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The biological function of proteins is determined not only by their static structures but also by the dynamic properties of their conformational ensembles. Numerous high-accuracy static structure prediction tools have been recently developed based on deep learning; however, there remains a lack of efficient and accurate methods for exploring protein dynamic conformations. Traditionally, studies concerning protein dynamics have relied on molecular dynamics (MD) simulations, which incur significant computational costs for all-atom precision and struggle to adequately sample conformational spaces with high energy barriers. To overcome these limitations, various enhanced sampling techniques have been developed to accelerate sampling in MD. Traditional enhanced sampling approaches like replica exchange molecular dynamics (REMD) and frontier expansion sampling (FEXS) often follow the MD simulation approach and still cost a lot of computational resources and time. Variational autoencoders (VAEs), as a classic deep generative model, are not restricted by potential energy landscapes and can explore conformational spaces more efficiently than traditional methods. However, VAEs often face challenges in generating reasonable conformations for complex proteins, especially intrinsically disordered proteins (IDPs), which limits their application as an enhanced sampling method. In this study, we presented a novel deep learning model (named Phanto-IDP) that utilizes a graph-based encoder to extract protein features and a transformer-based decoder combined with variational sampling to generate highly accurate protein backbones. Ten IDPs and four structured proteins were used to evaluate the sampling ability of Phanto-IDP. The results demonstrate that Phanto-IDP has high fidelity and diversity in the generated conformation ensembles, making it a suitable tool for enhancing the efficiency of MD simulation, generating broader protein conformational space and a continuous protein transition path.
Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/química , Conformação Proteica , Simulação de Dinâmica Molecular , Domínios ProteicosRESUMO
The development of health literacy in China is relatively slow, and there are fewer health literacy scales, which is difficult to measure. Therefore, this study aims to promote the development of health literacy in China through the translation and application of the European Health Literacy Survey Questionnaire (HLS-EU-Q47). The scale was translated into Chinese, back-translated, culturally adapted and finally subjected to psychometric evaluation. A multi-stage stratified sampling method was used to select 2504 residents to test the reliability and validity of a questionnaire on health literacy. Exploratory factor analysis (EFA) and confirmatory factor analysis (CFA) were used to evaluate the validity of the results, and the back consistency was calculated by Cronbach's alpha coefficient. The EFA revealed that health care, disease prevention and health promotion explained 78.68% of the total variance in health literacy. The scale and its subscales demonstrated strong internal consistency, with high Cronbach's alpha coefficients ranging from 0.947 to 0.983. CFA confirmed the three-factor model's goodness-of-fit for the Chinese population. The dimensions of healthcare, disease prevention and health promotion showed high convergent validity with an average variance extracted values ranging from 0.52 to 0.60 and composite reliability values ranging from 0.94 to 0.96. The reliable and valid Chinese version of the HLS-EU-Q47 (HLS19-Q47-CN) developed and evaluated in this study is an important tool for assessing health literacy levels in the Chinese population. Furthermore, as this tool has global applicability, it has the potential to assess health literacy levels across different countries, enabling practical international comparisons.
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Letramento em Saúde , Psicometria , Humanos , Feminino , China , Masculino , Inquéritos e Questionários , Reprodutibilidade dos Testes , Adulto , Pessoa de Meia-Idade , Traduções , Comparação Transcultural , Análise Fatorial , Idoso , Adulto JovemRESUMO
Transition metal ions are served as disinfectant thousand years ago. However, the in vivo antibacterial application of metal ions is strongly restricted due to its high affinity with proteins and lack of appropriate bacterial targeting method. Herein, for the first time, Zn2+ -gallic acid nanoflowers (ZGNFs) are synthesized by a facile one-pot method without additional stabilizing agents. ZGNFs are stable in aqueous solution while can be easily decomposed in acidic environments. Besides, ZGNFs can specifically adhere onto Gram-positive bacteria, which is mediated by the interaction of quinone from ZGNFs and amino groups from teichoic acid of Gram-positive bacteria. ZGNFs exhibit high bactericidal effect toward various Gram-positive bacteria in multiple environments, which can be ascribed to the in situ Zn2+ release on bacterial surface. Transcriptome studies reveal that ZGNFs can disorder basic metabolic processes of Methicillin-resistant Staphylococcus aureus (MRSA). Moreover, in a MRSA-induced keratitis model, ZGNFs exhibit long-term retention in the infected corneal site and prominent MRSA elimination efficacy due to the self-targeting ability. This research not only reports an innovative method to prepare metal-polyphenol nanoparticles, but also provides a novel nanoplatform for targeted delivery of Zn2+ in combating Gram-positive bacterial infections.
