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1.
Ann Intern Med ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38976882

RESUMO

BACKGROUND: Methadone maintenance treatment (MMT) is effective for managing opioid use disorder, but adverse effects mean that optimal therapy occurs with the lowest dose that controls opioid craving. OBJECTIVE: To assess the efficacy of acupuncture versus sham acupuncture on methadone dose reduction. DESIGN: Multicenter, 2-group, randomized, sham-controlled trial. (Chinese Clinical Trial Registry: ChiCTR2200058123). SETTING: 6 MMT clinics in China. PARTICIPANTS: Adults aged 65 years or younger with opioid use disorder who attended clinic daily and had been using MMT for at least 6 weeks. INTERVENTION: Acupuncture or sham acupuncture 3 times a week for 8 weeks. MEASUREMENTS: The 2 primary outcomes were the proportion of participants who achieved a reduction in methadone dose of 20% or more compared with baseline and opioid craving, which was measured by the change from baseline on a 100-mm visual analogue scale (VAS). RESULTS: Of 118 eligible participants, 60 were randomly assigned to acupuncture and 58 were randomly assigned to sham acupuncture (2 did not receive acupuncture). At week 8, more patients reduced their methadone dose 20% or more with acupuncture than with sham acupuncture (37 [62%] vs. 16 [29%]; risk difference, 32% [97.5% CI, 13% to 52%]; P < 0.001). In addition, acupuncture was more effective in decreasing opioid craving than sham acupuncture with a mean difference of -11.7 mm VAS (CI, -18.7 to -4.8 mm; P < 0.001). No serious adverse events occurred. There were no notable differences between study groups when participants were asked which type of acupuncture they received. LIMITATION: Fixed acupuncture protocol limited personalization and only 12 weeks of follow-up after stopping acupuncture. CONCLUSION: Eight weeks of acupuncture were superior to sham acupuncture in reducing methadone dose and decreasing opioid craving. PRIMARY FUNDING SOURCE: National Natural Science Foundation of China.

2.
Nano Lett ; 24(8): 2520-2528, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38359360

RESUMO

Enzymatic catalysis presents an eco-friendly, energy-efficient method for lignin degradation. However, challenges arise due to the inherent incompatibility between enzymes and native lignin. In this work, we introduce a supramolecular catalyst composed of fluorenyl-modified amino acids and Cu2+, designed based on the aromatic stacking of the fluorenyl group, which can operate in ionic liquid environments suitable for the dissolution of native lignin. Amino acids and halide anions of ionic liquids shape the copper site's coordination sphere, showcasing remarkable catechol oxidase-mimetic activity. The catalyst exhibits thermophilic property, and maintains oxidative activity up to 75 °C, which allows the catalyzed degradation of the as-dissolved native lignin with high efficiency even without assistance of the electron mediator. In contrast, at this condition, the native copper-dependent oxidase completely lost its activity. This catalyst with superior stability and activity offer promise for sustainable lignin valorization through biocatalytic routes compatible with ionic liquid pretreatment, addressing limitations in native enzymes for industrially relevant conditions.


Assuntos
Líquidos Iônicos , Líquidos Iônicos/química , Lignina/química , Cobre , Oxirredutases , Catálise , Aminoácidos
3.
Nano Lett ; 23(24): 11461-11468, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38079506

RESUMO

Challenges persist in replicating enzyme-like active sites with functional group arrangements in supramolecular catalysis. In this study, we present a supramolecular material comprising Fmoc-modified histidine and copper. We also investigated the impact of noncanonical amino acids (δmH and εmH), isomers of histidine, on the catalytic process. The Fmoc-δmH-based nanoassembly exhibits an approximately 15-fold increase in oxidative activity and an ∼50-fold increase in hydrolytic activity compared to Fmoc-εmH (kcat/Km). This distinction arises from differences in basicity and ligation properties between the ε- and δ-nitrogen of histidine. The addition of guanosine monophosphate further enhances the oxidative activity of the histidine- and methylated histidine-based catalysts. The Fmoc-δmH/Cu2+-based nanoassembly catalyzes the oxidation/hydrolysis cascade of 2',7'-dichlorofluorescein diacetate, benefiting from the synergistic effect between the copper center and the nonligating ε-nitrogen of histidine. These findings advance the biomimetic catalyst design and provide insights into the mechanistic role of essential residues in natural systems.


