID: mdl-38848302

ABSTRACT

Hexadimethrine bromide (HB), a synthetic polycationic species, was introduced to clinical practice as a heparin antidote and recently used in gene therapy. However, HB causes various complications such as severe red blood cells (RBCs) aggregation and tissue damage. Herein, we have synthesized a water-soluble quaterphen[3]arene containing multiple sulfonate moieties (SQP3) as a novel macrocyclic neutralizer to reverse HB via direct host-guest complexation. SQP3 exhibited a robust binding affinity toward HB with a considerably high association constant of (4.73 ± 0.61) × 107 M-1. Co-dosed with 1 equiv of SQP3, HB-induced RBCs aggregation and blood coagulation could be effectively reversed. In vitro cellular assay verified that complexation of HB with SQP3 significantly decreased reactive oxygen species production, thereby suppressing cell apoptosis. In vivo neutralization efficacy studies demonstrated that HB/SQP3 was capable of alleviating related organic damage caused by HB and improving the survival rate of HB-treated mice from 20 to 100%.


Subject(s)
Macrocyclic Compounds , Animals , Mice , Humans , Macrocyclic Compounds/chemistry , Macrocyclic Compounds/pharmacology , Macrocyclic Compounds/chemical synthesis , Reactive Oxygen Species/metabolism , Apoptosis/drug effects , Erythrocyte Aggregation/drug effects , Sulfonic Acids/chemistry , Sulfonic Acids/pharmacology
8.
Accid Anal Prev ; 205: 107668, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38889599

ABSTRACT

The safety of two-wheelers is a serious public safety issue nowadays. Two-wheelers usually have severe conflict interaction with vehicles at intersections, such as running red lights, which is very likely to cause traffic accidents. Therefore, a model of two-wheeler driving behavior in conflicting interactions can provide guidance for traffic safety management on one hand, and can be used for the development and testing of autonomous vehicles on the other. However, the existing models perform poorly when interacting with vehicles. To address the problems, this paper proposes a modeling method (an improved social force model, ISFM) for two-dimensional two-wheeler driving simulation for conflict interaction at intersections. Based on analysis of naturalistic driving study data, when two-wheelers encounter with vehicles, their driving intentions and trajectories can be categorized into two groups, which are yielding and overtaking. Therefore, the vehicle-related social forces are designed to be a set of two forces rather than a repulsion force in original SFM, which is a yielding force based on the relative distance between the two-wheeler and the vehicle, and an overtaking force based on the velocity of the two-wheeler itself. This opens up the possibilities for modeling the multi-modal driving intention of two-wheelers encountering with cross traffic. Based on ISFM, a bicycle model, a powered two-wheeler (PTW) model and a model of a group of PTWs, are then constructed. Compared to the original SFM, ISFM increases the precision of driving intention prediction by 19.7 % (yielding situation) and 25.0 % (overtaking situation), and reduces the root mean square error between simulated and actual trajectories by 7.8 % and 14.8 % on the bicycle model and the PTW model, respectively. Meanwhile, the model of a group of PTWs also performs well. Finally, the results of ablation experiments also validate the effectiveness of the social force designed based on velocity.


Subject(s)
Accidents, Traffic , Automobile Driving , Humans , Automobile Driving/psychology , Accidents, Traffic/prevention & control , Male , Models, Theoretical , Adult , Intention , Motorcycles , Female , Safety , Young Adult
9.
J Neurosurg Spine ; 41(2): 246-253, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38759244

