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1.
J Phys Chem B ; 128(27): 6492-6508, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38950000

RESUMO

Coarse-grained models designed for intrinsically disordered proteins and regions (IDP/Rs) usually omit some bonded potentials (e.g., angular and dihedral potentials) as a conventional strategy to enhance backbone flexibility. However, a notable drawback of this approach is the generation of inaccurate backbone conformations. Here, we addressed this problem by introducing residue-specific angular, refined dihedral, and correction map (CMAP) potentials, derived based on the statistics from a customized coil database. These bonded potentials were integrated into the existing Mpipi model, resulting in a new model, denoted as the "Mpipi+" model. Results show that the Mpipi+ model can improve backbone conformations. More importantly, it can markedly improve the secondary structure propensity (SSP) based on the experimental chemical shift and, consequently, succeed in capturing transient secondary structures. Moreover, the Mpipi+ model preserves the liquid-liquid phase separation (LLPS) propensities of IDPs.


Assuntos
Proteínas Intrinsicamente Desordenadas , Proteínas Intrinsicamente Desordenadas/química , Estrutura Secundária de Proteína , Modelos Moleculares , Conformação Proteica
2.
Int J Biol Macromol ; 272(Pt 1): 132861, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838884

RESUMO

Semen Coicis (S. Coicis) has been regarded as a valuable source of traditional herbal medicine in China for thousands of years. S. Coicis polysaccharides (SCPs) are one of the most important bioactive ingredients of S. Coicis, which have attracted worldwide attention, because of their great marketing potential and development prospects. Hot water extraction is currently the most commonly used method to isolate SCPs. The structural characteristics of SCPs have been extensively investigated through various advanced modern analytical techniques to dissect the structure-activity relationships. SCPs are mainly composed of diverse monosaccharides, from which Rha and Ara are the most prevalent glycosyl groups. In addition, the structures of SCPs are found to be closely related to their multiple biological activities, including antioxidant activity, immunomodulatory function, antitumor activity, hypoglycemic effect, intestinal microbiota regulatory activity, anti-inflammatory activity, among others. In view of this, this review aimed to provide systematic and current information on the isolation, structural characteristics, and bioactivities of SCPs to support their future applications as therapeutic agents and functional foods.


Assuntos
Polissacarídeos , Polissacarídeos/química , Polissacarídeos/farmacologia , Polissacarídeos/isolamento & purificação , Antioxidantes/farmacologia , Antioxidantes/química , Antioxidantes/isolamento & purificação , Humanos , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/isolamento & purificação , Animais , Relação Estrutura-Atividade , Monossacarídeos/análise , Monossacarídeos/química , Fatores Imunológicos/farmacologia , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação
3.
Materials (Basel) ; 17(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38730825

RESUMO

Medical titanium-based (Ti-based) implants in the human body are prone to infection by pathogenic bacteria, leading to implantation failure. Constructing antibacterial nanocoatings on Ti-based implants is one of the most effective strategies to solve bacterial contamination. However, single antibacterial function was not sufficient to efficiently kill bacteria, and it is necessary to develop multifunctional antibacterial methods. This study modifies medical Ti foils with Cu-doped Co3O4 rich in oxygen vacancies, and improves their biocompatibility by polydopamine (PDA/Cu-Ov-Co3O4). Under near-infrared (NIR) irradiation, nanocoatings can generate •OH and 1O2 due to Cu+ Fenton-like activity and a photodynamic effect of Cu-Ov-Co3O4, and the total reactive oxygen species (ROS) content inside bacteria significantly increases, causing oxidative stress of bacteria. Further experiments prove that the photothermal process enhances the bacterial membrane permeability, allowing the invasion of ROS and metal ions, as well as the protein leakage. Moreover, PDA/Cu-Ov-Co3O4 can downregulate ATP levels and further reduce bacterial metabolic activity after irradiation. This coating exhibits sterilization ability against both Escherichia coli and Staphylococcus aureus with an antibacterial rate of ca. 100%, significantly higher than that of bare medical Ti foils (ca. 0%). Therefore, multifunctional synergistic antibacterial nanocoating will be a promising strategy for preventing bacterial contamination on medical Ti-based implants.

