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1.
Proc Natl Acad Sci U S A ; 119(45): e2213162119, 2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36322757

RESUMEN

Temporal lobe epilepsy (TLE) is one of the most common types of epilepsy, yet approximately one-third of patients are refractory to current anticonvulsive drugs, which target neurons and synapses. Astrocytic and microglial dysfunction is commonly found in epileptic foci and has been shown to contribute to neuroinflammation and hyperexcitability in chronic epilepsy. Accumulating evidence points to a key role for glial hemichannels in epilepsy, but inhibiting both connexin (Cx) gap junctions and hemichannels can lead to undesirable side effects because the former coordinate physiological functions of cell assemblies. It would be a great benefit to use an orally available small molecule to block hemichannels to alleviate epileptic symptoms. Here, we explored the effect of D4, a newly developed compound that inhibits the Cx hemichannels but not Cx gap junctions using the pilocarpine mouse model of TLE. In vitro application of D4 caused a near-complete reduction in the pilocarpine-induced cell membrane permeability associated with increased Cx hemichannel activity. Moreover, preadministration of D4 in vivo effectively reduced neuroinflammation and altered synaptic inhibition, which then enhanced the animal survival rate. Posttreatment with a single dose of D4 in vivo has prolonged effects on suppressing the activation of astrocytes and microglia and rescued the changes in neuroinflammatory and synaptic gene expression induced by pilocarpine. Collectively, these results indicate that targeting Cx hemichannels by D4 is an effective and promising strategy for treating epilepsy in which neuroinflammation plays a critical role.


Asunto(s)
Epilepsia del Lóbulo Temporal , Epilepsia , Animales , Ratones , Conexinas/metabolismo , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Epilepsia del Lóbulo Temporal/metabolismo , Pilocarpina , Enfermedades Neuroinflamatorias
2.
Chemistry ; 30(8): e202303306, 2024 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-37965800

RESUMEN

The development of soft photoactuators with multifunctionality and improved performance is highly important for their broad applications. Herein, we report on a facile and efficient strategy for fabricating such photoactuators with UV-NIR dual light-responsivity, room-temperature 3D shape reprogrammability and reprocessability, and photothermal healability by doping polydopamine (PDA) nanoparticles into a main-chain azobenzene semi-crystalline poly(ester-amide) (PEA). The PEA/PDA nanoparticle composite was readily processed into free-standing films with enhanced mechanical and photomechanical properties compared with the blank PEA films. Its physically crosslinked uniaxially oriented films showed rapid and highly reversible photochemically induced bending/unbending under the UV/visible light irradiation at room temperature in both the air atmosphere and water. When exposed to the NIR light, they (and their bilayer films formed with a polyimide film) exhibited photothermally induced bending even at a temperature much lower than their crystalline-to-isotropic phase transition temperature based on a unique mechanism (involving photothermally induced polymer chain relaxation due to the disruption of their hydrogen bonds). The room-temperature 3D shape reprogrammability and reprocessability and photothermal healability of the composite polymer films were also demonstrated. Such multifunctional dual light-responsive photoactuators with well-balanced mechanical robustness, actuation stability, 3D shape reprogrammability/reprocessability and photothermal healability hold much promise in various photoactuating applications.

3.
Small ; 19(31): e2206667, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-36651015

RESUMEN

Obesity is a major global health problem that significantly increases the risk of many other diseases. Herein, a facile method of suppressing lipogenesis and obesity using L-arginine-functionalized carbon dots (L-Arg@CDots) is reported. The prepared CDots with a negative surface charge form stronger bonds than D-arginine and lysine with L-Arg in water. The L-Arg@CDots in the aqueous solution offer a high photoluminescence quantum yield of 23.6% in the red wavelength region. The proposed L-Arg functionalization strategy not only protects the red emission of the CDots from quenching by water molecules but also enhances the intracellular uptake of L-Arg to reduce lipogenesis. Injection of L-Arg@CDots can reduce the body weight increase in ob/ob mice by suppressing their food intake and shrinking the white adipose tissue cells, thereby significantly inhibiting obesity.


