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1.
Langmuir ; 40(29): 14908-14921, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39001842

RESUMO

It is crucial to use simple methods to prepare stable polymeric micelles with multiple functions for cancer treatment. Herein, via a "bottom-up" strategy, we reported the fabrication of ß-CD-(PEOSMA-PCPTMA-PPEGMA)21 (ßPECP) unimolecular micelles that could simultaneously treat tumors and bacteria with chemotherapy and photodynamic therapy (PDT). The unimolecular micelles consisted of a 21-arm ß-cyclodextrin (ß-CD) core as a macromolecular initiator, photosensitizer eosin Y (EOS-Y) monomer EOSMA, anticancer drug camptothecin (CPT) monomer, and a hydrophilic shell PEGMA. Camptothecin monomer (CPTMA) could achieve controlled release of the CPT due to the presence of responsively broken disulfide bonds. PEGMA enhanced the biocompatibility of micelles as a hydrophilic shell. Two ßPECP with different lengths were synthesized by modulating reaction conditions and the proportion of monomers, which both were self-assembled to unimolecular micelles in water. ßPECP unimolecular micelles with higher EOS-Y/CPT content exhibited more excellent 1O2 production, in vitro drug release efficiency, higher cytotoxicity, and superior antibacterial activity. Also, we carried out simulations of the self-assembly and CPT release process of micelles, which agreed with the experiments. This nanosystem, which combines antimicrobial and antitumor functions, provides new ideas for bacteria-mediated tumor clinical chemoresistance.


Assuntos
Antineoplásicos , Micelas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Humanos , Antineoplásicos/química , Antineoplásicos/farmacologia , Pró-Fármacos/química , Pró-Fármacos/farmacologia , Antibacterianos/química , Antibacterianos/farmacologia , Animais , Camundongos , beta-Ciclodextrinas/química , Camptotecina/química , Camptotecina/farmacologia
2.
Small ; 19(46): e2304009, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37442787

RESUMO

Macrocyclic confinement-induced supramolecular luminescence materials have important application value in the fields of bio-sensing, cell imaging, and information anti-counterfeiting. Herein, a tunable multicolor lanthanide supramolecular assembly with white light emission is reported, which is constructed by co-assembly of cucurbit[7]uril (CB[7]) encapsulating naphthylimidazolium dicarboxylic acid (G1 )/Ln (Eu3+ /Tb3+ ) complex and carbon quantum dots (CD). Benefiting from the macrocyclic confinement effect of CB[7], the supramolecular assembly not only extends the fluorescence intensity of the lanthanide complex G1 /Tb3+ by 36 times, but also increases the quantum yield by 28 times and the fluorescence lifetime by 12 times. Furthermore, the CB[7]/G1 /Ln assembly can further co-assemble with CD and diarylethene derivatives (DAE) to realize the intelligently-regulated full-color spectrum including white light, which results from the competitive encapsulation of adamantylamine and CB[7], the change of pH, and photochromic DAE. The multi-level logic gate based on lanthanide supramolecular assembly is successfully applied in anti-counterfeiting system and information storage, providing an effective method for the research of new luminescent intelligent materials.

3.
Acc Chem Res ; 55(23): 3417-3429, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36380600

RESUMO

Hyaluronic acid (HA), which contains multiple carboxyl, hydroxyl, and acetylamino groups and is an agent that targets tumors, has drawn great attention in supramolecular diagnosis and treatment research. It can not only assemble directly with macrocyclic host-guest complexes through hydrogen bonding and electrostatic interactions but also can be modified with macrocyclic compounds or functional guest molecules by an amidation reaction and used for further assembly. Macrocycles play a main role in the construction of supramolecular drug carriers, targeted imaging agents, and hydrogels, such as cyclodextrins and cucurbit[n]urils, which can encapsulate photosensitizers, drugs, or other functional guest molecules via host-guest interactions. Therefore, the formed supramolecular assemblies can respond to various stimuli, such as enzymes, light, electricity, and magnetism for controlled drug delivery, enhance the luminescence intensity of the assembly, and improve drug loading capacity. In addition, the nanosupramolecular assembly formed with HA can also improve the biocompatibility of drugs, reduce drug toxicity and side effects, and enhance cell permeability; thus, the assembly has extensive application value in biomedical research. This Account mainly focuses on macrocyclic supramolecular assemblies based on HA, especially their biological applications and progress in the field, and these assemblies include (i) guest-modified HA, such as pyridinium-, adamantane-, peptide-, and other functional-group-modified HA, along with their cyclodextrin and cucurbit[n]uril assemblies; (ii) macrocycle-modified HA, such as HA modified with cyclodextrins and cucurbit[n]uril derivatives and their assembly with various guests; (iii) direct assembly between unmodified HA and cyclodextrin- or cucurbit[n]uril-based host-guest complexes. Particularly, we discussed the important role of macrocyclic host-guest complexes in HA-based supramolecular assembly, and the roles included improving the water solubility and efficacy of hydrophobic drugs, enhancing the luminescent intensity of assemblies, inducing room temperature phosphorescence and providing energy transfer systems, constructing multi-stimulus-responsive supramolecular assemblies, and in situ formation of hydrogels. Additionally, we believe that obtaining in-depth knowledge of these HA-based macrocyclic supramolecular assemblies and their biological applications encompasses many challenges regarding drug carriers, targeted imaging agents, wound healing, and biomedical soft materials and would certainly contribute to the rapid development of supramolecular diagnosis and treatment.


