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1.
Proc Natl Acad Sci U S A ; 119(28): e2119761119, 2022 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-35737823

RESUMO

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike glycoprotein is the prime target for vaccines, diagnostics, and therapeutic antibodies against the virus. While anchored in the viral envelope, for effective virulence, the spike needs to maintain structural flexibility to recognize the host cell surface receptors and bind to them, a property that can heavily depend upon the dynamics of the unresolved domains, most prominently the stalk. Construction of the complete, membrane-bound spike model and the description of its dynamics are critical steps in understanding the inner working of this key element of the viral infection by SARS-CoV-2. Combining homology modeling, protein-protein docking, and molecular dynamics (MD) simulations, we have developed a full spike structure in a native membrane. Multimicrosecond MD simulations of this model, the longest known single trajectory of the full spike, reveal conformational dynamics employed by the protein to explore the surface of the host cell. In agreement with cryogenic electron microscopy (cryo-EM), three flexible hinges in the stalk allow for global conformational heterogeneity of spike in the fully glycosylated system mediated by glycan-glycan and glycan-lipid interactions. The dynamical range of the spike is considerably reduced in its nonglycosylated form, confining the area explored by the spike on the host cell surface. Furthermore, palmitoylation of the membrane domain amplifies the local curvature that may prime the fusion. We show that the identified hinge regions are highly conserved in SARS coronaviruses, highlighting their functional importance in enhancing viral infection, and thereby, provide points for discovery of alternative therapeutics against the virus.


Assuntos
COVID-19 , Interações entre Hospedeiro e Microrganismos , Processamento de Proteína Pós-Traducional , Receptores de Superfície Celular , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , COVID-19/virologia , Glicosilação , Humanos , Polissacarídeos , Ligação Proteica , Receptores de Superfície Celular/metabolismo , Glicoproteína da Espícula de Coronavírus/genética , Glicoproteína da Espícula de Coronavírus/metabolismo
2.
Alzheimers Dement ; 20(5): 3406-3415, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38567735

RESUMO

INTRODUCTION: Aducanumab selectively targets aggregated forms of amyloid beta (Aß), a neuropathological hallmark of Alzheimer's disease (AD). METHODS: PRIME was a Phase 1b, double-blind, randomized clinical trial of aducanumab. During the 12-month placebo-controlled period, participants with prodromal AD or mild AD dementia were randomized to receive aducanumab or placebo. At week 56, participants could enroll in a long-term extension (LTE), in which all participants received aducanumab. The primary endpoint was safety and tolerability. RESULTS: Amyloid-related imaging abnormalities-edema (ARIA-E) were the most common adverse event. Dose titration was associated with a decrease in the incidence of ARIA-E. Over 48 months, aducanumab decreased brain amyloid levels in a dose- and time-dependent manner. Exploratory endpoints suggested a continued benefit in the reduction of clinical decline over 48 months. DISCUSSION: The safety profile of aducanumab remained unchanged in the LTE of PRIME. Amyloid plaque levels continued to decrease in participants treated with aducanumab. HIGHLIGHTS: PRIME was a Phase 1b, double-blind, randomized clinical trial of aducanumab. We report cumulative safety and 48-month efficacy results from PRIME. Amyloid-related imaging abnormalities-edema (ARIA-E) were the most common adverse event (AE); 61% of participants with ARIA-E were asymptomatic. Dose titration was associated with a decrease in the incidence of ARIA-E. Aducanumab decreased levels of amyloid beta (Aß) in a dose- and time-dependent manner.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Anticorpos Monoclonais Humanizados , Humanos , Método Duplo-Cego , Anticorpos Monoclonais Humanizados/uso terapêutico , Doença de Alzheimer/tratamento farmacológico , Masculino , Feminino , Idoso , Peptídeos beta-Amiloides/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Resultado do Tratamento , Placa Amiloide/tratamento farmacológico , Relação Dose-Resposta a Droga
4.
J Clin Nurs ; 32(15-16): 5219-5229, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36448208