Asunto(s)
Carbono , Puntos Cuánticos , Ratones , Animales , Carbono/química , Obesidad , Arginina , Puntos Cuánticos/química
4.
Molecules ; 28(3)2023 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-36770744

RESUMEN

The development of complex biological sample-compatible fluorescent molecularly imprinted polymers (MIPs) with improved performances is highly important for their real-world bioanalytical and biomedical applications. Herein, we report on the first hydrophilic "turn-on"-type fluorescent hollow MIP microparticles capable of directly, highly selectively, and rapidly optosensing hippuric acid (HA) in the undiluted human urine samples. These fluorescent hollow MIP microparticles were readily obtained through first the synthesis of core-shell-corona-structured nitrobenzoxadiazole (NBD)-labeled hydrophilic fluorescent MIP microspheres by performing one-pot surface-initiated atom transfer radical polymerization on the preformed "living" silica particles and subsequent removal of their silica core via hydrofluoric acid etching. They showed "turn-on" fluorescence and high optosensing selectivity and sensitivity toward HA in the artificial urine (the limit of detection = 0.097 µM) as well as outstanding photostability and reusability. Particularly, they exhibited much more stable aqueous dispersion ability, significantly faster optosensing kinetics, and higher optosensing sensitivity than their solid counterparts. They were also directly used for quantifying HA in the undiluted human urine with good recoveries (96.0%-102.0%) and high accuracy (RSD ≤ 4.0%), even in the presence of several analogues of HA. Such fluorescent hollow MIP microparticles hold much promise for rapid and accurate HA detection in the clinical diagnostic field.


Asunto(s)
Impresión Molecular , Polímeros Impresos Molecularmente , Humanos , Polímeros , Colorantes , Dióxido de Silicio
5.
Molecules ; 28(10)2023 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-37241914

RESUMEN

Fully room temperature three-dimensional (3D) shape-reprogrammable, recyclable, and photomobile azobenzene (azo) polymer actuators hold much promise in many photoactuating applications, but their development is challenging. Herein, we report on the efficient synthesis of a series of main-chain azo liquid crystalline polymers (LCPs) with such performances via Michael addition polymerization. They have both ester groups and two kinds of hydrogen bond-forming groups (i.e., amide and secondary amino groups) and different flexible spacer length in the backbones. Such poly(ester-amide-secondary amine)s (PEAsAs) show low glass transition temperatures (Tg ≤ 18.4 °C), highly ordered smectic liquid crystalline phases, and reversible photoresponsivity. Their uniaxially oriented fibers fabricated via the melt spinning method exhibit good mechanical strength and photoinduced reversible bending/unbending and large stress at room temperature, which are largely influenced by the flexible spacer length of the polymers. Importantly, all these fibers can be easily reprogrammed under strain at 25 °C into stable fiber springs capable of showing a totally different photomobile mode (i.e., unwinding/winding), mainly owing to the presence of low Tg and both dynamic hydrogen bonding and stable crystalline domains (induced by the uniaxial drawing during the fiber formation). They can also be recycled from a solution at 25 °C. This work not only presents the first azo LCPs with 3D shape reprogrammability, recyclability, and photomobility at room temperature, but also provides some important knowledge of their structure-property relationship, which is useful for designing more advanced photodeformable azo polymers.