Assuntos
Ciclodextrinas , Compostos Macrocíclicos , Ácido Hialurônico , Ciclodextrinas/química , Hidrogéis/química , Portadores de Fármacos/química , Compostos Macrocíclicos/química , Materiais Biocompatíveis
4.
Phys Chem Chem Phys ; 25(17): 12458-12468, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37096448

RESUMO

Aiming at achieving the concurrent performances of high loading, well controlled release and active targeted delivery, folate (FA) modified dual pH/reduction-responsive mixed polymeric micelles were rationally assembled using FA-PEG-PDEAEMA and PEG-SS-PCL by dissipative particle dynamics (DPD) simulations. The optimized polymers PEG112-PDEAEMA40, FA-PEG112-PDEAEMA40, and PEG112-SS-PCL70 were synthesized and characterized using 1H NMR, FT-IR and GPC, and their mixed micelles were applied for doxorubicin (DOX) delivery. The drug loading capacity (LC) and encapsulation efficiency (EE) values of the MIX1 (FA-PEG112-PDEAEMA40/PEG112-SS-PCL70) at a DOX/polymer feeding ratio of 15 mg/30 mg were 20.22% and 50.69%, which were higher than those of single polymer micelles and MIX2 (PEG112-PDEAEMA40/PEG112-SS-PCL70). Particle size distributions, mesoscopic morphologies, DPD simulations and in vitro drug release profiles all confirmed the well-controlled release performance of the DOX-loaded micelles formed by MIX1: slow DOX release with a cumulative release of 20.46% in the neutral environment and accelerated release with a cumulative release of 74.20% at pH 5.0 + 10 mM DTT within 120 h, which were similar to those of MIX2. Cytotoxicity assay found that both MIX1 and MIX2 blank micelles were biocompatible, and a superior inhibitory effect of the FA-modified DOX-loaded micelles MIX1 on HepG2 cells was found compared to that of free DOX and non-FA-modified DOX-loaded micelles MIX2. All of these confirmed the superiority of MIX1 micelles with high loading capacity, well controlled release, and enhanced inhibitory effects on HepG2 cells, which might be a prospective candidate for anticancer drug delivery.


Assuntos
Ácido Fólico , Micelas , Preparações de Ação Retardada , Ácido Fólico/química , Espectroscopia de Infravermelho com Transformada de Fourier , Doxorrubicina/química , Polietilenoglicóis/química , Polímeros/química , Concentração de Íons de Hidrogênio , Portadores de Fármacos/química , Sobrevivência Celular
5.
Plant J ; 106(5): 1219-1232, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33595908

RESUMO

Loss of chlorophyll (Chl) is a hallmark of leaf senescence, which may be regulated by Chl catabolic genes, including NON-YELLOW COLORING 1 (NYC1)-like (NOL). The objective of this study was to determine molecular factors and metabolic pathways underlying NOL regulation of leaf senescence in perennial grass species. LpNOL was cloned from perennial ryegrass (Lolium perenne L.) and found to be highly expressed in senescent leaves. Transient overexpression of LpNOL accelerated leaf senescence and Chl b degradation in Nicotiana benthamiana. LpNOL RNA interference (NOLi) in perennial ryegrass not only significantly blocked Chl degradation in senescent leaves, but also delayed initiation and progression of leaf senescence. This study found that NOL, in addition to functioning as a Chl b reductase, could enact the functional stay-green phenotype in perennial grass species, as manifested by increased photosynthetic activities in NOLi plants. Comparative transcriptomic analysis revealed that NOL-mediated functional stay-green in perennial ryegrass was mainly achieved through the modulation of Chl catabolism, light harvesting for photosynthesis, photorespiration, cytochrome respiration, carbohydrate catabolism, oxidative detoxification, and abscisic acid biosynthesis and signaling pathways.