Assuntos
Biomimética , Histidina , Catálise , Cobre , Histidina/química , Hidrólise , Nitrogênio , Estresse Oxidativo
4.
BMC Pregnancy Childbirth ; 23(1): 779, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37950186

RESUMO

BACKGROUND: The purpose of this study was to construct a preterm birth prediction model based on electronic health records and to provide a reference for preterm birth prediction in the future. METHODS: This was a cross-sectional design. The risk factors for the outcomes of preterm birth were assessed by multifactor logistic regression analysis. In this study, a logical regression model, decision tree, Naive Bayes, support vector machine, and AdaBoost are used to construct the prediction model. Accuracy, recall, precision, F1 value, and receiver operating characteristic curve, were used to evaluate the prediction performance of the model, and the clinical application of the model was verified. RESULTS: A total of 5411 participants were included and were used for model construction. AdaBoost model has the best prediction ability among the five models. The accuracy of the model for the prediction of "non-preterm birth" was the highest, reaching 100%, and that of "preterm birth" was 72.73%. CONCLUSIONS: By constructing a preterm birth prediction model based on electronic health records, we believe that machine algorithms have great potential for preterm birth identification. However, more relevant studies are needed before its application in the clinic.


Assuntos
Nascimento Prematuro , Feminino , Humanos , Recém-Nascido , Nascimento Prematuro/epidemiologia , Teorema de Bayes , Estudos Transversais , Algoritmos , Aprendizado de Máquina
5.
Angew Chem Int Ed Engl ; 62(36): e202305677, 2023 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-37204428

RESUMO

Designing sustainable materials with tunable mechanical properties, intrinsic degradability, and recyclability from renewable biomass through a mild process has become vital in polymer science. Traditional phenolic resins are generally considered to be not degradable or recyclable. Here we report the design and synthesis of linear and network structured phenolic polymers using facile polycondensation between natural aldehyde-bearing phenolic compounds and polymercaptans. Linear phenolic products are amorphous with Tg between -9 °C and 12 °C. Cross-linked networks from vanillin and its di-aldehyde derivative exhibited excellent mechanical strength between 6-64 MPa. The connecting dithioacetals are associatively adaptable strong bonds and susceptible to degradation in oxidative conditions to regenerate vanillin. These results highlight the potential of biobased sustainable phenolic polymers with recyclability and selective degradation, as a complement to the traditional phenol-formaldehyde resins.

6.
Chem Biodivers ; 19(4): e202100746, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35233905

RESUMO

Three series of secondary ammonium chloride from turpentine were synthesized and evaluated as botanical herbicides. The preemergence herbicidal activities against ryegrass (Loliun multiflorum) and barnyard grass (Echinochloa crus-galli) were investigated using water as the only solvent. Their toxicity was evaluated by cytotoxicity assays. Preliminary results demonstrated that the herbicidal performance of the prepared salts was similar or much higher than that of corresponding secondary amines and even commercial herbicide glyphosate. Promisingly, compound 14e containing a cyclohexyl-substituted p-menthene skeleton with an IC50 value of 0.0014 mM against root growth of ryegrass showed 39-fold higher herbicidal activity than glyphosate. Besides, this compound was found to be nontoxic to human and animal cells, indicating the potential application as a water-soluble herbicide for ryegrass control.


Assuntos
Compostos de Amônio , Echinochloa , Herbicidas , Herbicidas/toxicidade , Sais , Terebintina , Água , Controle de Plantas Daninhas
7.
J Asian Nat Prod Res ; 23(6): 545-555, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32856467

RESUMO

Pyridine acylhydrazone derivatives of isopimaric acid were synthesized and characterized. The minimum inhibitory concentrations of the compounds against five bacteria were determined and most of the compounds displayed some degree of antibacterial activity. The results showed that antimicrobial activity against Streptococcus pneumoniae improved when halogen atoms were introduced into the isopimaric acid, especially when one bromine atom was introduced in the para-position of isopimaric acid. Compound isopimaric acid (5-bromo pyridine-2-formaldehyde) acylhydrazone exhibited a significant antitumorial activity against hepatocarcioma cells (HepG-2) and breast cancer cells (MDA-MB-231), with inhibition degrees of 74.21% and 70.39%, respectively, at 100 µM.[Formula: see text].