6.
Pak J Med Sci ; 39(2): 344-348, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36950391

RESUMEN

Objective: To evaluate the clinical efficacy of continuous veno-venous hemofiltration (CVVH) combined with hemoperfusion for the treatment of multiple myeloma (MM) complicated with acute kidney injury (AKI). Methods: Medical records of 73 patients with MM complicated with AKI admitted to the First People's Hospital of Huzhou from January 2019 to January 2021 were retrospectively analyzed. According to the treatment records, 35 patients received simple chemotherapy (control group), and 38 patients received CVVH combined with HP on the basis of chemotherapy (observation group). We compared the clinical efficacies, renal function indexes, and the serum globulin and erythrocyte sedimentation rate (ESR) values between the two groups. Results: After the treatment, the total efficacy of the observation group was significantly higher (81.58%) than that in the control group (57.14%; p <0.05). Serum cystatin C (CysC), urea nitrogen (BUN), ß2 macroglobulin (ß2-MG) and creatinine (SCr) levels were significantly lower in the observation group than in the control group (p <0.05). Serum globulin level and ESR values in the observation group after the treatment were also significantly lower than in the control group (p <0.05). Conclusions: The outcomes of patients with MM complicated with AKI treated with CVVH and hemoperfusion differ significantly from those of the patients treated only with CVVH. Combining CVVH and hemoperfusion helps to improve the efficacy of the treatment, promotes renal function recovery, and improves the levels of serum globulin and ESR.

7.
J Cell Physiol ; 237(1): 949-964, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34491578

RESUMEN

Signaling by neurotrophins such as the brain-derived neurotrophic factor (BDNF) is known to modulate development of interneurons, but the circuit effects of this modulation remain unclear. Here, we examined the impact of deleting TrkB, a BDNF receptor, in parvalbumin-expressing (PV) interneurons on the balance of excitation and inhibition (E-I) in cortical circuits. In the mouse olfactory cortex, TrkB deletion impairs multiple aspects of PV neuronal function including synaptic excitation, intrinsic excitability, and the innervation pattern of principal neurons. Impaired PV cell function resulted in aberrant spiking patterns in principal neurons in response to stimulation of sensory inputs. Surprisingly, dampened PV neuronal function leads to a paradoxical decrease in overall excitability in cortical circuits. Our study demonstrates that, by modulating PV circuit plasticity and development, TrkB plays a critical role in shaping the evoked pattern of activity in a cortical network.


Asunto(s)
Parvalbúminas , Receptor trkB , Animales , Interneuronas/fisiología , Ratones , Neuronas , Parvalbúminas/genética , Receptor trkB/genética
8.
Mikrochim Acta ; 189(12): 464, 2022 11 23.
Artículo en Inglés | MEDLINE | ID: mdl-36424480

RESUMEN

The efficient preparation of ratiometric fluorescent molecularly imprinted polymer (MIP) microspheres that can directly and selectively optosense a herbicide (i.e., 2,4-dichlorophenoxyacetic acid, 2,4-D) in undiluted pure milk is described. The dual fluorescent MIP microparticles were readily obtained through grafting a green 4-nitrobenzo[c][1,2,5]oxadiazole (NBD)-labeled 2,4-D-MIP layer with hydrophilic polymer brushes onto the preformed uniform "living" red CdTe quantum dot (QD)-labeled SiO2 microspheres via one-pot surface-initiated atom transfer radical polymerization (SI-ATRP) in the presence of a polyethylene glycol macro-ATRP initiator. They proved to be highly promising "turn-on"-type fluorescent chemosensors with red CdTe QD (the maximum emission wavelength λe,max around 710 nm) and green NBD (λe,max around 515 nm) as the reference fluorophore and "turn-on"-type responsive fluorophore, respectively. The sensors showed excellent photostability and reusability, high 2,4-D selectivity and sensitivity (the limit of detection = 0.12 µM), and direct visual detection ability (a fluorescent color change occurs from red to blue-green with the concentration of 2,4-D increasing from 0 to 100 µM) in pure bovine milk. The sensors were used for 2,4-D detection with high recoveries (96.0-104.0%) and accuracy (RSD ≤ 4.0%) in pure goat milk at three spiking levels of both 2,4-D and its mixtures with several analogues. This new strategy lays the foundation for efficiently developing diverse complex biological sample-compatible ratiometric fluorescent MIPs highly useful for real-world bioanalyses and diagnostics.