Assuntos
Oxirredutases do Álcool/metabolismo , Clorofila/metabolismo , Lolium/genética , Redes e Vias Metabólicas/genética , Fotossíntese/genética , Transcriptoma , Ácido Abscísico/metabolismo , Oxirredutases do Álcool/genética , Expressão Gênica , Perfilação da Expressão Gênica , Lolium/enzimologia , Lolium/fisiologia , Oxirredução , Oxigênio/metabolismo , Fenótipo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/enzimologia , Folhas de Planta/genética , Folhas de Planta/fisiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Transdução de Sinais , Fatores de Tempo , Nicotiana/genética , Nicotiana/fisiologia
6.
Soft Matter ; 15(4): 546-558, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30644512

RESUMO

High micellar stability and well-performed drug loading and release are two conflicting factors for unimolecular micelles as an ideal drug delivery system. Achieving the formation of unimolecular micelles with short hydrophilic blocks is a challenging and promising approach to solve this bottleneck and limitation of current unimolecular micelle systems. In this work, dissipative particle dynamics (DPD) simulation is used to study the synergetic effect of crosslinking and electrostatic repulsion on stability of unimolecular micelles and to analyze the micro-mechanism and factors influencing this synergetic stabilization strategy. The strategy can generate unimolecular micelles with extremely high stability for various supramolecular polymers with short hydrophilic chains. Protonation of DEAEMA blocks leads to a large improvement in micellar hydrophilicity. The protonated middle layer further shrinks through crosslinking to produce the largest charge density, enlarging the electrostatic repulsion between colloidal particles. Additionally, the crosslinking and protonation treatment maximizes the extension degree of hydrophilic EO segments due to the increasing steric hindrance and poor compatibility between DEAHEMA and EO blocks. In this study, the relation between shrinkage degree of hydrophobic cores and stability of unimolecular micelles is first reported. The above-mentioned transition of micellar structures and properties results in the maximum degree of core shrinkage (Rg of MMA blocks) corresponding to the high stability of unimolecular micelles. Further study shows that the increasing cyclization degree, the mode of end cyclization, and the crosslinking and electrostatic repulsion of the middle layer all exert favorable effects on the stability of unimolecular micelles due to controlled shrinkage of hydrophobic cores.


Assuntos
Portadores de Fármacos/química , Interações Hidrofóbicas e Hidrofílicas , Micelas , Modelos Moleculares , Polímeros/química , Concentração de Íons de Hidrogênio , Conformação Molecular , Solventes/química , Eletricidade Estática , Propriedades de Superfície
7.
BMC Pregnancy Childbirth ; 19(1): 105, 2019 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-30922244

RESUMO

BACKGROUND: Maternal body mass index is linked to short- and long-term unfavorable health outcomes both for child and mother. We conducted a systematic review and meta-analysis of population-based cohort studies to evaluate maternal BMI and the risk of harmful neonatal outcomes in China. METHODS: Six databases identified 2454 articles; 46 met the inclusion criteria for this study. The dichotomous data on maternal BMI and harmful neonatal outcomes were extracted. Pooled statistics (odds ratios, ORs) were derived from Stata/SE, ver. 12.0. Sensitivity analyses assessed the robustness of the results. Meta-regression and subgroup meta-analyses explored heterogeneity. RESULTS: The meta-analysis revealed that compared with normal BMI, high maternal BMI is associated with fetal overgrowth, defined as macrosomia ≥4000 g (OR 1.91, 95% CI 1.75-2.09); birth weight ≥ 90% for gestational age (OR 1.88, 95% CI 1.64-2.15); and increased risk of premature birth (OR 1.38, 95% CI 1.25-2.52) and neonatal asphyxia (OR 1.74, 95% CI 1.39-2.17). Maternal underweight increased the risk of low birth weight (OR 1.61, 95% CI 1.33-1.93) and small for gestational age (OR 1.75, 95% CI 1.51-2.02). CONCLUSIONS: Raised as well as low pre-pregnancy BMI is associated with adverse neonatal outcomes. Management of weight during pregnancy might help reduce their adverse neonatal outcomes in future intervention studies or programmes.