RESUMO

AIMS AND OBJECTIVES: To explore the acceptances and associated influences of organ donation in mainland China. BACKGROUND: The shortage of organ donors has limited the development of organ transplantation in China. It is important to recognise the target population who has high intention to donate their organs may change the status. DESIGN: We conducted a cross-sectional, multi-stage sampling study collected demographic data and individuals' willingness to accept organ donation. METHODS: A stepwise linear regression analysis was adopted to evaluate the factors related to the attitudes toward organ donation. RESULTS: We collected 11,031 valid samples for the survey. The willingness to donate organs among Chinese residents averaged 56.93 points. To be specific, males (ß = -.03), religious believers (ß = -.01) and parents with a different number of children (all: ß = -.04) are less willing to donate their organs. Respondents who live in an urban area (ß = .03), have higher education level (High school or junior college ß = .04, Bachelor degree or above ß = .09), feel anxious (mild, moderate ß = .02), feel pressured (moderate, severe ß = .08), have higher scores of the Short-Form Health Literacy Instrument (HLS-SF12) (ß = .31), The Self-Management Scale (SHMS) (ß = .16), EuroQol Five Dimensions Questionnaire (EQ-5D) (ß = .04) and EuroQol Visual Analogue Scale (EQ-VAS) (ß = .24), are more positive to donate. CONCLUSIONS: This study firstly discusses the public acceptance of organ donation through a nationwide sample around China. In this study, we discovered that Chinese residents' acceptance level of organ donation and that gender, house, anxiety, pressure, social support and health literacy were the main influencing factors on residents' attitudes. RELEVANCE TO CLINICAL PRACTICE: To figure out the Chinese public acceptance and its influencing factors of organ donation can help nurse transplant coordinators to recognise the target population and the obstacles of organ donation. PATIENT OR PUBLIC CONTRIBUTION: At the phase of collecting data, participants were recruited to fill the questionnaires.


Assuntos
Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Masculino , Criança , Humanos , Estudos Transversais , Conhecimentos, Atitudes e Prática em Saúde , Inquéritos e Questionários , China
5.
Alzheimers Dement ; 19(8): 3379-3388, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36795603

RESUMO

INTRODUCTION: We assessed the use of cerebrospinal fluid (CSF) biomarkers as an alternative to positron emission tomography (PET) for brain amyloid beta (Aß) pathology confirmation in the EMERGE and ENGAGE clinical trials. METHODS: EMERGE and ENGAGE were randomized, placebo-controlled, Phase 3 trials of aducanumab in participants with early Alzheimer's disease. Concordance between CSF biomarkers (Aß42, Aß40, phosphorylated tau 181, and total tau) and amyloid PET status (visual read) at screening was examined. RESULTS: Robust concordance between CSF biomarkers and amyloid PET visual status was observed (for Aß42/Aß40, AUC: 0.90; 95% CI: 0.83-0.97; p < 0.0001), confirming CSF biomarkers as a reliable alternative to amyloid PET in these studies. Compared with single CSF biomarkers, CSF biomarker ratios showed better agreement with amyloid PET visual reads, demonstrating high diagnostic accuracy. DISCUSSION: These analyses add to the growing body of evidence supporting CSF biomarkers as reliable alternatives to amyloid PET imaging for brain Aß pathology confirmation. HIGHLIGHTS: CSF biomarkers and amyloid PET concordance were assessed in Ph3 aducanumab trials. Robust concordance between CSF biomarkers and amyloid PET was observed. CSF biomarker ratios increased diagnostic accuracy over single CSF biomarkers. CSF Aß42/Aß40 demonstrated high concordance with amyloid PET. Results support CSF biomarker testing as a reliable alternative to amyloid PET.