Asunto(s)
Compuestos de Cadmio , Herbicidas , Impresión Molecular , Puntos Cuánticos , Polímeros Impresos Molecularmente , Microesferas , Telurio , Dióxido de Silicio , Herbicidas/análisis , Ácido 2,4-Diclorofenoxiacético/análisis
9.
Zhongguo Zhong Yao Za Zhi ; 47(4): 1103-1113, 2022 Feb.
Artículo en Zh | MEDLINE | ID: mdl-35285211

RESUMEN

At present, there have been many clinical trials and systematic reviews/Meta-analysis proving the good clinical efficacy of Shufeng Jiedu Capsules in the treatment of respiratory diseases, while comprehensive discussion is still required. This article overviews and analyzes the systematic reviews/Meta-analysis of Shufeng Jiedu Capsules to provide evidence support for clinical practice. The systematic reviews/Meta-analysis of Shufeng Jiedu Capsules were searched from CBM, Wanfang, CNKI, VIP, PubMed, EMbase and Cochrane Library. The AMSTAR 2 scale and GRADE system were respectively employed for the evaluation of methodological quality and the grading of evidence quality. Finally, 8 systematic reviews/Meta-analysis published during 2018-2021 were included for analysis. The diseases involved include acute exacerbation of chronic obstructive pulmonary disease, community-acquired pneumonia, acute tonsillitis, acute exacerbation of chronic bronchitis and acute upper respiratory tract infection. The number of included RCTs studies ranged from 8 to 25. The results showed that Shufeng Jiedu Capsules combined with western medicine routine had better therapeutic effect than the latter alone in the treatment of the above five diseases. The reported adverse reactions caused by Shufeng Jiedu Capsules were mainly gastrointestinal discomforts such as mild nausea, diarrhoea and vomiting, with low incidence and mild symptoms, which can be relieved by drug withdrawal. The methodological quality of the included studies was extremely low, and the outcome indicators were mainly of low and very low grades. The efficacy and safety of Shufeng Jiedu Capsules in the clinical treatment of diseases still need to be verified based on more high-quality studies. The relevant clinical research and systematic review/Meta-analysis should pay more attention to methodological quality and reporting standards and strengthen the scientificity of research.


Asunto(s)
Medicamentos Herbarios Chinos , Cápsulas , Medicamentos Herbarios Chinos/uso terapéutico , Revisiones Sistemáticas como Asunto , Resultado del Tratamiento
10.
Molecules ; 26(15)2021 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-34361608

RESUMEN

Photodeformable azobenzene (azo) polymers are a class of smart polymers that can efficiently convert light energy into mechanical power, holding great promise in various photoactuating applications. They are typically of crosslinked polymer networks with highly oriented azo mesogens embedded inside. Upon exposure to the light of appropriate wavelength, they experience dramatic order parameter change following the configuration change of the azo units. This could result in the generation and accumulation of the gradient microscopic photomechanical force in the crosslinked polymer networks, thus leading to their macroscopic deformation. So far, a great number of photodeformable azo polymers have been developed, including some unoriented ones showing photodeformation based on different mechanisms. Among them, photodeformable azo polymers with dynamic crosslinking networks (and some uncrosslinked ones) have aroused particular interest recently because of their obvious advantages over those with stable chemical crosslinking structures such as high recyclability and reprocessability. In this paper, I provide a detailed overview of the recent progress in such reprocessable photodeformable polymers. In addition, some challenges and perspectives are also presented.

11.
Angew Chem Int Ed Engl ; 60(4): 2018-2023, 2021 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-32885573

RESUMEN

A new and simple strategy towards electric-field-driven multiple chirality switching device has been designed and fabricated by combining a newly synthesized base-responsive chiroptical polymer switch (R-FLMA) and p-benzoquinone (p-BQ) via proton-coupled electron transfer (PCET) mechanism. Clear and stable triple chirality states (silence, positive, negative) of this device in visible band can be regulated reversibly (>1000 cycles) by adjusting voltage programs. Furthermore, such chiral switching phenomena are also accompanied by apparent changes of color and fluorescence. More importantly, the potential application of this device for a spatial light modulator has also been demonstrated.