Assuntos
Índice de Massa Corporal , Obesidade/fisiopatologia , Complicações na Gravidez/fisiopatologia , Resultado da Gravidez/epidemiologia , Adulto , Peso ao Nascer , China/epidemiologia , Feminino , Macrossomia Fetal/etiologia , Ganho de Peso na Gestação , Humanos , Recém-Nascido de Baixo Peso , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional , Obesidade/complicações , Gravidez , Complicações na Gravidez/etiologia , Fatores de Risco
8.
Public Health Nutr ; 21(6): 1123-1130, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29208067

RESUMO

OBJECTIVE: To investigate caregiver type as a potential moderating effect in the relationship between feeding style and weight status among Chinese pre-school children. DESIGN: Cross-sectional data collected with the Caregiver's Feeding Style Questionnaire (CFSQ), anthropometric data, childcare and sociodemographic information. SETTING: Shenyang, China. SUBJECTS: Caregiver-child dyads (n 857). RESULTS: After controlling for confounders, authoritarian feeding style was associated with a 0·30 lower BMI Z-score. Fathers as primary caregivers were related to lower BMI Z-score (ß=-0·66), while grandparents as main caregivers were associated with higher BMI Z-score (ß=0·66) after adjusting for covariates. Mothers buffered the relationship between authoritarian (ß=0·50, 95 % CI 0·04, 0·95) or indulgent (ß=-0·60, 95 % CI -1·06, -0·14) feeding styles and BMI Z-score. Grandparents strengthened the trend that indulgent feeding style was related to higher BMI Z-score (ß=0·54, 95 % CI 0·01, 1·08). CONCLUSIONS: The results of independent and interactive effects of specific feeding styles and caregiver types had different influences on child BMI Z-scores. Longitudinal investigations are needed to evaluate the effect of fathers' and grandparents' feeding on their children's nutrition and weight status.


Assuntos
Cuidadores/estatística & dados numéricos , Dieta/estatística & dados numéricos , Comportamento Alimentar/fisiologia , Pré-Escolar , China/epidemiologia , Estudos Transversais , Humanos , Modelos Estatísticos , Sobrepeso/epidemiologia , Magreza/epidemiologia
9.
Biomacromolecules ; 18(12): 3869-3880, 2017 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-29032674

RESUMO

Current research is mainly trending toward addressing the development of multifunctional nanocarriers that could precisely reach disease sites, release drugs in a controlled-manner, and act as an imaging agent for both diagnosis and targeted therapy. In this study, a pH-sensitive theranostic nanoplatform as a promising dual-functional nanovector for tumor therapy and computed tomography (CT) imaging was developed. The 21-arm star-like triblock polymer of ß-cyclodextrin-{poly(ε-caprolactone)-poly(2-aminoethyl methacrylate)-poly[poly(ethylene glycol) methyl ether methacrylate]}21 [ß-CD-(PCL-PAEMA-PPEGMA)21] with stable unimolecular micelles formed in aqueous solution was first synthesized by combined ROP with ARGET ATRP techniques and then was used as a template for fabricating gold nanoparticles (AuNPs) with uniform sizes and excellent colloidal stability in situ followed by the encapsulation of doxorubicin (DOX) with maximum entrapment efficiency up to 60% to generate the final product ß-CD-(PCL-PAEMA-PPEGMA)21/AuNPs/DOX. Furthermore, dissipative particle dynamics (DPD) simulations revealed further details of the formation process of unimolecular micelles and the morphologies and distributions of AuNPs and DOX. Almost 80% of DOX was released in 120 h in an acidic tumoral environment in an in vitro drug release experiment, and the experiments both in vitro and in vivo demonstrated the fact that ß-CD-(PCL-PAEMA-PPEGMA)21/AuNPs/DOX exhibited similar antitumor efficacy to free DOX and effective CT imaging performance. Therefore, we believe this structurally stable unimolecular micelle-based nanoplatform synergistically integrated with anticancer drug delivery and CT imaging capabilities hold great promise for future cancer theranostics.