4.
J Colloid Interface Sci ; 664: 309-318, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38479267

RESUMO

Although lots of nanomaterials modified anodes have been reported to improve the bacterial attachment and extracellular electron transfer (EET) in microbial fuel cells (MFCs), the lack of a three dimensional (3D) conductive and capacitive network severely limited MFCs performance. In this work, 3D conductive networks derived from mucor mycelia were grown on carbon cloth (CC), and capacitive FeMn phosphides/oxides were further anchored on these 3D networks by electrochemical deposition (denoted as FeMn/CMM@CC) to simultaneously address the above challenges. As a result, the multivalent metal active sites were evenly distributed on 3D conductive network, which favored the enrichment of exoelectrogens, mass transport and EET. Consequently, the as-prepared FeMn/CMM@CC anode displayed accumulated charge of 131.4C/m2, higher than bare CC. Meanwhile, FeMn/CMM@CC anode substantially promoted flavin excretion and the amounts of nano conduits. The abundance of Geobacter was 63 % on bare CC, and greatly increased to 83 % on FeMn/CMM@CC. MFCs equipped by FeMn/CMM@CC anode presented the power density of 3.06 W/m2 and coulombic efficiency (29.9 %), evidently higher than bare CC (1.29 W/m2, 7.3 %), and the daily chemical oxygen demand (COD) removal amount also increased to 92.6 mg/L/d. This work developed a facile method to optimize the abiotic-biotic interface by introducing 3D conductive and capacitive network, which was proved to be a promising strategy to modify macro-porous electrodes.


Assuntos
Fontes de Energia Bioelétrica , Fontes de Energia Bioelétrica/microbiologia , Elétrons , Condutividade Elétrica , Carbono/química , Transporte de Elétrons , Eletrodos , Eletricidade
5.
Int J Biol Macromol ; 265(Pt 2): 130891, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38493821

RESUMO

Avena sativa L. (A. sativa L.), commonly known as oat, is a significant cereal grain crop with excellent edible and medicinal value. Oat polysaccharides (OPs), the major bioactive components of A. sativa L., have received considerable attention due to their beneficial bioactivities. However, the isolation and purification methods of OPs lack innovation, and the structure-activity relationship remains unexplored. This review emphatically summarized recent progress in the extraction and purification methods, structural characteristics, biological activities, structure-to-function associations and the potential application status of OPs. Different materials and isolation methods can result in the differences in the structure and bioactivity of OPs. OPs are mainly composed of various monosaccharide constituents, including glucose, arabinose and mannose, along with galactose, xylose and rhamnose in different molar ratios and types of glycosidic bonds. OPs exhibited a broad molecular weight distribution, ranging from 1.34 × 105 Da to 4.1 × 106 Da. Moreover, structure-activity relationships demonstrated that the monosaccharide composition, molecular weight, linkage types, and chemical modifications are closely related to their multiple bioactivities, including immunomodulatory activity, antioxidant effect, anti-inflammatory activity, antitumor effects etc. This work can provide comprehensive knowledge, update information and promising directions for future exploitation and application of OPs as therapeutic agents and multifunctional food additives.


Assuntos
Avena , Polissacarídeos , Polissacarídeos/química , Antioxidantes/farmacologia , Antioxidantes/química , Monossacarídeos/química , Aditivos Alimentares
6.
Adv Healthc Mater ; 13(9): e2303222, 2024 04.
Artigo em Inglês | MEDLINE | ID: mdl-38296257

RESUMO

Nanozyme mediated catalytic therapy is an attractive strategy for cancer therapy. However, the nanozymes are tended to assemble into 3D architectures, resulting in poor catalytic efficiency for therapy. This study designs the assembly of nanozymes and natural enzymes into the layered structures featuring hexagonal pores as nanozyme clusterphene and investigates their catalytic therapy with the assistance of electric field. The nanozyme-based clusterphene consists of polyoxometalate (POM) and natural glucose oxidase (GOx), named POMG-based clusterphene, which facilitate multi-enzyme activities including peroxidase (POD), catalase (CAT), and glutathione oxidase (GPx). The highly ordered layers with hexagonal pores of POMG units significantly improve the peroxidase-like (POD-like) activity of the nanozyme and thus the sustained production of reactive oxygen species (ROS). At the same time, GOx can increase endogenous H2O2 and produce gluconic acid while consuming glucose, the nutrient of tumor cell growth. The results indicate that the POD-like activity of POMG-based clusterphene increase approximately sevenfold under electrical stimulation compared with Nd-substituted keggin type POM cluster (NdPW11). The experiments both in vitro and in vivo show that the proposed POMG-based clusterphene mediated cascade catalytic therapy is capable of efficient tumor inhibiting and preventing tumor proliferation in tumor-bearing mice model, promising as an excellent candidate for catalytic therapy.