ABSTRACT

OBJECTIVE: The aim of this study was to investigate the predictive value of different site-specific MRI-based assessments of bone quality for cage subsidence among patients undergoing oblique lumbar interbody fusion (OLIF) with or without posterior internal fixation. METHODS: The authors retrospectively reviewed the records of patients who underwent OLIF between 2017 and 2022. Endplate bone quality (EBQ), mean vertebral bone quality (MVBQ), and vertebral bone quality (VBQ) scores were measured using preoperative non-contrast-enhanced T1-weighted MRI of the lumbar spine. Logistic regression analysis was used to identify factors associated with cage subsidence. Receiver operating characteristic curve analysis was used to evaluate the value of different site-specific MRI-based assessments of bone quality in predicting cage subsidence. RESULTS: Of the 124 patients who underwent OLIF, subsidence was found in 42 (33.9%). The VBQ, MVBQ, and EBQ scores were higher in the subsidence group than in the no-subsidence group. In the stand-alone OLIF (SA-OLIF) group, logistic regression analysis showed that the EBQ score was significantly associated with subsidence (OR 13.656, 95% CI 2.561-72.806; p = 0.002). Furthermore, the areas under the curve (AUCs) for using the VBQ, MVBQ, and EBQ scores and T-score to predict cage subsidence were 0.684, 0.683, 0.745, and 0.685, respectively. In the OLIF with posterior internal fixation (OLIF-PF) group, logistic regression analysis showed that the MVBQ score was significantly associated with subsidence (OR 8.301, 95% CI 2.064-33.385; p = 0.003). The AUCs for using the VBQ score, MVBQ score, and T-score to predict cage subsidence were 0.757, 0.774, and 0.685, respectively. CONCLUSIONS: There are significant differences in the predictive value of different site-specific bone quality assessments for cage subsidence among patients undergoing OLIF. For SA-OLIF, the EBQ score is recommended, while for OLIF-PF, the VBQ score is preferable.


Subject(s)
Lumbar Vertebrae , Magnetic Resonance Imaging , Spinal Fusion , Humans , Spinal Fusion/methods , Spinal Fusion/instrumentation , Male , Female , Lumbar Vertebrae/surgery , Lumbar Vertebrae/diagnostic imaging , Middle Aged , Magnetic Resonance Imaging/methods , Retrospective Studies , Aged , Predictive Value of Tests , Adult
10.
Adv Sci (Weinh) ; 11(28): e2306217, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38742466

ABSTRACT

Radiation proctopathy (RP) is a common complication of radiotherapy for pelvic malignancies with high incidence. RP accompanies by microbial dysbiosis. However, how the gut microbiota affects the disease remains unclear. Here, metabolomics reveals that the fecal and serous concentrations of microbiota-derived 3-hydroxybutyrate (3HB) are significantly reduced in RP mice and radiotherapeutic patients. Moreover, the concentration of 3HB is negatively associated with the expression of proinflammatory IL6 that is increased along with the severity of radiation damage. 3HB treatment significantly downregulates IL6 expression and alleviates IL6-mediated radiation damage. Irradiated cell-fecal microbiota co-culture experiments and in vivo assays show that such a radioprotection of 3HB is mediated by GPR43. Microbiome analysis reveals that radiation leads to a distinct bacterial community compared to untreated controls, in which Akkermansia muciniphila is significantly reduced in RP mice and radiotherapeutic patients and is associated with lower 3HB concentration. Gavage of A. muciniphila significantly increases 3HB concentration, downregulates GPR43 and IL6 expression, and ameliorates radiation damage. Collectively, these results demonstrate that the gut microbiota, including A. muciniphila, induce higher concentrations of 3HB to block GPR43-mediated IL6 signaling, thereby conferring radioprotection. The findings reveal a novel implication of the gut-immune axis in radiation pathophysiology, with potential therapeutic applications.