Assuntos
Doença de Alzheimer , Peptídeos beta-Amiloides , Humanos , Peptídeos beta-Amiloides/líquido cefalorraquidiano , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/líquido cefalorraquidiano , Proteínas tau/líquido cefalorraquidiano , Tomografia por Emissão de Pósitrons , Amiloide , Biomarcadores/líquido cefalorraquidiano , Fragmentos de Peptídeos/líquido cefalorraquidiano
6.
Nature ; 537(7618): 50-6, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27582220

RESUMO

Alzheimer's disease (AD) is characterized by deposition of amyloid-ß (Aß) plaques and neurofibrillary tangles in the brain, accompanied by synaptic dysfunction and neurodegeneration. Antibody-based immunotherapy against Aß to trigger its clearance or mitigate its neurotoxicity has so far been unsuccessful. Here we report the generation of aducanumab, a human monoclonal antibody that selectively targets aggregated Aß. In a transgenic mouse model of AD, aducanumab is shown to enter the brain, bind parenchymal Aß, and reduce soluble and insoluble Aß in a dose-dependent manner. In patients with prodromal or mild AD, one year of monthly intravenous infusions of aducanumab reduces brain Aß in a dose- and time-dependent manner. This is accompanied by a slowing of clinical decline measured by Clinical Dementia Rating-Sum of Boxes and Mini Mental State Examination scores. The main safety and tolerability findings are amyloid-related imaging abnormalities. These results justify further development of aducanumab for the treatment of AD. Should the slowing of clinical decline be confirmed in ongoing phase 3 clinical trials, it would provide compelling support for the amyloid hypothesis.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/psicologia , Peptídeos beta-Amiloides/antagonistas & inibidores , Peptídeos beta-Amiloides/metabolismo , Anticorpos Monoclonais Humanizados/uso terapêutico , Placa Amiloide/tratamento farmacológico , Placa Amiloide/metabolismo , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Amiloide/efeitos dos fármacos , Amiloide/metabolismo , Peptídeos beta-Amiloides/química , Animais , Anticorpos Monoclonais Humanizados/administração & dosagem , Anticorpos Monoclonais Humanizados/efeitos adversos , Anticorpos Monoclonais Humanizados/farmacocinética , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Ensaios Clínicos Fase III como Assunto , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Pessoa de Meia-Idade , Modelos Biológicos , Placa Amiloide/patologia , Agregação Patológica de Proteínas/tratamento farmacológico , Solubilidade
7.
Bioorg Med Chem Lett ; 27(5): 1225-1232, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-28161087

RESUMO

A water-soluble exopolysaccharide, designated as LEP-2a, was isolated from Lachnum YM262 and purified by DEAE-Cellulose 52 and Sepharose CL-6B chromatographic columns. LEP-2a was a homogeneous polysaccharide, with a molecular weight of 1.52×105 Da. It was composed of mannose and galactose in a molar ratio of 20.6:1.0. Its structural features were investigated and elucidated by methylation analysis, periodate oxidation and Smith degradation, FT-IR and NMR spectroscopy. Based on obtained data, the backbone of LEP-2a consisted of 1,2-linked-α-d-mannose, 1,3-linked-α-d-mannose, 1,2,6-linked-α-d-mannose and 1,3-linked-ß-d-galactose and the side chains were attached to the backbone at O-6 position of 1,2,6-linked-α-d-mannose. In vitro antioxidant activity assay proved that LEP-2a possessed significant scavenging activities on superoxide, hydroxyl and DPPH radical. Furthermore, LEP-2a had strong in vitro moisture-absorption and -retention capacities as compared to chitosan and glycerol. These results suggested that LEP-2a might have a good potential to be applied as a multifunctional cosmetic additive in cosmetics.


Assuntos
Antioxidantes/química , Ascomicetos/química , Polissacarídeos/química , Água/química , Antioxidantes/isolamento & purificação , Antioxidantes/farmacologia , Ácido Ascórbico/química , Cromatografia Líquida de Alta Pressão , Espectroscopia de Ressonância Magnética , Estrutura Molecular , Oxirredução/efeitos dos fármacos , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Conservantes Farmacêuticos/química , Conservantes Farmacêuticos/isolamento & purificação , Conservantes Farmacêuticos/farmacologia , Solubilidade
8.
Alzheimer Dis Assoc Disord ; 30(1): 1-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26885819