Assuntos
Doxorrubicina/química , Doxorrubicina/farmacologia , Ouro/química , Nanopartículas Metálicas/química , Neoplasias/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Sistemas de Liberação de Medicamentos/métodos , Células Hep G2 , Humanos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Micelas , Tamanho da Partícula , Poliésteres/química , Polietilenoglicóis/química , Polímeros/química , Ácidos Polimetacrílicos , Nanomedicina Teranóstica/métodos , Tomografia Computadorizada por Raios X/métodos
10.
Phys Chem Chem Phys ; 18(38): 26519-26529, 2016 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-27711540

RESUMO

Unimolecular polymeric micelles have several features, such as thermodynamic stability, small particle size, biocompatibility, and the ability to internalize hydrophobic molecules. These micelles have recently attracted significant attention in various applications, such as nano-reactors, catalysis, and drug delivery. However, few attempts have explored the formation mechanisms and conditions of unimolecular micelles due to limited experimental techniques. In this study, a unimolecular micelle system formed from ß-cyclodextrin-graft-{poly(lactide)-block-poly(2-(dimethylamino) ethyl multimethacrylate)-block-poly[oligo (2-ethyl-2-oxazoline) methacrylate]} ß-CD-g-(PLA-b-PDMAEMA-b-PEtOxMA) star-like block copolymers in aqueous media was investigated by dissipative particle dynamics (DPD) to explore the formation process of unimolecular micelles. The simulation results showed that using longer hydrophobic or pH-sensitive chains, shorter hydrophilic backbones, smaller hydrophilic side chain grafting density, and fewer polymer arms resulted in micellar aggregation. Furthermore, this unimolecular polymeric micelle could be used for encapsulating gold nanoparticles, whose mesoscopic structure was also explored. The gold nanoparticles tended to distribute in the middle layer formed by PDMAEMA, and the unimolecular micelles were capable of impeding gold nanoparticle aggregation. This study could help understand the formation mechanism of unimolecular micelles formed from star-like block copolymers in dilute solutions and offer a theoretical guide to the design and preparation of promising unimolecular polymeric micelles with targeting properties.

11.
J Cogn Neurosci ; 27(10): 1957-67, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26042501

RESUMO

The medial prefrontal cortex (mPFC) is consistently implicated in the network supporting autobiographical memory. Whereas more posterior regions in this network have been related to specific processes, such as the generation of visuospatial imagery or the association of items and contexts, the functional contribution of the mPFC remains unclear. However, the involvement of mPFC in estimation of value during decision-making suggests that it might play a similar role in memory. We investigated whether mPFC activity reflects the subjective value of elements in imagined scenarios. Participants in an MRI scanner imagined scenarios comprising a spatial context, a physiological state of need (e.g., thirst), and two items that could be congruent (e.g., drink) or incongruent (e.g., food) with the state of need. Memory for the scenarios was tested outside the scanner. Our manipulation of subjective value by imagined need was verified by increased subjective ratings of value for congruent items and improved subsequent memory for them. Consistent with our hypothesis, fMRI signal in mPFC reflected the modulation of an item's subjective value by the imagined physiological state, suggesting the mPFC selectively tracked subjective value within our imagination paradigm. Further analyses showed uncorrected effects in non-mPFC regions, including increased activity in the insula when imagining states of need, the caudate nucleus when imagining congruent items, and the anterior hippocampus/amygdala when imagining subsequently remembered items. We therefore provide evidence that the mPFC plays a role in constructing the subjective value of the components of imagined scenarios and thus potentially in reconstructing the value of components of autobiographical recollection.


Assuntos
Encéfalo/fisiologia , Imaginação/fisiologia , Imageamento por Ressonância Magnética/métodos , Memória Episódica , Córtex Pré-Frontal/fisiologia , Adulto , Feminino , Humanos , Masculino , Motivação , Adulto Jovem
12.
Am J Case Rep ; 25: e943947, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38935578

RESUMO

BACKGROUND Spinal cord arteriovenous fistula that only manifests as lower back pain is easily misdiagnosed as myofasciitis, lumbar spondylosis, and other diseases, and incorrect treatment such as glucocorticoid blockade might be given, leading to worsening of the condition. CASE REPORT We analyze the clinical characteristics of a patient with spinal dural arteriovenous fistula who presented with chronic-onset low back pain. A patient with spinal dural arteriovenous fistula presented with chronic-onset low back pain as the only symptom, and was misdiagnosed as having myofasciitis. We assessed the paraclinical data, clinical reasoning, and course of treatment. The patient was an elderly man with low back pain for 1 year. He was diagnosed with myofasciitis in a local hospital and received local blocking treatment using glucocorticoid, and left lower-limb weakness appeared after that. After he was admitted to our hospital, enhanced thoracic and lumbar magnetic resonance imaging and selective spinal angiography were performed, and the results indicated the diagnosis of spinal dural arteriovenous fistula. After surgical treatment, the low back pain and lower-limb weakness were alleviated, and the patient is still under follow-up. CONCLUSIONS The possibility of spinal dural arteriovenous fistula should not be overlooked among patients with chronic low back pain, and caution should be taken when using glucocorticoids for treatment of chronic low back pain.