Subject(s)
3-Hydroxybutyric Acid , Gastrointestinal Microbiome , Interleukin-6 , Receptors, G-Protein-Coupled , Signal Transduction , Animals , Mice , Interleukin-6/metabolism , Interleukin-6/genetics , Receptors, G-Protein-Coupled/metabolism , Receptors, G-Protein-Coupled/genetics , 3-Hydroxybutyric Acid/metabolism , 3-Hydroxybutyric Acid/pharmacology , Humans , Radiation Injuries/metabolism , Disease Models, Animal , Proctitis/metabolism , Mice, Inbred C57BL , Male , Akkermansia/metabolism
11.
CNS Neurosci Ther ; 30(5): e14720, 2024 05.
Article in English | MEDLINE | ID: mdl-38715344

ABSTRACT

BACKGROUND: Glioblastoma multiforme (GBM) is an aggressive malignant tumor with a high mortality rate and is the most prevalent primary intracranial tumor that remains incurable. The current standard treatment, which involves surgery along with concurrent radiotherapy and chemotherapy, only yields a survival time of 14-16 months. However, the introduction of tumor electric fields therapy (TEFT) has provided a glimmer of hope for patients with newly diagnosed and recurrent GBM, as it has been shown to extend the median survival time to 20 months. The combination of TEFT and other advanced therapies is a promising trend in the field of GBM, facilitated by advancements in medical technology. AIMS: In this review, we provide a concise overview of the mechanism and efficacy of TEFT. In addition, we mainly discussed the innovation of TEFT and our proposed blueprint for TEFT implementation. CONCLUSION: Tumor electric fields therapy is an effective and highly promising treatment modality for GBM. The full therapeutic potential of TEFT can be exploited by combined with other innovative technologies and treatments.


Subject(s)
Brain Neoplasms , Electric Stimulation Therapy , Glioblastoma , Humans , Glioblastoma/therapy , Brain Neoplasms/therapy , Electric Stimulation Therapy/methods , Electric Stimulation Therapy/trends , Animals
12.
Nature ; 630(8015): 206-213, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38778111

ABSTRACT

Targeted radionuclide therapy, in which radiopharmaceuticals deliver potent radionuclides to tumours for localized irradiation, has addressed unmet clinical needs and improved outcomes for patients with cancer1-4. A therapeutic radiopharmaceutical must achieve both sustainable tumour targeting and fast clearance from healthy tissue, which remains a major challenge5,6. A targeted ligation strategy that selectively fixes the radiopharmaceutical to the target protein in the tumour would be an ideal solution. Here we installed a sulfur (VI) fluoride exchange (SuFEx) chemistry-based linker on radiopharmaceuticals to prevent excessively fast tumour clearance. When the engineered radiopharmaceutical binds to the tumour-specific protein, the system undergoes a binding-to-ligation transition and readily conjugates to the tyrosine residues through the 'click' SuFEx reaction. The application of this strategy to a fibroblast activation protein (FAP) inhibitor (FAPI) triggered more than 80% covalent binding to the protein and almost no dissociation for six days. In mice, SuFEx-engineered FAPI showed 257% greater tumour uptake than did the original FAPI, and increased tumour retention by 13-fold. The uptake in healthy tissues was rapidly cleared. In a pilot imaging study, this strategy identified more tumour lesions in patients with cancer than did other methods. SuFEx-engineered FAPI also successfully achieved targeted ß- and α-radionuclide therapy, causing nearly complete tumour regression in mice. Another SuFEx-engineered radioligand that targets prostate-specific membrane antigen (PSMA) also showed enhanced therapeutic efficacy. Considering the broad scope of proteins that can potentially be ligated to SuFEx warheads, it might be possible to adapt this strategy to other cancer targets.


Subject(s)
Molecular Targeted Therapy , Prostatic Neoplasms , Radioisotopes , Radiopharmaceuticals , Animals , Humans , Male , Mice , Antigens, Surface/chemistry , Antigens, Surface/metabolism , Cell Line, Tumor , Fluorides/chemistry , Fluorides/metabolism , Glutamate Carboxypeptidase II/chemistry , Glutamate Carboxypeptidase II/metabolism , Ligands , Membrane Proteins/metabolism , Membrane Proteins/chemistry , Molecular Targeted Therapy/methods , Pilot Projects , Prostatic Neoplasms/metabolism , Prostatic Neoplasms/radiotherapy , Radioisotopes/therapeutic use , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/therapeutic use , Radiopharmaceuticals/metabolism , Radiopharmaceuticals/pharmacokinetics , Sulfur Compounds/chemistry , Sulfur Compounds/metabolism , Tyrosine/metabolism , Tyrosine/chemistry , Xenograft Model Antitumor Assays
13.
Chem Commun (Camb) ; 60(43): 5598-5601, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38712724