Assuntos
Peróxido de Hidrogênio , Neoplasias , Animais , Camundongos , Peroxidases , Peroxidase , Catálise , Ciclo Celular , Glucose Oxidase , Neoplasias/tratamento farmacológico , Microambiente Tumoral
7.
Adv Healthc Mater ; 13(1): e2302028, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37672732

RESUMO

Sonodynamic therapy (SDT) has emerged as a highly effective modality for the treatment of malignant tumors owing to its powerful penetration ability, noninvasiveness, site-confined irradiation, and excellent therapeutic efficacy. However, the traditional SDT, which relies on oxygen availability, often fails to generate a satisfactory level of reactive oxygen species because of the widespread issue of hypoxia in the tumor microenvironment of solid tumors. To address this challenge, various approaches are developed to alleviate hypoxia and improve the efficiency of SDT. These strategies aim to either increase oxygen supply or prevent hypoxia exacerbation, thereby enhancing the effectiveness of SDT. In view of this, the current review provides an overview of these strategies and their underlying principles, focusing on the circulation of oxygen from consumption to external supply. The detailed research examples conducted using these strategies in combination with SDT are also discussed. Additionally, this review highlights the future prospects and challenges of the hypoxia-alleviated SDT, along with the key considerations for future clinical applications. These considerations include the development of efficient oxygen delivery systems, the accurate methods for hypoxia detection, and the exploration of combination therapies to optimize SDT outcomes.


Assuntos
Neoplasias , Terapia por Ultrassom , Humanos , Microambiente Tumoral , Neoplasias/terapia , Neoplasias/patologia , Hipóxia/terapia , Hipóxia/patologia , Oxigênio , Espécies Reativas de Oxigênio , Linhagem Celular Tumoral
8.
Int J Biol Macromol ; 257(Pt 1): 128565, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38061516

RESUMO

Portulaca oleracea L., also known as purslane, affiliates to the Portulacaceae family. It is an herbaceous succulent annual plant distributed worldwide. P. oleracea L. is renowned for its nutritional value and medicinal value, which has been utilized for thousands of years as Traditional Chinese Medicine (TCM). The extract derived from P. oleracea L. has shown efficacy in treating various diseases, including intestinal dysfunction and inflammation. Polysaccharides from P. oleracea L. (POP) are the primary constituents of the crude extract which have been found to have various biological activities, including antioxidant, antitumor, immune-stimulating, and intestinal protective effects. While many publications have highlighted on the structural identification and bioactivity evaluation of POP, the underlying structure-activity relationship of POP still remains unclear. In view of this, this review aims to focus on the extraction, purification, structural features and bioactivities of POP. In addition, the potential structure-activity relationship and the developmental perspective for future research of POP were also explored and discussed. The current review would provide a valuable research foundation and the up-to-date information for the future development and application of POP in the field of the functional foods and medicine.


Assuntos
Portulaca , Portulaca/química , Polissacarídeos/farmacologia , Polissacarídeos/química , Extratos Vegetais , Valor Nutritivo
9.
Adv Mater ; 36(8): e2307337, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37724878