12.
Langmuir ; 36(41): 12403-12413, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32969664

RESUMEN

Ratiometric fluorescent molecularly imprinted polymer (MIP) sensors hold great promise in many bioanalytical areas because of their high sensitivity and selectivity as well as excellent self-referencing and visual detection capability. However, their synthetic strategies are rather limited and the development of such optosensing MIPs that can directly and selectively quantify small organic analytes in complex biological samples remains a formidable challenge owing to the complexity of sample matrices. Herein, a versatile and modular strategy to obtaining well-defined ratiometric fluorescent MIP microspheres capable of directly and selectively detecting an organic herbicide [2,4-dichlorophenoxyacetic acid (2,4-D)] in undiluted pure milks is described. First, it involves the synthesis of uniform "living" polymer particles via RAFT precipitation polymerization, their successive well-controlled grafting of a polymer shell labeled with red CdTe QDs (being inert to 2,4-D) and an MIP shell labeled with green 4-nitrobenzo[c][1,2,5]oxadiazole (NBD) units (showing fluorescence "light-up" upon binding 2,4-D) via surface-initiated RAFT polymerization, and final grafting of hydrophilic poly(N-isopropylacrylamide) brushes via an efficient coupling reaction (i.e., RAFT coupling chemistry). The resulting hydrophilic dual fluorescent MIP particles showed excellent photostability and reusability. They exhibited obvious analyte binding-induced "turn-on"-type ratiometric fluorescence (and color) change and high 2,4-D optosensing selectivity and sensitivity in pure bovine milk (with a detection limit of 0.13 µM). Moreover, they were directly applied to 2,4-D determination in undiluted pure goat milk with good recoveries (96.0-103.2%) and high accuracy (RSD = 1.5-5.5%), even in the presence of several analogues of 2,4-D. The general applicability of our strategy was also demonstrated. This study paves the way for efficiently developing various advanced MIP optosensors (of easily tunable structures and desired properties) highly promising in many bioanalytical applications.

13.
Ecotoxicol Environ Saf ; 156: 443-451, 2018 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-29605664

RESUMEN

Earthworms have the ability to take up heavy metals in soil and partition them in different subcellular compartments. In this study, we used a structural equation model (SEM) to investigate the two-step causal relationship between environmental availability (EA) and environmental bioavailability (EB) of heavy metals (Cd, Cu, Zn, and Pb), as reflected by their levels in soil fractions and in earthworms from field-contaminated areas in Southern China. In the SEM, the correlation between EA and EB reflected the bioavailability of Cd, Zn, and Pb. For Cd, the causal relationship between the latent variables EA and EB was reflected by DTPA fractions in soil as well as by earthworm internal and subcellular cytosol fractions. The extractable and oxidizable fractions of Zn in soil influenced Zn concentrations in the cytosol and debris. The DTPA and reducible Pb fractions were bioavailable to earthworm internal Pb concentrations and those in cytosol fractions. These results implied that the DTPA, extractable, oxidizable, or reducible fractions of different metals could be the bioavailable sources to earthworm internal metals and partitioned in their subcellular compartments.


Asunto(s)
Metales Pesados/análisis , Oligoquetos/metabolismo , Contaminantes del Suelo/análisis , Suelo/química , Animales , Disponibilidad Biológica , China , Monitoreo del Ambiente
14.
J Environ Sci (China) ; 73: 127-137, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30290861