ABSTRACT

A simple aqueous host:guest sensing array can selectively discriminate between different types of citrus varietal from peel extract samples. It can also distinguish between identical citrus samples at varying stages of ripening. The discrimination effects stem from detection of changes in the terpenoid composition of the peel extracts by the host:guest array, despite the overwhelming excess of a single component, limonene, in each sample. The hosts are insensitive to limonene but bind other monoterpenes strongly, even though they are similar in structure to the major limonene component. This work demonstrates the capability of host:guest arrays in sensing target molecules in environments with the competing agents present at high abundances in the sample matrix.


Subject(s)
Citrus , Terpenes , Citrus/chemistry , Terpenes/chemistry , Terpenes/analysis , Limonene/chemistry , Limonene/analysis , Fruit/chemistry
14.
Biomacromolecules ; 25(5): 3122-3130, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38696355

ABSTRACT

Synthesis of polysaccharide-b-polypeptide block copolymers represents an attractive goal because of their promising potential in delivery applications. Inspired by recent breakthroughs in N-carboxyanhydride (NCA) ring-opening polymerization (ROP), we present an efficient approach for preparation of a dextran-based macroinitiator and the subsequent synthesis of dextran-b-polypeptides via NCA ROP. This is an original approach to creating and employing a native polysaccharide macroinitiator for block copolymer synthesis. In this strategy, regioselective (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) oxidation of the sole primary alcohol located at the C-6 position of the monosaccharide at the nonreducing end of linear dextran results in a carboxylic acid. This motif is then transformed into a tetraalkylammonium carboxylate, thereby generating the dextran macroinitiator. This macroinitiator initiates a wide range of NCA monomers and produces dextran-b-polypeptides with a degree of polymerization (DP) of the polypeptide up to 70 in a controlled manner (D < 1.3). This strategy offers several distinct advantages, including preservation of the original dextran backbone structure, relatively rapid polymerization, and moisture tolerance. The dextran-b-polypeptides exhibit interesting self-assembly behavior. Their nanostructures have been investigated by dynamic light scattering (DLS) and transmission electron microscopy (TEM), and adjustment of the structure of block copolymers allows self-assembly of spherical micelles and worm-like micelles with varied diameters and aspect ratios, revealing a range of diameters from 60 to 160 nm. Moreover, these nanostructures exhibit diverse morphologies, including spherical micelles and worm-like micelles, enabling delivery applications.


Subject(s)
Dextrans , Peptides , Polymerization , Dextrans/chemistry , Peptides/chemistry , Peptides/chemical synthesis , Polymers/chemistry , Polymers/chemical synthesis , Cyclic N-Oxides/chemistry , Anhydrides/chemistry , Polysaccharides/chemistry , Micelles
15.
Biomacromolecules ; 25(6): 3642-3650, 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38775327

ABSTRACT

The preparation of polysaccharide-peptide hydrogels usually involves multiple synthetic steps, thus reducing the effectiveness and practicality of these approaches. Inspired by recent discoveries in aqueous N-carboxyanhydride (NCA) ring-opening polymerization (ROP) and ring-opening polymerization-induced nanogelation, we present an aqueous one-pot strategy to prepare polysaccharide-polypeptide hydrogels. In this study, water-soluble polysaccharide carboxymethyl chitosan is used as the macromolecular initiator to prepare polysaccharide-polypeptide copolymers through the aqueous ROP of NCA. The catalyst-free approach afforded hydrogels with properties that could be controlled by adjusting the type and amount of NCA used, with the elastic modulus ranging from 50 Pa to 18000 Pa. The hydrogen bond-cross-linked hydrogel exhibited self-healing and injectable properties. Morphology characterization revealed that micelles were formed in the early stage of reaction, suggesting that the polymerization follows an aqueous ring-opening polymerization-induced self-assembly (ROPISA) mechanism and that aggregation of micelles during the reaction caused the gelation. Moreover, the hydrogels displayed high swelling ratios (>95% water content), and hemolysis and cytotoxicity experiments demonstrated that the hydrogels had excellent biocompatibility, indicating their potential in medical applications.