RESUMO

Amyloid positron emission tomography (PET) imaging is being investigated as a screening tool to identify amyloid-positive patients as an enrichment strategy for Alzheimer disease (AD) clinical trial enrollment. In a multicenter, phase 1b trial, patients meeting clinical criteria for prodromal or mild AD underwent florbetapir PET scanning at screening. PET, magnetic resonance imaging, and coregistered PET/magnetic resonance imaging scans were reviewed by 2 independent readers and binary visual readings tabulated. Semiquantitative values of cortical to whole cerebellar standard uptake value ratios were computed (threshold 1.10). Of 278 patients with an evaluable PET scan, 170 (61%) and 185 (67%) were amyloid-positive by visual reading and quantitative analysis, respectively; 39% were excluded from the study due to an amyloid-negative scan based on visual readings. More ApoE ε4 carriers than noncarriers were amyloid-positive (80% vs. 43%). Comparison of visual readings with quantitative results identified 21 discordant cases (92% agreement). Interreader and intrareader agreements from visual readings were 98% and 100%, respectively. Amyloid PET imaging is an effective and feasible screening tool for enrollment of amyloid-positive patients with early stages of AD into clinical trials.


Assuntos
Doença de Alzheimer/patologia , Disfunção Cognitiva/patologia , Placa Amiloide/diagnóstico por imagem , Tomografia por Emissão de Pósitrons/métodos , Idoso , Idoso de 80 Anos ou mais , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/tratamento farmacológico , Compostos de Anilina , Anticorpos Monoclonais Humanizados/uso terapêutico , Apolipoproteína E4/genética , Apolipoproteínas E/genética , Encéfalo/patologia , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/tratamento farmacológico , Método Duplo-Cego , Etilenoglicóis , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino
9.
Biometrics ; 71(4): 918-28, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26177419

RESUMO

Predicting disease risk and progression is one of the main goals in many clinical research studies. Cohort studies on the natural history and etiology of chronic diseases span years and data are collected at multiple visits. Although, kernel-based statistical learning methods are proven to be powerful for a wide range of disease prediction problems, these methods are only well studied for independent data, but not for longitudinal data. It is thus important to develop time-sensitive prediction rules that make use of the longitudinal nature of the data. In this paper, we develop a novel statistical learning method for longitudinal data by introducing subject-specific short-term and long-term latent effects through a designed kernel to account for within-subject correlation of longitudinal measurements. Since the presence of multiple sources of data is increasingly common, we embed our method in a multiple kernel learning framework and propose a regularized multiple kernel statistical learning with random effects to construct effective nonparametric prediction rules. Our method allows easy integration of various heterogeneous data sources and takes advantage of correlation among longitudinal measures to increase prediction power. We use different kernels for each data source taking advantage of the distinctive feature of each data modality, and then optimally combine data across modalities. We apply the developed methods to two large epidemiological studies, one on Huntington's disease and the other on Alzheimer's Disease (Alzheimer's Disease Neuroimaging Initiative, ADNI) where we explore a unique opportunity to combine imaging and genetic data to study prediction of mild cognitive impairment, and show a substantial gain in performance while accounting for the longitudinal aspect of the data.


Assuntos
Aprendizado de Máquina/estatística & dados numéricos , Algoritmos , Doença de Alzheimer/diagnóstico , Doença de Alzheimer/etiologia , Biometria/métodos , Simulação por Computador , Progressão da Doença , Humanos , Doença de Huntington/diagnóstico , Doença de Huntington/etiologia , Estudos Longitudinais , Modelos Estatísticos , Estatísticas não Paramétricas , Máquina de Vetores de Suporte/estatística & dados numéricos
10.
Stat Med ; 34(16): 2427-43, 2015 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-25847392

RESUMO

We propose a simple approach predicting the cumulative risk of disease accommodating predictors with time-varying effects and outcomes subject to censoring. We use a nonparametric function for the coefficient of the time-varying effect and handle censoring through self-consistency equations that redistribute the probability mass of censored outcomes to the right. The computational procedure is extremely convenient and can be implemented by standard software. We prove large sample properties of the proposed estimator and evaluate its finite sample performance through simulation studies. We apply the method to estimate the cumulative risk of developing Huntington's disease (HD) from subjects with huntingtin gene mutation using a large collaborative HD study data and illustrate an inverse relationship between the cumulative risk of HD and the length of cytosine-adenine-guanine repeats in the huntingtin gene.