RESUMO

Nanozymes, next-generation enzyme-mimicking nanomaterials, have entered an era of rational design; among them, Co-based nanozymes have emerged as captivating players over times. Co-based nanozymes have been developed and have garnered significant attention over the past five years. Their extraordinary properties, including regulatable enzymatic activity, stability, and multifunctionality stemming from magnetic properties, photothermal conversion effects, cavitation effects, and relaxation efficiency, have made Co-based nanozymes a rising star. This review presents the first comprehensive profiling of the Co-based nanozymes in the chemistry, biology, and environmental sciences. The review begins by scrutinizing the various synthetic methods employed for Co-based nanozyme fabrication, such as template and sol-gel methods, highlighting their distinctive merits from a chemical standpoint. Furthermore, a detailed exploration of their wide-ranging applications in biosensing and biomedical therapeutics, as well as their contributions to environmental monitoring and remediation is provided. Notably, drawing inspiration from state-of-the-art techniques such as omics, a comprehensive analysis of Co-based nanozymes is undertaken, employing analogous statistical methodologies to provide valuable guidance. To conclude, a comprehensive outlook on the challenges and prospects for Co-based nanozymes is presented, spanning from microscopic physicochemical mechanisms to macroscopic clinical translational applications.


Assuntos
Ciência Ambiental , Nanoestruturas , Catálise , Nanoestruturas/química
10.
J Ethnopharmacol ; 323: 117688, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38159827

RESUMO

ETHNOPHARMACOLOGIC RELEVANCE: Crataegus pinnatifida, commonly known as hawthorn, is a plant species with a long history of medicinal use in traditional Chinese medicine. Hawthorn polysaccharides (HP) have gained worldwide attention due to their decent biological activities and potential health benefits. Their excellent antioxidant activity, antitumor activity, immunomodulatory activity, hypoglycemic effect and hypolipidemic effects, intestinal microbiota modulatory activity makes them valuable in the field of ethnopharmacological research. AIM OF THE STUDY: The purpose of the current review is to provide a systematic and comprehensive summary of the latest literatures and put forward the future perspectives on hawthorn polysaccharides in the context of its extraction, purification, structural characteristics and bioactivities. Furthermore, the underlying structure-bioactivity relationship of hawthorn polysaccharides was also explored and discussed. The current review would provide the important research underpinnings and the update the information for future development and application of hawthorn polysaccharides in the pharmaceutical and functional food industries. MATERIALS AND METHODS: We use Google Scholar, CNKI, PubMed, Springer, Elsevier, Wiley, Web of Science and other online databases to search and obtain the literature on extraction, isolation, structural analysis and the biological activity of hawthorn polysaccharides published before October 2023. The key words are "extraction", "isolation and purification", "bioactivities", and "Crataegus pinnatifida polysaccharides ". RESULTS: Crataegus pinnatifida has been widely used for the treatment of cardiovascular diseases, digestive disorders, inflammatory and oxidative stress in traditional Chinese medicine. Polysaccharides are the key active components of Crataegus pinnatifida which have gained widespread attention. The structure and bioactivity of polysaccharides from Crataegus pinnatifida varies in terms of raw materials, extraction methods and purification techniques. Crataegus pinnatifida polysaccharides possess diverse bioactivities, including antitumor, immunomodulatory, hypoglycemic activity, cardioprotective and antioxidant activities, among others. These biological properties can not only lay firm foundation for the treatment of diverse diseases, but also provide a theoretical basis for the in-depth study of the structure-activity relationship. In addition, the underlying structure-activity relationship is also explored and discussed, and further research and development of hawthorn polysaccharides are also prospected. CONCLUSION: As a natural compound, hawthorn polysaccharides has garnered significant attention and held immense research potential. Hawthorn polysaccharides can be obtained through different extraction methods, including hot water extraction method, ultrasonic extraction method and enzymatic extraction method etc. The structures of hawthorn polysaccharides have also been characterized and reported in numerous studies. Moreover, hawthorn polysaccharides exhibit a wide range of bioactivities, such as the antioxidant activity, the antitumor activity, the immunomodulatory activity, the hypoglycemic effect and the hypolipidemic effect, as well as the intestinal microbiota modulatory activity. These diverse bioactivities contribute to the growing interest in hawthorn polysaccharides and its potential applications. Hawthorn polysaccharides has promising application prospects in various industries, including functional food, pharmaceuticals and biomedical research. Therefore, it is imperative to fully explore and harness the potential of hawthorn polysaccharides in the food and medicine fields.