Subject(s)
Hydrogels , Hydrogels/chemistry , Hydrogels/chemical synthesis , Hydrogels/pharmacology , Polymerization , Chitosan/chemistry , Chitosan/analogs & derivatives , Peptides/chemistry , Water/chemistry , Humans , Biocompatible Materials/chemistry , Biocompatible Materials/chemical synthesis , Polysaccharides/chemistry , Micelles , Animals
16.
Sci Rep ; 14(1): 8646, 2024 04 15.
Article in English | MEDLINE | ID: mdl-38622188

ABSTRACT

Human activities have increased with urbanisation in the Erhai Lake Basin, considerably impacting its eco-environmental quality (EEQ). This study aims to reveal the evolution and driving forces of the EEQ using water benefit-based ecological index (WBEI) in response to human activities and policy variations in the Erhai Lake Basin from 1990 to 2020. Results show that (1) the EEQ exhibited a pattern of initial degradation, subsequent improvement, further degradation and a rebound from 1990 to 2020, and the areas with poor and fair EEQ levels mainly concentrated around the Erhai Lake Basin with a high level of urbanisation and relatively flat terrain; (2) the EEQ levels were not optimistic in 1990, 1995 and 2015, and areas with poor and fair EEQ levels accounted for 43.41%, 47.01% and 40.05% of the total area, respectively; and (3) an overall improvement in the EEQ was observed in 1995-2000, 2000-2005, 2005-2009 and 2015-2020, and the improvement was most significant in 1995-2000, covering an area of 823.95 km2 and accounting for 31.79% of the total area. Results also confirmed that the EEQ changes in the Erhai Lake Basin were primarily influenced by human activities and policy variations. Moreover, these results can provide a scientific basis for the formulation and planning of sustainable development policy in the Erhai Lake Basin.


Subject(s)
Lakes , Sustainable Development , Humans , Human Activities , China , Environmental Monitoring/methods
17.
Chem Commun (Camb) ; 60(39): 5209-5212, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38652058

ABSTRACT

A practical carbon dioxide (CO2) conversion and utilization system shows great potential for ameliorating the greenhouse effect. Herein, an integrated carbon aerogel-based photothermal catalysis microreactor with photothermal conversion, enhanced mass transfer adsorption and a thermal catalytic reactor is designed. As a solar-powered CO2 utilization module, this microreactor can conveniently convert CO2 into economically valuable products without elaborate equipment and operation processes.

18.
Nat Chem ; 16(8): 1348-1356, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38561425

ABSTRACT

Radiotherapy-induced prodrug activation provides an ideal solution to reduce the systemic toxicity of chemotherapy in cancer therapy, but the scope of the radiation-activated protecting groups is limited. Here we present that the well-established photoinduced electron transfer chemistry may pave the way for developing versatile radiation-removable protecting groups. Using a functional reporter assay, N-alkyl-4-picolinium (NAP) was identified as a caging group that efficiently responds to radiation by releasing a client molecule. When evaluated in a competition experiment, the NAP moiety is more efficient than other radiation-removable protecting groups discovered so far. Leveraging this property, we developed a NAP-derived carbamate linker that releases fluorophores and toxins on radiation, which we incorporated into antibody-drug conjugates (ADCs). These designed ADCs were active in living cells and tumour-bearing mice, highlighting the potential to use such a radiation-removable protecting group for the development of next-generation ADCs with improved stability and therapeutic effects.


