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1.
Cells ; 13(7)2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38607046

RESUMEN

Membrane nanotubes (NTs) are dynamic communication channels connecting spatially separated cells even over long distances and promoting the transport of different cellular cargos. NTs are also involved in the intercellular spread of different pathogens and the deterioration of some neurological disorders. Transport processes via NTs may be controlled by cytoskeletal elements. NTs are frequently observed membrane projections in numerous mammalian cell lines, including various immune cells, but their functional significance in the 'antibody factory' B cells is poorly elucidated. Here, we report that as active channels, NTs of B-lymphoma cells can mediate bidirectional mitochondrial transport, promoted by the cooperation of two different cytoskeletal motor proteins, kinesin along microtubules and myosin VI along actin, and bidirectional transport processes are also supported by the heterogeneous arrangement of the main cytoskeletal filament systems of the NTs. We revealed that despite NTs and axons being different cell extensions, the mitochondrial transport they mediate may exhibit significant similarities. Furthermore, we found that microtubules may improve the stability and lifespan of B-lymphoma-cell NTs, while F-actin strengthens NTs by providing a structural framework for them. Our results may contribute to a better understanding of the regulation of the major cells of humoral immune response to infections.


Asunto(s)
Estructuras de la Membrana Celular , Linfoma , Nanotubos , Animales , Citoesqueleto/metabolismo , Actinas/metabolismo , Nanotubos/química , Mitocondrias/metabolismo , Proteínas del Citoesqueleto/metabolismo , Linfoma/metabolismo , Mamíferos/metabolismo
2.
J Phys Chem Lett ; 15(16): 4400-4407, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38624102

RESUMEN

Gold nanorods (AuNRs) with unique optical properties play a pivotal role in applications in plasmonic imaging, small molecule detection, and photothermal therapy. However, challenges in DNA functionalization of AuNRs hinder their full potential due to the presence of a dense cetyltrimethylammonium bromide (CTAB) bilayer, impeding close DNA contact. In this study, we introduced a convenient approach for the rapid assembly of polyadenine (polyA) tailed DNA on AuNRs with control of DNA density, rigidity, and valence. We explored the impact of DNA with designed properties on the construction of core-satellite structures by employing AuNRs as cores and spherical gold nanoparticles (AuNSs) as satellites. Density, rigidity, and valence are identified as crucial factors for efficient construction. Specifically, polyA-tailed DNA modulated DNA density and reduced spatial hindrance and electrostatic repulsion, thereby facilitating the construction. Enhancing the rigidity of DNA and incorporating multiple binding sites can further improve the efficiency.


Asunto(s)
ADN , Oro , Nanotubos , Poli A , Oro/química , Nanotubos/química , ADN/química , Poli A/química , Nanopartículas del Metal/química , Cetrimonio/química
3.
Mikrochim Acta ; 191(5): 268, 2024 04 17.
Artículo en Inglés | MEDLINE | ID: mdl-38627271

RESUMEN

Hybrid nanozyme graphene quantum dots (GQDs) deposited TiO2 nanotubes (NTs) on titanium foil (Ti/TiO2 NTs-GQDs) were manufactured by bestowing the hybrid with the advantageous porous morphology, surface valence states, high surface area, and copious active sites. The peroxidase-like activity was investigated through the catalytic oxidation of chromogenic substrate 3,3',5,5'-tetramethylbenzidine (TMB) in the presence of H2O2, which can be visualized by the eyes. TiO2 NTs and GQDs comprising oxygen-containing functional groups can oxidize TMB in the presence of H2O2 by mimicking peroxidase enzymes. The peroxidase-mimicking activity of hybrid nanozyme was significantly escalated by introducing light illumination due to the photosensitive features of the hybrid material. The peroxidase-like activity of Ti/TiO2 NTs-GQDs enabled H2O2 determination over the linear range of 7 to 250 µM, with a LOD of 2.1 µM. The satisfying peroxidase activity is possibly due to the unimpeded access of H2O2 to the catalyst's active sites. The porous morphology provides the easy channeling of reactants and products. The periodic structure of the material also gave rise to acceptable reproducibility. Without material functionalization, the Ti/TiO2 NTs-GQDs can be a promising substitute for peroxidases for H2O2 detection.