Assuntos
Crataegus , Crataegus/química , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/química , Polissacarídeos/farmacologia , Polissacarídeos/uso terapêutico , Extratos Vegetais/farmacologia , Hipoglicemiantes
11.
Angew Chem Int Ed Engl ; 63(6): e202315031, 2024 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-38117015

RESUMO

Enzyme-powered nanomotors have demonstrated promising potential in biomedical applications, especially for catalytic tumor therapy, owing to their ability of self-propulsion and bio-catalysis. However, the fragility of natural enzymes limits their environmental adaptability and also therapeutic efficacy in catalysis-enabled tumor therapy. Herein, polyoxometalate-nanozyme-based light-driven nanomotors were designed and synthesized for targeted synergistic photothermal-catalytic tumor therapy. In this construct, the peroxidase-like activity of the P2 W18 Fe4 polyoxometalates-based nanomotors can provide self-propulsion and facilitate their production of reactive oxygen species thus killing tumor cells, even in the weakly acidic tumor microenvironment. Conjugated polydopamine endows the nanomotors with the capability of light-driven self-propulsion behavior. After 10 min of NIR (808 nm) irradiation, along with the help of epidermal growth factor receptor antibody, the targeted accumulation and penetration of nanomotors in the tumor enabled highly efficient synergistic photothermal-catalytic therapy. This approach overcomes the disadvantages of the intrinsically fragile nature of enzyme-powered nanomotors in physiological environments and, more importantly, provides a motility-behavior promoted synergistic anti-tumor strategy.


Assuntos
Ânions , Neoplasias , Polieletrólitos , Humanos , Neoplasias/terapia , Anticorpos , Catálise , Terapia Fototérmica , Microambiente Tumoral , Linhagem Celular Tumoral
12.
Biophys J ; 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37915169

RESUMO

Due to the vast length scale inside the cell nucleus, multiscale models are required to understand chromatin folding, structure, and dynamics and how they regulate genomic activities such as DNA transcription, replication, and repair. We study the interactions and structure of condensed phases formed by the universal building block of chromatin, the nucleosome core particle (NCP), using bottom-up multiscale coarse-grained (CG) simulations with a model extracted from all-atom MD simulations. In the presence of the multivalent cations Mg(H2O)62+ or CoHex3+, we analyze the internal structures of the NCP aggregates and the contributions of histone tails and ions to the aggregation patterns. We then derive a "super" coarse-grained (SCG) NCP model to study the macroscopic scale phase separation of NCPs. The SCG simulations show the formation of NCP aggregates with Mg(H2O)62+ concentration-dependent densities and sizes. Variation of the CoHex3+ concentrations results in highly ordered lamellocolumnar and hexagonal columnar phases in agreement with experimental data. The results give detailed insights into nucleosome interactions and for understanding chromatin folding in the cell nucleus.

13.
Chem Asian J ; 18(22): e202300749, 2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-37755123

RESUMO

The potential of reactive oxygen species (ROS) cancer therapy in tumor treatment has been greatly enhanced by the introduction of catalytically superior polyoxometalate (POM)-based nanoplatforms, mainly composed of atomic clusters consisting of pre-transition metals and oxygen. These nanoplatforms have unique advantages, such as Fenton activity at neutral pH, induction of cellular ferroptosis instead of just apoptosis, and sensitivity to external field stimulation. However, there are also inevitable challenges such as neutralization of ROS by the antioxidant system of the tumor microenvironment (TME), hypoxia, and limited hydrogen peroxide concentrations. This review article aims to provide an overview of recent research advancements in POM-based nanoplatforms for ROS therapy from the perspective of chemical reactions and biological processes, addressing endogenous and exogenous factors that affect the antitumor efficacy. Endogenous factors include the mechanism of ROS generation by POM, the impact of pH and antioxidant systems on POM, and the various manners of tumor cell death. Exogenous stimuli mainly include light, heat, X-rays, and electricity. The article analyzes the specific mechanisms of action of each influencing factor in the first two sections, concluding with the limitations of the present study and some possible directions for future research.