Assuntos
Malformações Vasculares do Sistema Nervoso Central , Dor Lombar , Humanos , Masculino , Dor Lombar/etiologia , Malformações Vasculares do Sistema Nervoso Central/complicações , Malformações Vasculares do Sistema Nervoso Central/terapia , Malformações Vasculares do Sistema Nervoso Central/diagnóstico , Idoso , Imageamento por Ressonância Magnética , Diagnóstico Diferencial
13.
RSC Adv ; 14(28): 20130-20144, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38915333

RESUMO

Multidrug-resistant bacteria resulting from the abuse and overuse of antibiotics have become a huge crisis in global public health security. Therefore, it is urgently needed to develop new antibacterial drugs with unique mechanisms of action. As a versatile moiety, morpholine has been widely employed to enhance the potency of numerous bioactive molecules. In this study, a series of ruthenium-based antibacterial agents modified with the morpholine moiety were designed and characterized, aiming to obtain a promising metalloantibiotic with a multitarget mechanism. Antibacterial activity screening demonstrated that the most active complex Ru(ii)-3 exhibited the strongest potency against Staphylococcus aureus (S. aureus) with an MIC value of only 0.78 µg mL-1, which is better than most clinically used antibiotics. Notably, Ru(ii)-3 not only possessed excellent bactericidal efficacy, but could also overcome bacterial resistance. Importantly, Ru(ii)-3 very efficiently removed biofilms produced by bacteria, inhibited the secretion of bacterial exotoxins, and enhanced the activity of many existing antibiotics. The results of mechanism studies confirmed that Ru(ii)-3 could destroy the bacterial membrane and induce ROS production in bacteria. Furthermore, animal infection models confirmed that Ru(ii)-3 showed significant anti-infective activity in vivo. Overall, this work demonstrated that a morpholine-modified ruthenium-based agent is a promising antibiotic candidate in tackling the crisis of drug-resistant bacteria.

14.
Int J Biol Macromol ; 259(Pt 2): 129266, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199532

RESUMO

Considering the astonishing prevalence of localized pain affecting billions of patients worldwide, the development of advanced analgesic formulations or delivery systems to achieve clinical applicability is of great significance. In this study, an integrated PDA-based LiH@PDA@Ag@PAA@Gelatin system was designed for sustained delivery of lidocaine hydrochloride (LiH). By optimizing the preparation process and formulation of the hydrogel, the hydrogel exhibited superior mechanical properties, reversibility, adhesion strength, and self-healing attributes. Moreover, PDA@Ag nanoparticles were evenly dispersed within the hydrogel, and the optimized PDA@Ag@PAA@Gelatin showed a higher photothermal conversion efficiency than that of pure PDA. Importantly, LiH@PDA@Ag@PAA@Gelatin could effectively capture and eradicate bacteria through the synergistic interaction between near-infrared (NIR), PDA, Ag and LiH. In vitro and in vivo tests demonstrated that LiH@PDA@Ag@PAA@Gelatin exhibited higher drug delivery efficiency compared to commercial lidocaine patches. By evaluating the mechanical pain withdrawal threshold of the spared nerve injury (SNI) model in rats, it was proven that LiH@PDA@Ag@PAA@Gelatin enhanced and prolonged the analgesic effect of LiH. Furthermore, LiH@PDA@Ag@PAA@Gelatin induced by NIR possessed excellent on-demand photothermal analgesic ability. Therefore, this study develops a convenient method for preparing localized analgesic hydrogel patches, providing an important step towards advancing PDA-based on-demand pain relief applications.


Assuntos
Analgesia , Indóis , Nanopartículas Metálicas , Polímeros , Humanos , Ratos , Animais , Adesivos , Lidocaína/farmacologia , Lidocaína/uso terapêutico , Hidrogéis/farmacologia , Gelatina , Prata , Dor/tratamento farmacológico , Analgésicos/farmacologia , Analgésicos/uso terapêutico
15.
Int J Biol Macromol ; 271(Pt 1): 132499, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38777014