RESUMEN

Earthworms have the ability to accumulate of heavy metals, however, there was few studies that addressed the metals in earthworm at subcellular levels in fields. The distributions of metals (Cd, Cu, Zn, and Pb) in subcellular fractions (cytosol, debris, and granules) of earthworm Metaphire californica were investigated. The relationship between soil metals and earthworms were analyzed to explain its high plasticity to inhabit in situ contaminated soil of Hunan Province, south China. The concentration of Cd in subcellular compartments showed the same pattern as Cu in the order of cytosol > debris > granules. The distribution of Zn and Pb in earthworms indicated a similar propensity for different subcellular fractions that ranked as granules > debris > cytosol for Zn, and granules > cytosol > debris for Pb. The internal metal concentrations in earthworms increased with the soil metals (p<0.05). Significant positive correlations were found between soil Cd and Cd concentrations in cytosol and debris (p<0.01). Moreover, the soil Pb concentration significantly influenced the Pb concentrations in cytosol and debris (p<0.01), similar to that of Cd. The soil Cu concentrations was only associated with the Cu in granules (p<0.05). Soil Zn concentrations correlated with the Zn concentrations in each subcellular fraction (p<0.05). Our results provide insights into the variations of metals partitioning in earthworms at subcellular levels and the relationships of soil metals, which could be one of the detoxification strategies to adapt the long-term contaminated environment.


Asunto(s)
Monitoreo del Ambiente , Metales Pesados/toxicidad , Oligoquetos/fisiología , Contaminantes del Suelo/toxicidad , Fracciones Subcelulares/fisiología , Animales , China , Metales Pesados/metabolismo , Contaminantes del Suelo/metabolismo
16.
Biomacromolecules ; 15(5): 1663-75, 2014 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-24666115

RESUMEN

A facile and highly efficient new approach (namely RAFT coupling chemistry) to obtain well-defined hydrophilic molecularly imprinted polymer (MIP) microspheres with excellent specific recognition ability toward small organic analytes in the real, undiluted biological samples is described. It involves the first synthesis of "living" MIP microspheres with surface-bound vinyl and dithioester groups via RAFT precipitation polymerization (RAFTPP) and their subsequent grafting of hydrophilic polymer brushes by the simple coupling reaction of hydrophilic macro-RAFT agents (i.e., hydrophilic polymers with a dithioester end group) with vinyl groups on the "living" MIP particles in the presence of a free radical initiator. The successful grafting of hydrophilic polymer brushes onto the obtained MIP particles was confirmed by SEM, FT-IR, static contact angle and water dispersion studies, elemental analyses, and template binding experiments. Well-defined MIP particles with densely grafted hydrophilic polymer brushes (∼1.8 chains/nm(2)) of desired chemical structures and molecular weights were readily obtained, which showed significantly improved surface hydrophilicity and could thus function properly in real biological media. The origin of the high grafting densities of the polymer brushes was clarified and the general applicability of the strategy was demonstrated. In particular, the well-defined characteristics of the resulting hydrophilic MIP particles allowed the first systematic study on the effects of various structural parameters of the grafted hydrophilic polymer brushes on their water-compatibility, which is of great importance for rationally designing more advanced real biological sample-compatible MIPs.


Asunto(s)
Microesferas , Impresión Molecular , Polímeros/química , Interacciones Hidrofóbicas e Hidrofílicas , Estructura Molecular , Tamaño de la Partícula , Polimerizacion , Polímeros/síntesis química , Propiedades de Superficie
17.
Int J Biol Macromol ; 262(Pt 2): 130043, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38340921

RESUMEN

Matrix metalloproteinase-2 (MMP-2)-responsive nanodrug vehicles have garnered significant attention as antitumor drug delivery systems due to the extensive research on matrix metalloproteinases (MMPs) within the tumor extracellular matrix (ECM). These nanodrug vehicles exhibit stable circulation in the bloodstream and accumulate specifically in tumors through various mechanisms. Upon reaching tumor tissues, their structures are degraded in response to MMP-2 within the ECM, resulting in drug release. This controlled drug release significantly increases drug concentration within tumors, thereby enhancing its antitumor efficacy while minimizing side effects on normal organs. This review provides an overview of MMP-2 characteristics, enzyme-sensitive materials, and current research progress regarding their application as MMP-2-responsive nanodrug delivery system for anti-tumor drugs, as well as considering their future research prospects. In conclusion, MMP-2-sensitive drug delivery carriers have a broad application in all kinds of nanodrug delivery systems and are expected to become one of the main means for the clinical development and application of nanodrug delivery systems in the future.