Assuntos
Fenantrenos , Antibacterianos/farmacologia , Ácidos Carboxílicos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Piridinas/farmacologia , Relação Estrutura-Atividade
8.
Sensors (Basel) ; 20(5)2020 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-32182668

RESUMO

Over the past few years, the Internet of Things (IoT) has been greatly developed with one instance being smart home devices gradually entering into people's lives. To maximize the impact of such deployments, home-based activity recognition is required to initially recognize behaviors within smart home environments and to use this information to provide better health and social care services. Activity recognition has the ability to recognize people's activities from the information about their interaction with the environment collected by sensors embedded within the home. In this paper, binary data collected by anonymous binary sensors such as pressure sensors, contact sensors, passive infrared sensors etc. are used to recognize activities. A radial basis function neural network (RBFNN) with localized stochastic-sensitive autoencoder (LiSSA) method is proposed for the purposes of home-based activity recognition. An autoencoder (AE) is introduced to extract useful features from the binary sensor data by converting binary inputs into continuous inputs to extract increased levels of hidden information. The generalization capability of the proposed method is enhanced by minimizing both the training error and the stochastic sensitivity measure in an attempt to improve the ability of the classifier to tolerate uncertainties in the sensor data. Four binary home-based activity recognition datasets including OrdonezA, OrdonezB, Ulster, and activities of daily living data from van Kasteren (vanKasterenADL) are used to evaluate the effectiveness of the proposed method. Compared with well-known benchmarking approaches including support vector machine (SVM), multilayer perceptron neural network (MLPNN), random forest and an RBFNN-based method, the proposed method yielded the best performance with 98.35%, 86.26%, 96.31%, 92.31% accuracy on four datasets, respectively.


Assuntos
Atividades Humanas/classificação , Monitorização Ambulatorial/métodos , Rede Nervosa , Adulto , Serviços de Assistência Domiciliar , Humanos , Internet das Coisas , Masculino , Processos Estocásticos , Máquina de Vetores de Suporte
10.
Angew Chem Int Ed Engl ; 57(9): 2388-2392, 2018 02 23.
Artigo em Inglês | MEDLINE | ID: mdl-29291260

RESUMO

Chemically inert, mechanically tough, cationic metallo-polyelectrolytes were conceptualized and designed as durable anion-exchange membranes (AEMs). Ring-opening metathesis polymerization (ROMP) of cobaltocenium-containing cyclooctene with triazole as the only linker group, followed by backbone hydrogenation, led to a new class of AEMs with a polyethylene-like framework and alkaline-stable cobaltocenium cation for ion transport. These AEMs exhibited excellent thermal, chemical and mechanical stability, as well as high ion conductivity.

11.
J Cell Mol Med ; 21(8): 1593-1604, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28244687

RESUMO

Within the vascular endothelial growth factor (VEGF) family of five subtypes, VEGF165 secreted by endothelial cells has been identified to be the most active and widely distributed factor that plays a vital role in courses of angiogenesis, vascularization and mesenchymal cell differentiation. Hair follicle stem cells (HFSCs) can be harvested from the bulge region of the outer root sheath of the hair follicle and are adult stem cells that have multi-directional differentiation potential. Although the research on differentiation of stem cells (such as fat stem cells and bone marrow mesenchymal stem cells) to the endothelial cells has been extensive, but the various mechanisms and functional forms are unclear. In particular, study on HFSCs' directional differentiation into vascular endothelial cells using VEGF165 has not been reported. In this study, VEGF165 was used as induction factor to induce the differentiation from HFSCs into vascular endothelial cells, and the results showed that Notch signalling pathway might affect the differentiation efficiency of vascular endothelial cells. In addition, the in vivo transplantation experiment provided that HFSCs could promote angiogenesis, and the main function is to accelerate host-derived neovascularization. Therefore, HFSCs could be considered as an ideal cell source for vascular tissue engineering and cell transplantation in the treatment of ischaemic diseases.


Assuntos
Células Endoteliais/efeitos dos fármacos , Folículo Piloso/efeitos dos fármacos , Isquemia/terapia , Neovascularização Fisiológica/efeitos dos fármacos , Células-Tronco/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/farmacologia , Animais , Antígenos CD/genética , Antígenos CD/metabolismo , Caderinas/genética , Caderinas/metabolismo , Diferenciação Celular , Colágeno/química , Combinação de Medicamentos , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Feminino , Regulação da Expressão Gênica , Folículo Piloso/citologia , Folículo Piloso/metabolismo , Membro Posterior/irrigação sanguínea , Membro Posterior/efeitos dos fármacos , Humanos , Isquemia/genética , Isquemia/metabolismo , Isquemia/patologia , Laminina/química , Masculino , Camundongos , Camundongos Nus , Molécula-1 de Adesão Celular Endotelial a Plaquetas/genética , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Cultura Primária de Células , Proteoglicanas/química , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Células-Tronco/citologia , Células-Tronco/metabolismo , Engenharia Tecidual/métodos
12.
Opt Express ; 23(2): 1800-5, 2015 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-25835934

RESUMO

We perform heterodyned optical Kerr gated (HOKG) ballistic imaging of an object hidden behind a turbid medium using a femtosecond laser. The experimental results show that an optimum heterodyning angle should be selected to acquire the highest spatial resolution of the HOKG imaging system. The optimum heterodyning angle depends on the scattering parameters of the turbid media, and it decreases with increasing optical density or decreasing thickness of the turbid medium.