Assuntos
Idade de Início , Risco , Adulto , Bioestatística , Simulação por Computador , Humanos , Proteína Huntingtina , Doença de Huntington/genética , Pessoa de Meia-Idade , Modelos Estatísticos , Método de Monte Carlo , Proteínas do Tecido Nervoso/genética , Estudos Observacionais como Assunto/estatística & dados numéricos , Estatísticas não Paramétricas , Expansão das Repetições de Trinucleotídeos
11.
Clin Cosmet Investig Dermatol ; 17: 1007-1026, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737944

RESUMO

Introduction: Skin disease is one of the most common diseases and can affect people of all ages and races. However, the diagnosis of skin diseases via observation is a highly challenging task for both doctors and patients, and would benefit from the use of an intelligent system. Building a large benchmark with professional dermatologists is resource-intensive, and we believe that few-shot learning (FSL) methods would be helpful in solving the problem of annotated data scarcity. In this paper, we propose CDD-Net (Context Feature Fusion and Dual Attention Dermatology Net), a plug-in module for FSL clinical skin disease classification. Methods: Current FSL methods used in skin disease classification are limited to nonuniversal approaches and few disease classes. Our CDD-Net has a flexible structure, including a context feature-fusion module and dual-attention module to extract discriminating texture feature and emphasize contributive regions and channels. The context feature-fusion module localizes discriminatory texture details of skin lesions by integrating features from different layers, while the dual-attention module highlights discriminative regions via channel-wise and pixel-wise depictions based on weight vectors and restrains the contributions of irrelevant areas. We also present Derm104, a new clinical skin disease data benchmark that has significant coverage of rare diseases and reliable annotation between primary species and subspecies for better validation of our approach. Results: Our experiments validated the versatility of CDD-Net for different FSL methods and achieved an improvement in accuracy of up to 9.14 percentage points compared with the vanilla network, which can be considered state of the art. The ablation study also showed that the dual-attention module and context feature-fusion module worked efficiently in CDD-Net.

12.
Nat Commun ; 15(1): 5465, 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937478

RESUMO

Heat shuttling phenomenon is characterized by the presence of a non-zero heat flow between two bodies without net thermal bias on average. It was initially predicted in the context of nonlinear heat conduction within atomic lattices coupled to two time-oscillating thermostats. Recent theoretical works revealed an analog of this effect for heat exchanges mediated by thermal photons between two solids having a temperature dependent emissivity. In this paper, we present the experimental proof of this effect using systems made with composite materials based on phase change materials. By periodically modulating the temperature of one of two solids we report that the system akin to heat pumping with a controllable heat flow direction. Additionally, we demonstrate the effectiveness of a simultaneous modulation of two temperatures to control both the strength and direction of heat shuttling by exploiting the phase delay between these temperatures. These results show that this effect is promising for an active thermal management of solid-state technology, to cool down solids, to insulate them from their background or to amplify heat exchanges.

13.
Nat Commun ; 15(1): 4685, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824129

RESUMO

Designing ultralight conductive aerogels with tailored electrical and mechanical properties is critical for various applications. Conventional approaches rely on iterative, time-consuming experiments across a vast parameter space. Herein, an integrated workflow is developed to combine collaborative robotics with machine learning to accelerate the design of conductive aerogels with programmable properties. An automated pipetting robot is operated to prepare 264 mixtures of Ti3C2Tx MXene, cellulose, gelatin, and glutaraldehyde at different ratios/loadings. After freeze-drying, the aerogels' structural integrity is evaluated to train a support vector machine classifier. Through 8 active learning cycles with data augmentation, 162 unique conductive aerogels are fabricated/characterized via robotics-automated platforms, enabling the construction of an artificial neural network prediction model. The prediction model conducts two-way design tasks: (1) predicting the aerogels' physicochemical properties from fabrication parameters and (2) automating the inverse design of aerogels for specific property requirements. The combined use of model interpretation and finite element simulations validates a pronounced correlation between aerogel density and compressive strength. The model-suggested aerogels with high conductivity, customized strength, and pressure insensitivity allow for compression-stable Joule heating for wearable thermal management.