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Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias Gram-Positivas , Íons , Zinco/farmacologia , Testes de Sensibilidade MicrobianaRESUMO
The foreign body response (FBR) to implanted biomaterials and biomedical devices can severely impede their functionality and even lead to failure. The discovery of effective anti-FBR materials remains a formidable challenge. Inspire by the enrichment of glutamic acid (E) and lysine (K) residues on human protein surfaces, a class of zwitterionic polypeptide (ZIP) hydrogels with alternating E and K sequences to mitigate the FBR is prepared. When subcutaneously implanted, the ZIP hydrogels caused minimal inflammation after 2 weeks and no obvious collagen capsulation after 6 months in mice. Importantly, these hydrogels effectively resisted the FBR in non-human primate models for at least 2 months. In addition, the enzymatic degradability of the gel can be controlled by adjusting the crosslinking degree or the optical isomerism of amino acid monomers. The long-term FBR resistance and controlled degradability of ZIP hydrogels open up new possibilities for a broad range of biomedical applications.
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Reação a Corpo Estranho , Hidrogéis , Animais , Hidrogéis/química , Camundongos , Materiais Biocompatíveis/química , Lisina/química , Primatas , Roedores , Ácido Poliglutâmico/químicaRESUMO
Polymeric elastomers are widely utilized in implantable biomedical devices. Nevertheless, the implantation of these elastomers can provoke a robust foreign body response (FBR), leading to the rejection of foreign implants and consequently reducing their effectiveness in vivo. Building effective anti-FBR coatings on those implants remains challenging. Herein, we introduce a coating-free elastomer with superior immunocompatibility. A super-hydrophilic anti-fouling zwitterionic layer can be generated in situ on the surface of the elastomer through a simple chemical trigger. This elastomer can repel the adsorption of proteins, as well as the adhesion of cells, platelets, and diverse microbes. The elastomer elicited negligible inflammatory responses after subcutaneous implantation in rodents for 2 weeks. No apparent fibrotic capsule formation was observed surrounding the elastomer after 6 months in rodents. Continuous subcutaneous insulin infusion (CSII) catheters constructed from the elastomer demonstrated prolonged longevity and performance compared to commercial catheters, indicating its great potential for enhancing and extending the performance of various implantable biomedical devices by effectively attenuating local immune responses. STATEMENT OF SIGNIFICANCE: The foreign body response remains a significant challenge for implants. Complicated coating procedures are usually needed to construct anti-fibrotic coatings on implantable elastomers. Herein, a coating-free elastomer with superior immunocompatibility was achieved using a zwitterionic monomer derivative. A pure zwitterionic layer can be generated on the elastomer surface through a simple chemical trigger. This elastomer significantly reduces protein adsorption, cell and bacterial adhesion, and platelet activation, leading to minimal fibrotic capsule formation even after six months of subcutaneous implantation in rodents. CSII catheters constructed from the PQCBE-H elastomer demonstrated prolonged longevity and performance compared to commercial catheters, highlighting the significant potential of PQCBE-H elastomers for enhancing and extending the performance of various implantable biomedical devices.
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Bacterial keratitis can lead to intraocular infection and even blindness without prompt and potent treatments. Currently, clinical abuse of antibiotics encouraged the evolution of resistant bacteria. Conventional antibiotic eye drops based keratitis treatment has been heavily restricted due to the lack of bactericidal efficiency and easy induction of bacterial resistance. Hence, developing an effective treatment strategy for bacterial keratitis is of great significance. In this work, we investigated ε-poly-l-lysine (EPL)-modified polydopamine (PDA) nanoparticles (EPL@PDA NPs)-mediated antibacterial photothermal therapy (aPTT), to cope with methicillin-resistant Staphylococcus aureus (MRSA)-induced keratitis. The surface modification of cationic peptide EPL enables EPL@PDA NPs to specifically target negatively charged MRSA and induces local hyperthermia to kill the bacteria under low ambient temperature. Under near-infrared (NIR) irradiation, the sterilization efficiency of EPL@PDA NPs suspension for MRSA in vitro was up to 99.96%. The EPL@PDA-mediated aPTT presented potent antibacterial efficacy in treating MRSA-induced keratitis with little corneal epithelial cytotoxicity and good biocompatibility. In conclusion, the bacterial-targeting aPTT platform in this work provides a prospective method for the management of MRSA-induced refractory bacterial keratitis.