Asunto(s)
Bencidinas , Grafito , Nanotubos , Puntos Cuánticos , Grafito/química , Peroxidasa/química , Puntos Cuánticos/química , Peróxido de Hidrógeno/química , Reproducibilidad de los Resultados , Nanotubos/química
4.
Anal Methods ; 16(16): 2597-2605, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38618693

RESUMEN

The highly infectious characteristics of coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), highlight the necessity of sensitive and rapid nucleocapsid (N) protein-based antigen testing for early triage and epidemic management. In this study, a colorimetric and photothermal dual-mode lateral flow immunoassay (LFIA) platform for the rapid and sensitive detection of the SARS-CoV-2 N protein was developed based on gold nanorods (GNRs), which possessed tunable local surface plasma resonance (LSPR) absorption peaks from UV-visible to near-infrared (NIR). The LSPR peak was adjusted to match the NIR emission laser 808 nm by controlling the length-to-diameter ratio, which could maximize the photothermal conversion efficiency and achieve photothermal detection signal amplification. Qualitative detection of SARS-CoV-2 N protein was achieved by observing the strip color, and the limit of detection was 2 ng mL-1, while that for photothermal detection was 0.096 ng mL-1. Artificial saliva samples spiked with the N protein were analyzed with the recoveries ranging from 84.38% to 107.72%. The intra-assay and inter-assay coefficients of variation were 6.76% and 10.39%, respectively. We further evaluated the reliability of this platform by detecting 40 clinical samples collected from nasal swabs, and the results matched well with that of nucleic acid detection (87.5%). This method shows great promise in early disease diagnosis and screening.


Asunto(s)
COVID-19 , Colorimetría , Proteínas de la Nucleocápside de Coronavirus , Oro , Nanotubos , SARS-CoV-2 , Oro/química , Nanotubos/química , SARS-CoV-2/inmunología , Colorimetría/métodos , Humanos , COVID-19/diagnóstico , Inmunoensayo/métodos , Proteínas de la Nucleocápside de Coronavirus/inmunología , Proteínas de la Nucleocápside de Coronavirus/química , Límite de Detección , Rayos Infrarrojos , Fosfoproteínas/análisis , Fosfoproteínas/química , Fosfoproteínas/inmunología
5.
Anal Chem ; 96(11): 4605-4611, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38457774

RESUMEN

Microscopic temperature imaging holds significant importance in various fields, particularly in the development of nanomaterials for photothermal therapy (PTT). In this study, we present an analytical method to probe cellular temperature based on chemical kinetics and additional luminescence quenching by photoswitchable naphthopyrans. Taking advantage of the rapid ring-closing reaction of naphthopyran, temperature sensing was realized with a linear relationship between the logarithmic decay time constant (ln τ) and the reciprocal temperature (T-1). To create luminescent temperature nanosensors, we harnessed the ability of ring-opened naphthopyran to quench the luminescence of a semiconducting polymer, resulting in a diverse array of probes. Structural modifications on the naphthopyran also provided a way to fine-tune the sensitivity and response window of the nanosensors. The method allowed cellular temperature imaging on a cost-effective fluorescence microscopic setup. As an application, the temperature increase induced by gold nanorods (AuNRs) in cell lysosomes was successfully monitored, laying the foundation for a new class of photoswitchable nanosensors with promising biological applications.