RESUMO

In light of the depletion of petrochemical resources and increase in environmental pollution, there has been a significant focus on utilizing natural biomass, specifically lignin, to develop sustainable and functional materials. This research presents the development of a lignin-based polyurethane (DLPU) with photothermal-responsiveness by incorporating lignin and oxime-carbamate bonds into polyurethane network. The abundant hydrogen bonds between lignin and the polyurethane matrix, along with its cross-linked structure, contribute to DLPU's excellent mechanical strength (30.2 MPa) and toughness (118.7 MJ·m-3). Moreover, the excellent photothermal conversion ability of DLPU (54.4 %) activates dynamic reversible behavior of oxime-carbamate bonds and hydrogen bonds, thereby endowing DLPU with exceptional self-healing performance. After 15 min of near-infrared irradiation, DLPU achieves self-healing efficiencies of 96.0 % for tensile strength and 96.3 % for elongation at break. Additionally, DLPU exhibits photocontrolled solid-state plasticity as well as an excellent phototriggered shape-memory effect (70 s), with shape fixity and recovery ratios reaching 98.8 % and 95.3 %, respectively. By exploiting the spatial controllability and photothermal-responsiveness of DLPU, we demonstrate multi-dimensional responsive materials with self-healing and shape-shifting properties. This work not only promotes the development of multi-functional polyurethanes but also provides a pathway for the high-value utilization of lignin.


Assuntos
Lignina , Poliuretanos , Poliuretanos/química , Lignina/química , Resistência à Tração , Temperatura , Ligação de Hidrogênio , Fenômenos Mecânicos
16.
Adv Sci (Weinh) ; : e2401983, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38894574

RESUMO

Physical unclonable function (PUF) is attractive in modern encryption technologies. Addressing the disadvantage of slow data storage/authentication in optical PUF is paramount for practical applications but remains an on-going challenge. Here, a highly efficient PUF strategy based on random structural color domains (SCDs) of cellulose nanocrystal (CNC) is proposed for the first time, combing with hyperspectral imaging system (HIS) for ultrafast storage and authentication. By controlling the growth and fusion behavior of the tactoids of CNC, the SCDs display an irregular and random distribution of colors, shapes, sizes, and reflectance spectra, which grant unique and inherent fingerprint-like characteristics that are non-duplicated. Based on images and spectra, these fingerprint features are used to develop two sets of PUF key generation methods, which can be respectively authenticated at the user-end and the manufacturer-front-end that achieving a high coding capacity of at least 22304. Notably, the use of HIS greatly shortens the time of key reading and generation (≈5 s for recording, 0.5-0.7 s for authentication). This new optical PUF labels can not only solve slow data storage and complicated authentication in optical PUF, but also impulse the development of CNC in industrial applications by reducing color uniformity requirement.

17.
PeerJ ; 12: e17521, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38903881

RESUMO

Background: Acute respiratory distress syndrome (ARDS) is a severe complication that can lead to fatalities in multiple trauma patients. Nevertheless, the incidence rate and early prediction of ARDS among multiple trauma patients residing in high-altitude areas remain unknown. Methods: This study included a total of 168 multiple trauma patients who received treatment at Shigatse People's Hospital Intensive Care Unit (ICU) between January 1, 2019 and December 31, 2021. The clinical characteristics of the patients and the incidence rate of ARDS were assessed. Univariable and multivariable logistic regression models were employed to identify potential risk factors for ARDS, and the predictive effects of these risk factors were analyzed. Results: In the high-altitude area, the incidence of ARDS among multiple trauma patients was 37.5% (63/168), with a hospital mortality rate of 16.1% (27/168). Injury Severity Score (ISS) and thoracic injuries were identified as significant predictors for ARDS using the logistic regression model, with an area under the curve (AUC) of 0.75 and 0.75, respectively. Furthermore, a novel predictive risk score combining ISS and thoracic injuries demonstrated improved predictive ability, achieving an AUC of 0.82. Conclusions: This study presents the incidence of ARDS in multiple trauma patients residing in the Tibetan region, and identifies two critical predictive factors along with a risk score for early prediction of ARDS. These findings have the potential to enhance clinicians' ability to accurately assess the risk of ARDS and proactively prevent its onset.