14.
Nat Nanotechnol ; 19(6): 782-791, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499859

RESUMO

One possible solution against the accumulation of petrochemical plastics in natural environments is to develop biodegradable plastic substitutes using natural components. However, discovering all-natural alternatives that meet specific properties, such as optical transparency, fire retardancy and mechanical resilience, which have made petrochemical plastics successful, remains challenging. Current approaches still rely on iterative optimization experiments. Here we show an integrated workflow that combines robotics and machine learning to accelerate the discovery of all-natural plastic substitutes with programmable optical, thermal and mechanical properties. First, an automated pipetting robot is commanded to prepare 286 nanocomposite films with various properties to train a support-vector machine classifier. Next, through 14 active learning loops with data augmentation, 135 all-natural nanocomposites are fabricated stagewise, establishing an artificial neural network prediction model. We demonstrate that the prediction model can conduct a two-way design task: (1) predicting the physicochemical properties of an all-natural nanocomposite from its composition and (2) automating the inverse design of biodegradable plastic substitutes that fulfils various user-specific requirements. By harnessing the model's prediction capabilities, we prepare several all-natural substitutes, that could replace non-biodegradable counterparts as exhibiting analogous properties. Our methodology integrates robot-assisted experiments, machine intelligence and simulation tools to accelerate the discovery and design of eco-friendly plastic substitutes starting from building blocks taken from the generally-recognized-as-safe database.

15.
Artigo em Inglês | MEDLINE | ID: mdl-37561624

RESUMO

The susceptibility of deep neural networks (DNNs) to adversarial intrusions, exemplified by adversarial examples, is well-documented. Conventional attacks implement unstructured, pixel-wise perturbations to mislead classifiers, which often results in a noticeable departure from natural samples and lacks human-perceptible interpretability. In this work, we present an adversarial attack strategy that implements fine-granularity, semantic-meaning-oriented structural perturbations. Our proposed methodology manipulates the semantic attributes of images through the use of disentangled latent codes. We engineer adversarial perturbations by manipulating either a single latent code or a combination thereof. To this end, we propose two unsupervised semantic manipulation strategies: one based on vector-disentangled representation and the other on feature map-disentangled representation, taking into consideration the complexity of the latent codes and the smoothness of the reconstructed images. Our empirical evaluations, conducted extensively on real-world image data, showcase the potency of our attacks, particularly against black-box classifiers. Furthermore, we establish the existence of a universal semantic adversarial example that is agnostic to specific images.

16.
J Colloid Interface Sci ; 651: 376-383, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37544226

RESUMO

The oxygen evolution reaction (OER) has garnered considerable attention because of its promising prospects in electrochemical energy conversion applications, but a significant challenge is faced by the insufficient understanding of sluggish OER kinetics. In fact, the intrinsic "acceptance-donation" process of electrons between active sites and reactants is responsible for improving OER activity. Herein, we suggest a multielement hybridization strategy to rematch spin electron occupation and energy splitting in high-entropy perovskites with multiple orbital coordination. In this concept, electronic hopping between t2g and eg orbitals among particular catalytic sites can be obviously enforced due to introducing more favorable energy levels from neighboring metal sites, which can demonstrate multistage orbital hybridization reaction activity. As a result, our proposed multistage-hybridized high-entropy perovskites display an impressive activity of 199.8 mA cm-2 as an overpotential of âˆ¼0.46 V, which is âˆ¼5.3 times that of pristine perovskite. Different from traditional catalyst designs, this study focuses on multistage orbital hybridization and electron exchange interactions through a multisite coordination mechanism to construct a fast reaction pathway. Our findings provide a new strategy for accelerating OER catalytic kinetics.

17.
Eur J Med Chem ; 246: 115028, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36528996

RESUMO

Post-translational methylation of histone lysine or arginine residues by histone methyltransferases (HMTs) plays crucial roles in gene regulation and diverse physiological processes and is implicated in a plethora of human diseases, especially cancer. Therefore, histone methyltransferases have been increasingly recognized as potential therapeutic targets. Consequently, the discovery and development of histone methyltransferase inhibitors have been pursued with steadily increasing interest over the past decade. However, the disadvantages of limited clinical efficacy, moderate selectivity, and propensity for acquired resistance have hindered the development of HMTs inhibitors. Targeted covalent modification represents a proven strategy for kinase drug development and has gained increasing attention in HMTs drug discovery. In this review, we focus on the discovery, characterization, and biological applications of covalent inhibitors for HMTs with emphasis on advancements in the field. In addition, we identify the challenges and future directions in this fast-growing research area of drug discovery.