Subject(s)
Prodrugs , Prodrugs/chemistry , Prodrugs/pharmacology , Animals , Humans , Mice , Immunoconjugates/chemistry , Immunoconjugates/pharmacology , Cell Line, Tumor , Neoplasms/drug therapy , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Female
19.
Heliyon ; 10(7): e28448, 2024 Apr 15.
Article in English | MEDLINE | ID: mdl-38576581

ABSTRACT

Background: To develop a model for the accurate prediction of calculous obstructive pyonephrosis prior to percutaneous nephrolithotomy (PNL), leading to early local anaesthesia microchannel nephrostomy for drainage of pyonephrosis. Methods: By comparing the differences in baseline clinical indicators between the pyonephrosis group and nonpyonephrosis groups, independent risk factors were screened out, and a diagnostic alignment diagram model for predicting calculus obstructive pyonephrosis before PNL was established. Results: Multivariate regression analysis showed that preoperative blood neutrophil count (Neu), serum creatinine level (Scr), serum albumin level (Alb), urine nitrite (UN), hydronephrosis density (HD) and fever history within one month (HFWOM) were independent risk factors for calculous obstructive pyonephrosis. The AUC value of the receiver operating characteristic (ROC) curve was 0.929. The calibration curves showed that the predictive model was well corrected and that the predictive model had strong consistency. Decision analysis curves showed good clinical efficacy of the model. Conclusion: The alignment diagram model accurately predicts patients with preoperative calculous obstructive pyonephrosis in the PNL and provides an evidence-based basis for early renal microchannel nephrostomy.

20.
Cancer Sci ; 115(6): 1749-1762, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38508217

ABSTRACT

N6-Methyladenosine (m6A) is a important process regulating gene expression post-transcriptionally. Programmed death ligand 1 (PD-L1) is a major immune inhibitive checkpoint that facilitates immune evasion and is expressed in tumor cells. In this research we discovered that Wilms' tumor 1-associated protein (WTAP) degradation caused by ubiquitin-mediated cleavage in cancer cells (colorectal cancer, CRC) under hypoxia was inhibited by Pumilio homolog 1 (PUM1) directly bound to WTAP. WTAP enhanced PD-L1 expression in a way that was m6A-dependent. m6A "reader," Insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) identified methylated PD-L1 transcripts and subsequently fixed its mRNA. Additionally, we found that T-cell proliferation and its cancer cell-killing effects were prevented by overexpression of WTAP in vitro and in vivo. Overexpression prevented T cells from proliferating and killing CRC by maintaining the expression of PD-L1. Further evidence supporting the WTAP-PD-L1 regulatory axis was found in human CRC and organoid tissues. Tumors with high WTAP levels appeared more responsive to anti-PD1 immunotherapy, when analyzing samples from patients undergoing treatment. Overall, our findings demonstrated a novel PD-L1 regulatory mechanism by WTAP-induced mRNA epigenetic regulation and the possible application of targeting WTAP as immunotherapy for tumor hypoxia.


Subject(s)
Adenosine , B7-H1 Antigen , Colorectal Neoplasms , Humans , Adenosine/analogs & derivatives , Adenosine/metabolism , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Colorectal Neoplasms/immunology , Colorectal Neoplasms/metabolism , B7-H1 Antigen/metabolism , B7-H1 Antigen/genetics , Animals , Mice , Cell Line, Tumor , RNA-Binding Proteins/metabolism , RNA-Binding Proteins/genetics , T-Lymphocytes/immunology , T-Lymphocytes/metabolism , Cell Proliferation , Gene Expression Regulation, Neoplastic , RNA Splicing Factors/genetics , RNA Splicing Factors/metabolism , Female , Tumor Hypoxia/genetics , Cell Cycle Proteins
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