13.
Opt Express ; 22(23): 28100-8, 2014 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-25402050

RESUMO

We proposed a novel biased optical Kerr gated imaging (BOKGI) method for ultrafast imaging. The imaging performance of the BOKGI system has been investigated. Experimental results showed that by using the BOKGI, the high spatial frequency components of the detected object could be effectively retrieved, which are often filtered by the photo-induced soft aperture in a conventional OKGI system. Comparing with the conventional OKGI method, the BOKGI method could enhance the sharpness of images and provide a higher spatial resolution of the imaging system. In addition, the influence of the biased angle on the BOKGI performance has been also investigated.


Assuntos
Diagnóstico por Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas
14.
Nanoscale Horiz ; 2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39036841

RESUMO

Dynamic DNA-based nanodevices offer versatile molecular-level operations, but the majority of them suffer from sluggish kinetics, impeding the advancement of device complexity. In this work, we present the self-assembly of a cationic peptide with DNA to expedite toehold-mediated DNA strand displacement (TMSD) reactions, a fundamental mechanism enabling the dynamic control and actuation of DNA nanostructures. The target DNA is modified with a fluorophore and a quencher, so that the TMSD process can be monitored by recording the time-dependent fluorescence changes. The boosting effect of the peptides is found to be dependent on the peptide/DNA N/P ratio, the toehold/invader binding affinity, and the ionic strength with stronger effects observed at lower ionic strengths, suggesting that electrostatic interactions play a key role. Furthermore, we demonstrate that the cationic peptide enhances the responsiveness and robustness of DNA machinery tweezers or logic circuits (AND and OR) involving multiple strand displacement reactions in parallel and cascade, highlighting its broad utility across DNA-based systems of varying complexity. This work offers a versatile approach to enhance the efficiency of toehold-mediated DNA nanodevices, facilitating flexible design and broader applications.

15.
Luminescence ; 28(3): 407-11, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22777916

RESUMO

A novel method for the detection of trace estradiol valerate (EV) in pharmaceutical preparations and human serum was developed by inhibition of luminol chemiluminescence (CL) by estradiol valerate on the zinc deuteroporphyrin (ZnDP)-enhanced luminol-K3 Fe(CN)6 chemiluminescence system. Under optimized experimental conditions, CL intensity and concentration of estradiol valerate had a good linear relationship in the ranges of 8.0 × 10(-8) to 1.0 × 10(-5) g/mL. Detection limit (3σ) was estimated to be 3.5 × 10(-8) g/mL. The proposed method was applied successfully for the determination of estradiol valerate in pharmaceutical preparations and human serum and recoveries were 97.0-105.0% and 95.5-106.0%, respectively. The possible mechanism of the CL system is discussed.


Assuntos
Estradiol/análogos & derivados , Análise de Injeção de Fluxo/métodos , Medições Luminescentes/métodos , Preparações Farmacêuticas/análise , Estradiol/análise , Estradiol/sangue , Humanos , Limite de Detecção , Luminescência , Luminol/química
16.
Chem Commun (Camb) ; 59(98): 14540-14543, 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-37987146

RESUMO

DNA is self-assembled with Fmoc-amino acids and Cu2+ to construct a supramolecular catechol oxidase-mimetic catalyst, which exhibits remarkable activity in catalyzing colorimetric reactions. This catalytic system is used for the detection of DNA hybridization with a high selectivity and a low detection limit.