Assuntos
Antioxidantes , Neoplasias , Humanos , Espécies Reativas de Oxigênio/metabolismo , Neoplasias/patologia , Oxigênio , Linhagem Celular Tumoral , Peróxido de Hidrogênio , Microambiente Tumoral
14.
J Colloid Interface Sci ; 648: 327-337, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37301157

RESUMO

Commonly used dense arrays of nanomaterials on carbon cloth (CC) are not suitable to accommodate microorganisms in microbial fuel cells (MFCs) due to their unmatched size. To simultaneously enrich exoelectrogens and accelerate the extracellular electron transfer (EET) process, SnS2 nanosheets were selected as sacrificial templates to prepare binder-free N,S-codoped carbon microflowers (N,S-CMF@CC) by polymer coating and pyrolysis. N,S-CMF@CC showed a cumulative total charge of 125.70C/m2, approximately 2.11 times higher than that of CC, indicating its better electricity storage capacity. Moreover, the interface transfer resistance and diffusion coefficient in bioanodes were 42.68 Ω and 9.27 × 10-10 cm2/s, respectively, superior to CC (141.3 Ω and 1.06 × 10-11 cm2/s). Remarkably, N,S-codoped carbon microflowers excreted more flavin than CC, as confirmed by continuous fluorescence monitoring. Biofilm and 16S rRNA gene sequence analysis revealed that exoelectrogens were enriched, and nanoconduits were generated on the N,S-CMF@CC anode. In particular, flavin excretion was also promoted on our hierarchical electrode, effectively driving the EET process. MFCs equipped with the N,S-CMF@CC anode could deliver a power density of 2.50 W/m2, coulombic efficiency of 22.77 %, and chemical oxygen demand (COD) removal amount of 90.72 mg/L/d, higher than that of bare CC. These findings not only demonstrate that our anode is capable of solving the cell enrichment issue, but it may also increase EET rates by bound flavin with outer membrane c-type cytochromes (OMCs) to simultaneously boost the power generation and wastewater treatment performance of MFCs.


Assuntos
Fontes de Energia Bioelétrica , Carbono/química , Eletricidade , RNA Ribossômico 16S , Eletrodos , Compostos Orgânicos
15.
Chem Rec ; 23(5): e202300034, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37010422

RESUMO

Rhodium (Rh) is a non-toxic transition metal used as various nanomaterials with unique structures and properties. Rh-based nanozymes can mimic the activities of natural enzymes, overcome the limitation of the application scope of natural enzymes, and interact with various biological microenvironments to play a variety of functions. Rh-based nanozymes can be synthesized in various ways, and different modification and regulation methods can also enable users to control catalytic performance by adjusting enzyme active sites. The construction of Rh-based nanozymes has attracted great interest in the biomedical field and impacted the industry and other areas. This paper reviews the typical synthesis and modification strategies, unique properties, applications, challenges, and prospects of Rh-based nanozymes. Next, the unique features of Rh-based nanozymes are emphasized, including adjustable enzyme-like activity, stability, and biocompatibility. In addition, we discuss Rh-based nanozymes biosensors and detection, biomedical therapy, and industrial and other applications. Finally, the future challenges and prospects of Rh-based nanozymes are proposed.


Assuntos
Nanoestruturas , Ródio , Nanoestruturas/química , Catálise
16.
Adv Healthc Mater ; 12(20): e2300153, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36933000

RESUMO

The tumor microenvironment (TME) is a complex and variable region characterized by hypoxia, low pH, high redox status, overexpression of enzymes, and high-adenosine triphosphate concentrations. In recent years, with the continuous in-depth study of nanomaterials, more and more TME-specific response nanomaterials are used for tumor treatment. However, the complexity of the TME causes different types of responses with various strategies and mechanisms of action. Aiming to systematically demonstrate the recent advances in research on TME-responsive nanomaterials, this work summarizes the characteristics of TME and outlines the strategies of different TME responses. Representative reaction types are illustrated and their merits and demerits are analyzed. Finally, forward-looking views on TME-response strategies for nanomaterials are presented. It is envisaged that such emerging strategies for the treatment of cancer are expected to exhibit dramatic trans-clinical capabilities, demonstrating the extensive potential for the diagnosis and therapy of cancer.