Asunto(s)
Nanopartículas , Neoplasias , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Sistemas de Liberación de Medicamentos/métodos , Neoplasias/tratamiento farmacológico , Portadores de Fármacos/uso terapéutico
18.
J Mol Recognit ; 26(5): 240-51, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23526776

RESUMEN

Bisphenol A (BPA) and propranolol-imprinted polymers have been prepared via both reversible addition-fragmentation chain transfer "bulk" polymerization (RAFTBP) and traditional radical "bulk" polymerization (TRBP) under similar reaction conditions, and their equilibrium binding properties were compared in detail for the first time. The chemical compositions, specific surface areas, equilibrium bindings, and selectivity of the obtained molecularly imprinted polymers (MIPs) were systematically characterized. The experimental results showed that the MIPs with molecular imprinting effects and quite fast binding kinetics could be readily prepared via RAFTBP, but they did not show improved template binding properties in comparison with those prepared via TRBP, which is in sharp contrast to many previous reports. This could be attributed to the heavily interrupted equilibrium between the dormant species and active radicals in the RAFT mechanism because of the occurrence of fast gelation during RAFTBP. The findings presented here strongly demonstrates that the application of controlled radical polymerizations (CRPs) in molecular imprinting does not always benefit the binding properties of the resultant MIPs, which is of significant importance for the rational use of CRPs in generating MIPs with improved properties.


Asunto(s)
Impresión Molecular/métodos , Polimerizacion , Polímeros/síntesis química , Compuestos de Bencidrilo/química , Cinética , Fenoles/química , Propranolol/química , Propiedades de Superficie
19.
J Colloid Interface Sci ; 644: 107-115, 2023 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-37105034

RESUMEN

Biocompatible metal-free carbon dots (CDs) with good photo-induced strong oxidation capacity in aqueous solutions are scarce for high-performance photocatalytic antibacterial and tumor therapy. In this work, we achieved effective visible light-induced cell death and antibacterial performance based on biocompatible metal-free CDs. The visible-light-induced reducing ability of the surface electron-withdrawing structure of the CDs allowed for the remaining photo-induced holes with high oxidation capacity to oxidize water molecules and generate hydroxyl radicals. Antibiotic-resistant bacteria were effectively inhibited by the CDs under xenon lamp irradiation with 450 nm long pass filter. Moreover, CD-based tumor photocatalytic therapy in mice was achieved using a xenon lamp with 450 nm long pass filter (0.3 W cm-2).


Asunto(s)
Carbono , Neoplasias , Animales , Ratones , Carbono/química , Luz , Antibacterianos/farmacología , Antibacterianos/química , Oxidación-Reducción , Metales , Agua
20.
Int J Nanomedicine ; 18: 3407-3428, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37377983

RESUMEN

Introduction: Hepatoma is the leading cause of death among liver diseases worldwide. Modern pharmacological studies suggest that some natural monomeric compounds have a significant effect on inhibiting tumor growth. However, poor stability and solubility, and side effects are the main factors limiting the clinical application of natural monomeric compounds. Methods: In this paper, drug-co-loaded nanoself-assemblies were selected as a delivery system to improve the chemical stability and solubility of Tanshinone II A and Glycyrrhetinic acid, and to produce a synergetic anti-hepatoma effect. Results: The study suggested that the drug co-loaded nanoself-assemblies showed high drug loading capacity, good physical and chemical stability, and controlled release. In vitro cell experiments verified that the drug-co-loaded nanoself-assemblies could increase the cellular uptake and cell inhibitory activity. In vivo studies verified that the drug co-loaded nanoself-assemblies could prolong the MRT0-∞, increase accumulation in tumor and liver tissues, and show strong synergistic anti-tumor effect and good bio-safety in H22 tumor-bearing mice. Conclusion: This work indicates that natural monomeric compounds co-loaded nanoself-assemblies would be a potential strategy for the treatment of hepatoma.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Ratones , Animales , Neoplasias Hepáticas/tratamiento farmacológico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/patología , Solubilidad , Línea Celular Tumoral
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