Assuntos
Altitude , Traumatismo Múltiplo , Síndrome do Desconforto Respiratório , Humanos , Síndrome do Desconforto Respiratório/mortalidade , Síndrome do Desconforto Respiratório/epidemiologia , Masculino , Feminino , Incidência , Estudos Retrospectivos , Pessoa de Meia-Idade , Adulto , Fatores de Risco , Traumatismo Múltiplo/mortalidade , Traumatismo Múltiplo/epidemiologia , Traumatismo Múltiplo/complicações , Mortalidade Hospitalar , Escala de Gravidade do Ferimento , China/epidemiologia , Traumatismos Torácicos/mortalidade , Traumatismos Torácicos/epidemiologia , Traumatismos Torácicos/complicações , Unidades de Terapia Intensiva
18.
Eur J Med Chem ; 270: 116378, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604098

RESUMO

Infections caused by Staphylococcus aureus (S. aureus) are increasing difficult to treat because this pathogen is easily resistant to antibiotics. However, the development of novel antibacterial agents with high antimicrobial activity and low frequency of resistance remains a huge challenge. Here, building on the coupling strategy, an adamantane moiety was linked to the membrane-active Ru-based structure and then developed three novel metalloantibiotics: [Ru(bpy)2(L)](PF6)2 (Ru1) (bpy = 2,2-bipyridine, L = amantadine modified ligand), [Ru(dmb)2(L)](PF6)2 (Ru2) (dmb = 4,4'-dimethyl-2,2'-bipyridine) and [Ru(dpa)2(L)](PF6)2 (Ru3), (dpa = 2,2'-dipyridylamine). Notably, complex Ru1 was identified to be the best candidate agent, showing greater efficacy against S. aureus than most of clinical antibiotics and low resistance frequencies. Mechanism studies demonstrated that Ru1 could not only increase the permeability of bacterial cell membrane and then caused the leakage of bacterial contents, but also promoted the production of reactive oxygen species (ROS) in bacteria. Importantly, complex Ru1 inhibited the biofilm formation, exotoxin secretion and increased the potency of some clinical used antibiotics. In addition, Ru1 showed low toxic in vivo and excellent anti-infective efficacy in two animal infection model. Thus, Ru-based metalloantibiotic bearing adamantane moiety are promising antibacterial agents, providing a certain research basis for the future antibiotics research.


Assuntos
Adamantano , Complexos de Coordenação , Rutênio , Animais , Antibacterianos/farmacologia , Adamantano/farmacologia , Staphylococcus aureus , Rutênio/farmacologia , Rutênio/química , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química
19.
Guang Pu Xue Yu Guang Pu Fen Xi ; 33(1): 23-6, 2013 Jan.
Artigo em Zh | MEDLINE | ID: mdl-23586216

RESUMO

In the present paper, AlF3-YbF3 : Er3+ was prepared by high temperature solid phase reaction, and the concentration effect of Er3+ on luminous intensity of phosphors was studied. The crystal structures of the phosphors were characterized by means of X-ray diffraction (XRD), and the upconversion luminescence properties of phosphor were studied by fluorescence emission spectra. Upon 980 nm excitation, when the Er3+ concentration was fixed to be 0.7 mol%, the maximum red emission intensities can be obtained in the sample. Furthermore, the research results showed that the fitted slope for red transition emission was 2.24, indicating that red emission is due to a two-photon excitation process.

20.
Chem Sci ; 14(23): 6457-6466, 2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37325139

RESUMO

A photo-responsive full-color lanthanide supramolecular switch was constructed from a synthetic 2,6-pyridine dicarboxylic acid (DPA)-modified pillar[5]arene (H) complexing with lanthanide ion (Ln3+ = Tb3+ and Eu3+) and dicationic diarylethene derivative (G1) through a noncovalent supramolecular assembly. Benefiting from the strong complexation between DPA and Ln3+ with a 3 : 1 stoichiometric ratio, the supramolecular complex H/Ln3+ presented an emerging lanthanide emission in the aqueous and organic phase. Subsequently, a network supramolecular polymer was formed by H/Ln3+ further encapsulating dicationic G1via the hydrophobic cavity of pillar[5]arene, which greatly contributed to the increased emission intensity and lifetime, and also resulted in the formation of a lanthanide supramolecular light switch. Moreover, full-color luminescence, especially white light emission, was achieved in aqueous (CIE: 0.31, 0.32) and dichloromethane (CIE: 0.31, 0.33) solutions by the adjustment of different ratios of Tb3+ and Eu3+. Notably, the photo-reversible luminescence properties of the assembly were tuned via alternant UV/vis light irradiation due to the conformation-dependent photochromic energy transfer between the lanthanide and the open/closed-ring of diarylethene. Ultimately, the prepared lanthanide supramolecular switch was successfully applied to anti-counterfeiting through the use of intelligent multicolored writing inks, and presents new opportunities for the design of advanced stimuli-responsive on-demand color tuning with lanthanide luminescent materials.

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