Assuntos
Histonas , Neoplasias , Humanos , Histona Metiltransferases , Histona-Lisina N-Metiltransferase/metabolismo , Cisteína/uso terapêutico , Neoplasias/tratamento farmacológico
18.
JAMA Netw Open ; 6(8): e2328352, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37566417

RESUMO

Importance: In addition to technical barriers, public attitudes about the use of gene therapy have an important association with the clinical implementation of gene therapy. Objective: To investigate the factors associated with public acceptance of gene therapy among individuals in China. Design, Setting, and Participants: This cross-sectional study used data from a survey conducted among 21 880 individuals in mainland China from June 20 to August 31, 2022. Main Outcomes and Measures: Stepwise linear regression was used to analyze factors associated with public acceptance of gene therapy in 5 key areas: basic personal information (gender, region, age, and educational level), family situation (marital status, children, and cousins), economic status (assets, debts, and insurance coverage), health knowledge (health literacy score and media use), and physical health status (chronic illness, cancer, European Quality of Life 5-Dimension 5-Level version [EQ-5D-5L] score, and Brief Illness Perception Questionnaire [BIPQ] score). Acceptance scores were calculated based on a visual analog scale (range, 0-100, with higher scores indicating higher acceptance of gene therapy). Further subgroup analysis was carried out in different age subgroups and populations with or without chronic diseases. Results: A total of 21 880 participants (mean [SD] age, 39.4 [18.9] years; 10 947 female participants [50.0%]; 10 933 male participants [50.0%]) were analyzed in this study. The mean (SD) acceptance score of gene therapy in the survey was 60.56 (27.60). Compared with people aged 60 years or older, those aged 12 to 18 years had higher acceptance of gene therapy (ß = 1.48 [95% CI, 0.09-2.88]), while groups aged 19 to 30 years (ß = -3.43 [95% CI, -4.80 to -2.07]), 31 to 44 years (ß = -1.44 [95% CI, -2.76 to -0.12]), and 45 to 59 years (ß = -2.05 [95% CI, -3.27 to -0.83]) had lower acceptance. Compared with people living in Eastern China, those in Central China had lower acceptance of gene therapy (ß = -1.58 [95% CI, -2.54 to -0.62]), while those in Western China had higher acceptance (ß = 0.92 [95% CI, 0.09-1.76]). Higher educational level (undergraduate or above vs junior high or below) was associated with higher acceptance of gene therapy (ß = 1.56 [95% CI, 0.49-2.63]). Number of properties owned was also associated with higher acceptance of gene therapy (2 vs 0: ß = 2.38 [95% CI, 1.04-3.72]; ≥3 vs 0: ß = 4.66 [95% CI, 2.92-6.39]). Diagnosis of chronic disease was associated with lower acceptance of gene therapy (ß = -17.86 [95% CI, -20.49 to -15.24]), while diagnosis of cancer was associated with higher acceptance (ß = 6.99 [95% CI, 1.84-12.14]). Higher BIPQ score (ß = 0.40 [95% CI, 0.34-0.45]), higher health literacy score (ß = 0.70 [95% CI, 0.62-0.78]), and media use (ß = 0.49 [95% CI, 0.41-0.57]) were all associated with high acceptance of gene therapy, while a higher EQ-5D-5L score was associated with lower acceptance (ß = -0.29 [95% CI, -0.47 to -0.11]). For older people, being in debt, not having health insurance, and the EQ-5D-5L score were uniquely relevant factors. For people with chronic disease, having an undergraduate degree or higher, a diagnosis of cancer, and the BIPQ score were uniquely relevant factors. Conclusions and Relevance: These results suggest that basic personal information, economic status, health knowledge, and physical health status were the main factors associated with the acceptance of gene therapy. Improving the health literacy of the population and promoting trust in gene therapy may be effective ways to increase the acceptance of gene therapy. Poorer economic levels and worse disease states may reduce the public's willingness to accept gene therapy.