Assuntos
Colorimetria , Oxirredutases , DNA/química , Catecol Oxidase , Aminoácidos , Limite de Detecção
17.
ACS Nano ; 17(24): 24753-24762, 2023 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-38061002

RESUMO

Toehold-mediated DNA strand displacement (TMSD) is a powerful tool for controlling DNA-based molecular reactions and devices. However, the slow kinetics of TMSD reactions often limit their efficiency and practical applications. Inspired by the chemical structures of natural DNA-operating enzymes (e.g., helicase), we designed lysine-rich peptides to self-assemble with DNA-based systems. Our approach allows for accelerating the TMSD reactions, even during multiple displacement events, enhancing their overall efficiency and utility. We found that the acceleration is dependent on the peptide's sequence, length, and concentration as well as the length of the DNA toehold domain. Molecular dynamics simulations revealed that the peptides promote toehold binding between the double-stranded target and the single-stranded invader, thereby facilitating strand displacement. Furthermore, we integrated our approach into a horseradish peroxidase-mimicking DNAzyme, enabling the dynamic modulation of enzymatic functions on and off. We anticipate that the established acceleration of strand displacement reactions and the modulation of enzymatic activities offer enhanced functionality and control in the design of programmable DNA-based nanodevices.


Assuntos
DNA Catalítico , DNA Catalítico/metabolismo , DNA/química , Cinética
18.
J Mater Chem B ; 11(30): 7117-7125, 2023 08 02.
Artigo em Inglês | MEDLINE | ID: mdl-37409588

RESUMO

The de novo design of artificial biocatalysts with enzyme-like active sites and catalytic functions has long been an attractive yet challenging goal. In this study, we present a nucleotide-Cu2+ complex, synthesized through a one-pot approach, capable of catalyzing ortho-hydroxylation reactions resembling those of minimalist monooxygenases. Both experimental and theoretical findings demonstrate that the catalyst, in which Cu2+ coordinates with both the nucleobase and phosphate moieties, forms a ternary-complex intermediate with H2O2 and tyramine substrates through multiple weak interactions. The subsequent electron transfer and hydrogen (or proton) transfer steps lead to the ortho-hydroxylation of tyramine, where the single copper center exhibits a similar function to natural dicopper sites. Moreover, Cu2+ bound to nucleotides or oligonucleotides exhibits thermophilic catalytic properties within the temperature range of 25 °C to 75 °C, while native enzymes are fully deactivated above 35 °C. This study may provide insights for the future design of oxidase-mimetic catalysts and serve as a guide for the design of primitive metallocentre-dependent enzymes.


Assuntos
Cobre , Oxigenases de Função Mista , Oxigenases de Função Mista/química , Oxigenases de Função Mista/metabolismo , Cobre/química , Oxirredução , Nucleotídeos/metabolismo , Peróxido de Hidrogênio , Tiramina
19.
Nat Commun ; 14(1): 4040, 2023 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-37419896

RESUMO

Enzymes fold into unique three-dimensional structures to distribute their reactive amino acid residues, but environmental changes can disrupt their essential folding and lead to irreversible activity loss. The de novo synthesis of enzyme-like active sites is challenging due to the difficulty of replicating the spatial arrangement of functional groups. Here, we present a supramolecular mimetic enzyme formed by self-assembling nucleotides with fluorenylmethyloxycarbonyl (Fmoc)-modified amino acids and copper. This catalyst exhibits catalytic functions akin those of copper cluster-dependent oxidases, and catalytic performance surpasses to date-reported artificial complexes. Our experimental and theoretical results reveal the crucial role of periodic arrangement of amino acid components, enabled by fluorenyl stacking, in forming oxidase-mimetic copper clusters. Nucleotides provide coordination atoms that enhance copper activity by facilitating the formation of a copper-peroxide intermediate. The catalyst shows thermophilic behavior, remaining active up to 95 °C in an aqueous environment. These findings may aid the design of advanced biomimetic catalysts and offer insights into primordial redox enzymes.


Assuntos
Cobre , Metaloproteínas , Cobre/química , Biomimética , Oxirredutases , Aminoácidos , Nucleotídeos
20.
IEEE Trans Cybern ; 52(2): 1269-1279, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32598288

RESUMO

Undersampling is a popular method to solve imbalanced classification problems. However, sometimes it may remove too many majority samples which may lead to loss of informative samples. In this article, the hashing-based undersampling ensemble (HUE) is proposed to deal with this problem by constructing diversified training subspaces for undersampling. Samples in the majority class are divided into many subspaces by a hashing method. Each subspace corresponds to a training subset which consists of most of the samples from this subspace and a few samples from surrounding subspaces. These training subsets are used to train an ensemble of classification and regression tree classifiers with all minority class samples. The proposed method is tested on 25 UCI datasets against state-of-the-art methods. Experimental results show that the HUE outperforms other methods and yields good results on highly imbalanced datasets.


Assuntos
Algoritmos , Projetos de Pesquisa
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