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Dry eye disease (DED) impacts ≈30% of the world's population and causes serious ocular discomfort and even visual impairment. Inflammation is one core cause of the DED vicious cycle, a multifactorial deterioration in DED process. However, there are also reactive oxygen species (ROS) regulating inflammation and other points in the cycle from the upstream, leading to treatment failure of current therapies merely targeting inflammation. Accordingly, the authors develop micelle-based eye drops (more specifically p38 mitogen-activated protein kinases (MAPK) inhibitor Losmapimod (Los)-loaded and ROS scavenger Tempo (Tem)-conjugated cationic polypeptide micelles, designated as MTem/Los) for safe and efficient DED management. Cationic MTem/Los improve ocular retention of conjugated water-soluble Tem and loaded water-insoluble Los via electrostatic interaction with negatively charged mucin on the cornea, enabling an increase in therapeutic efficiency and a decrease in dosing frequency. Mechanistically, MTem/Los effectively decrease ROS over-production, reduce the expression of proinflammatory cytokines and chemokines, restrain macrophage proinflammatory phenotypic transformation, and inhibit cell apoptosis. Therapeutically, the dual-functional MTem/Los suppress the inflammatory response, reverse corneal epithelial defect, save goblet cell dysfunction, and recover tear secretion, thus breaking the vicious cycle and alleviating the DED. Moreover, MTem/Los exhibit excellent biocompatibility and tolerability for potential application as a simple and rapid treatment of oxidative stress- and inflammation-induced disorders, including DED.
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Síndromes do Olho Seco , Micelas , Anti-Inflamatórios/uso terapêutico , Síndromes do Olho Seco/tratamento farmacológico , Síndromes do Olho Seco/etiologia , Síndromes do Olho Seco/metabolismo , Humanos , Inflamação , Espécies Reativas de Oxigênio/metabolismo , ÁguaRESUMO
CRISPR-Cas12a system has been shown promising for nucleic acid diagnostics due to its rapid, portable and accurate features. However, cleavage of the amplicons and primers by the cis- and trans-activity of Cas12a hinders the attempts to integrate the amplification and detection into a single reaction. Through phosphorothioate modification of primers, we realized onepot detection with high sensitivity using plasmids of SARS-CoV-2, HPV16 and HPV18. We also identified the activated Cas12a has a much higher affinity to C nucleotide-rich reporter than others. By applying such reporters, the reaction time required for a lateral-flow readout was significantly reduced. Furthermore, to improve the specificity of the strip-based assay, we created a novel reporter and, when combined with a customized gold-nanopaticle strip, the readout was greatly enhanced owing to the elimination of the nonspecific signal. This established system, termed Targeting DNA by Cas12a-based Eye Sight Testing in an Onepot Reaction (TESTOR), was validated using clinical cervical scrape samples for human papillomaviruses (HPVs) detection. Our system represents a general approach to integrating the nucleic acid amplification and detection into a single reaction in CRISPR-Cas systems, highlighting its potential as a rapid, portable and accurate detection platform of nucleic acids.
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Spinal conditions related to intervertebral disc (IVD) degeneration cost billions of dollars in the US annually. Despite the prevalence and soaring cost, there is no specific treatment that restores the physiological function of the diseased IVD. Thus, it is vital to develop new treatment strategies to repair the degenerating IVD. Persons with IVD degeneration without back pain or radicular leg pain often do not require any intervention. Only patients with severe back pain related to the IVD degeneration or biomechanical instability are likely candidates for cell therapy. The IVD progressively degenerates with age in humans, and strategies to repair the IVD depend on the stage of degeneration. Cell therapy and cell-based gene therapy aim to address moderate disc degeneration; advanced stage disease may require surgery. Studies involving autologous, allogeneic, and xenogeneic cells have all shown good survival of these cells in the IVD, confirming that the disc niche is an immunologically privileged site, permitting long-term survival of transplanted cells. All of the animal studies reviewed here reported some improvement in disc structure, and 2 studies showed attenuation of local inflammation. Among the 50 studies reviewed, 25 used some type of scaffold, and cell leakage is a consistently noted problem, though some studies showed reduced cell leakage. Hydrogel scaffolds may prevent cell leakage and provide biomechanical support until cells can become established matrix producers. However, these gels need to be optimized to prevent this leakage. Many animal models have been leveraged in this research space. Rabbit is the most frequently used model (28 of 50), followed by rat, pig, and dog. Sheep and goat IVDs resemble those of humans in size and in the absence of notochordal cells. Despite this advantage, there were only 2 sheep and 1 goat studies of 50 studies in this cohort. It is also unclear if a study in large animals is needed before clinical trials since some of the clinical trials proceeded without a study in large animals. No animal studies or clinical trials completely restored IVD structure. However, results suggest cause for optimism. In light of the fact that patients primarily seek medical care for back pain, attenuating local inflammation should be a priority in benchmarks for success. Clinicians generally agree that short-term back pain should be treated conservatively. When interventions are considered, the ideal therapy should also be minimally invasive and concurrent with other procedures such as discography or discectomy. Restoration of tissue structure and preservation of spinal motion are desirable.