Assuntos
Neoplasias , Qualidade de Vida , Criança , Humanos , Masculino , Feminino , Idoso , Adulto , Estudos Transversais , China , Doença Crônica , Atitude
19.
ACS Appl Mater Interfaces ; 15(39): 46460-46469, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37733022

RESUMO

Severe injuries to the peripheral nervous system (PNS) require Schwann cells to aid in neuronal regeneration. Low-frequency electrical stimulation is known to induce the cogrowth of neurons and Schwann cells in an injured PNS. However, the correlations between electrical stimulation and Schwann cell viability are complex and not well understood. In this work, we develop a machine learning (ML)-integrated workflow that uses conductive hydrogel biointerfaces to evaluate the impacts of fabrication parameters and electrical stimulation on the Schwann cell viability. First, a hydrogel array with varying MXene and peptide loadings is fabricated, which serves as conductive biointerfaces to incubate Schwann cells and introduce various electrical stimulation (at different voltages and frequencies). Upon specific fabrication parameters and stimulation, the cell viability is evaluated and input into an artificial neural network model to train the model. Additionally, a data augmentation method is applied to synthesize 1000-fold virtual data points, enabling the construction of a high-accuracy prediction model (with a testing mean absolute error ≤11%). By harnessing the model's predictive power, we can accurately predict Schwann cell viability based on a given set of fabrication/stimulation parameters. Finally, the SHapley Additive exPlanations model interpretation provides several data-scientific insights that are validated by microscopic cellular observations. Our hybrid approach, involving conductive biointerface fabrication, ML algorithms, and data analysis, offers an unconventional platform to construct a preclinical prediction model at the cellular level.

20.
Front Public Health ; 10: 985218, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36211671

RESUMO

Background: China ranks 53rd out of 81 countries in the Quality of Death Index for 2021. Although hospice care demand is increasing, the progress remains slow. It is of great significance to explore the acceptances and associated influencing factors of hospice care. Methods: A cross-sectional survey by quota sampling was conducted in China from July 10th to September 15th, 2021. We collected demographic data and hospice care acceptance. A stepwise linear regression analysis was used. Results: This survey contained 11,031 valid questionnaire results to investigate the hospice care acceptance. It was found that individuals with undergraduate or above (ß = 0.04), more properties [2 (ß = 0.02), 3 (ß = 0.01)], and higher reimbursement types of medical insurance [employee health insurance and commercial health (ß = 0.03), government insurance (ß = 0.04)] had higher hospice acceptance willingness, while males (ß = -0.02) were less willing to accept than females. Psychological conditions [mild anxiety (ß = 0.03), moderate anxiety (ß = 0.01), moderate stress (ß = 0.05), and severe stress (ß = 0.06)] also played an important role. The Self-Management Scale (SHMS) (ß = 0.12), EuroQol Five Dimensions Questionnaire (EQ-5D) (ß = 0.05), EuroQol Visual Analog Scale (EQ-VAS) (ß = 0.21), Short-Form Family Health Scale (FHS-SF) (ß = 0.12), higher scores of the Short-Form Health Literacy Instrument (HLS-SF12) (ß = 0.16), and Perceived Social Support Scale (PSSS) (ß = 0.10) also contributed. Gender subgroup showed that in the male group, age, highest educational level, marital status, number of properties, whether having children, psychological conditions, the SHMS, EQ-5D, EQ-VAS, HLS-SF12, and PSSS showed significant difference. Urban and rural subgroups showed that age, highest educational level, number of properties, whether having chronic disease or psychological conditions, the SHMS, EQ-VAS, HLS-SF12, and PSSS were contributing factors in rural areas. Conclusion: The average score of acceptance of hospice care was 65.02 points. Gender, house, anxiety, pressure, social support, and health literacy were the main influencing factors on residents' attitudes.


Assuntos
Nível de Saúde , Cuidados Paliativos na Terminalidade da Vida , Criança , China , Estudos Transversais , Feminino , Humanos , Masculino , Qualidade de Vida
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