Assuntos
Nanoestruturas , Neoplasias , Humanos , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Nanoestruturas/uso terapêutico , Nanoestruturas/química , Hipóxia , Microambiente Tumoral/fisiologia , Oxirredução
17.
Adv Healthc Mater ; 11(21): e2201733, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36050895

RESUMO

Manganese (Mn) has attracted widespread attention due to its low-cost, nontoxicity, and valence-rich transition. Various Mn-based nanomaterials have sprung up and are employed in diverse fields, particularly Mn-based nanozymes, which combine the physicochemical properties of Mn-based nanomaterials with the catalytic activity of natural enzymes, and are attracting a surge of research, especially in the field of biomedical research. In this review, the typical preparation strategies, catalytic mechanisms, advances and perspectives of Mn-based nanozymes for biomedical applications are systematically summarized. The application of Mn-based nanozymes in tumor therapy and sensing detection, together with an overview of their mechanism of action is highlighted. Finally, the prospective directions of Mn-based nanozymes from five perspectives: innovation, activity enhancement, selectivity, biocompatibility, and application broadening are discussed.


Assuntos
Manganês , Nanoestruturas , Manganês/química , Estudos Prospectivos , Catálise , Nanoestruturas/química , Íons
18.
J Colloid Interface Sci ; 627: 299-307, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35863189

RESUMO

Photothermal therapy (PTT) has been widely employed in tumor treatment due to the non-invasive, highly selective, and low toxic side effects. However, the limited penetration of laser couples with the metastasis and recurrence of tumors, thus failing to eliminate them. Here, we report that ceria-loaded gold@platinum (CeO2/Au@Pt) nanospheres modified with polyethylene glycol (PEG). exhibit dual enzymatic activities for photothermal-catalytic synergistic therapy of tumors. CeO2/Au@Pt nanospheres are constructed through the loading of ultra-small CeO2 into core-shell Au@Pt nanospheres. In such a construct, Au@Pt enables targeted PTT, thanks to exceptional photothermal properties, while CeO2 nanozymes alleviate tumor hypoxia and kill tumor cells by producing highly toxic hydroxyl radicals (·OH) based on catalase- and peroxidase-like activities. Synergistic photothermal-catalytic therapy is achieved by delivering nanozymes to the tumor microenvironment (TME) coupled with PTT. This photothermal-catalytic approach that combines simultaneous exogenous and endogenous activation is a potential option for tumor co-therapy.


Assuntos
Nanopartículas Metálicas , Nanosferas , Neoplasias , Catalase , Linhagem Celular Tumoral , Ouro/farmacologia , Ouro/uso terapêutico , Humanos , Nanopartículas Metálicas/uso terapêutico , Neoplasias/tratamento farmacológico , Terapia Fototérmica , Platina/farmacologia , Polietilenoglicóis , Microambiente Tumoral
19.
J Chem Theory Comput ; 18(6): 3948-3960, 2022 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-35580041

RESUMO

The nucleosome core particle (NCP) is a large complex of 145-147 base pairs of DNA and eight histone proteins and is the basic building block of chromatin that forms the chromosomes. Here, we develop a coarse-grained (CG) model of the NCP derived through a systematic bottom-up approach based on underlying all-atom MD simulations to compute the necessary CG interactions. The model produces excellent agreement with known structural features of the NCP and gives a realistic description of the nucleosome-nucleosome attraction in the presence of multivalent cations (Mg(H2O)62+ or Co(NH3)63+) for systems comprising 20 NCPs. The results of the simulations reveal structural details of the NCP-NCP interactions unavailable from experimental approaches, and this model opens the prospect for the rigorous modeling of chromatin fibers.


Assuntos
Histonas , Nucleossomos , Cromatina , DNA/química , Histonas/química , Íons/metabolismo
20.
Chem Rec ; 22(6): e202200019, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35352472

RESUMO

MXenes have aroused widespread interest in the biomedical field owing to their remarkable photo-thermal conversion capabilities combined with large specific surface areas. MXenes quantum dots (MQDs) have been synthesized either by the physical or chemical methods based on MXenes as precursors, which possess smaller size, higher photoluminescence, coupled with low cytotoxicity and many beneficial properties of MXenes, thereby having potential biomedical applications. Given this, this review summarized the synthesis methods, optical, surface and biological properties of MQDs along with their practical applications in the field of biomedicine. Finally, the authors make an outlook towards the synthesis, properties and applications of MQDs in the future biomedicine field.


Assuntos
Pontos Quânticos , Pontos Quânticos/química
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