Asunto(s)
Nanoestructuras , Nanotubos , Temperatura , Nanotubos/química , Diagnóstico por Imagen
6.
Anal Chem ; 96(13): 5315-5322, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38511619

RESUMEN

Photoacoustic imaging (PAI) in the second near-infrared region (NIR-II), due to deeper tissue penetration and a lower background interference, has attracted widespread concern. However, the development of NIR-II nanoprobes with a large molar extinction coefficient and a high photothermal conversion efficiency (PCE) for PAI and photothermal therapy (PTT) is still a big challenge. In this work, the NIR-II CuTe nanorods (NRs) with large molar extinction coefficients ((1.31 ± 0.01) × 108 cm-1·M-1 at 808 nm, (7.00 ± 0.38) × 107 cm-1·M-1 at 1064 nm) and high PCEs (70% at 808 nm, 48% at 1064 nm) were synthesized by living Staphylococcus aureus (S. aureus) cells as biosynthesis factories. Due to the strong light-absorbing and high photothermal conversion ability, the in vitro PA signals of CuTe NRs were about 6 times that of indocyanine green (ICG) in both NIR-I and NIR-II. In addition, CuTe NRs could effectively inhibit tumor growth through PTT. This work provides a new strategy for developing NIR-II probes with large molar extinction coefficients and high PCEs for NIR-II PAI and PTT.


Asunto(s)
Nanopartículas , Nanotubos , Técnicas Fotoacústicas , Fototerapia/métodos , Técnicas Fotoacústicas/métodos , Staphylococcus aureus , Nanomedicina Teranóstica/métodos
7.
J Mol Graph Model ; 129: 108751, 2024 06.
Artículo en Inglés | MEDLINE | ID: mdl-38430695

RESUMEN

In this paper, the finite element method is utilized to evaluate the behavior of the armchair phosphorene nanotubes under the compressive loading. The energy equations of the molecular and structural mechanics are used to obtain the elemental properties. The critical compressive forces of various armchair phosphorene nanotubes are computed with clamped-clamped and clamped-free boundary conditions. Results show that the stability of armchair phosphorene nanotubes increases with increasing nanotube aspect ratio, particularly under clamped-clamped boundary conditions. Finally, the buckling mode shapes of armchair phosphorene nanotubes under different boundary conditions are compared. Our work offers valuable insights into how these nanotubes respond to mechanical stress, helps determine elemental properties, and investigates the effects of nanotube geometry and different boundary conditions on their stability. This knowledge has broad applications in fields like nanotechnology, materials science, and nanomechanics, advancing the understanding of nanoscale materials and their potential for various practical uses.


Asunto(s)
Nanotubos , Análisis de Elementos Finitos , Nanotubos/química , Nanotecnología/métodos , Elasticidad
8.
Mikrochim Acta ; 191(4): 213, 2024 03 21.
Artículo en Inglés | MEDLINE | ID: mdl-38512701

RESUMEN

Strontium-90 (90Sr) is a major radioactive component that has attracted great attention, but its detection remains challenging since there are no specific energy rays indicative of its presence. Herein, a biosensor that is capable of rapidly detecting Sr2+ ions is demonstrated. Simple colorimetric method for sensitive detection of Sr2+ with the help of single-stranded DNA was developed by preparing MnO2 nanorods as oxidase mimic catalysis 3,3',5,5'-tetramethylbenzidine (TMB). Under weakly acidic conditions, MnO2 exhibited a strong oxidase-mimicking activity to oxidize colorless TMB into blue oxidation products (oxTMB) with discernible absorbance signals. Nevertheless, the introduction of a guanine-rich DNA aptamer inhibited MnO2-mediated TMB oxidation and reduced oxTMB formation, resulting in blue fading and diminished absorbance. Upon the addition of strontium ions to the system, the aptamers formed a stable G-quadruplex structure with strontium ions, thereby restoring the oxidase-mimicking activity of MnO2. Under the best experimental conditions, the absorbance exhibits a linear relationship with the Sr2+ concentration within the range 0.01-200 µM, with a limit of detection of 0.0028 µM. When the concentration of Sr2+ from 10-8 to 10-6 mol L-1, a distinct color change gradient could be observed in paper-based sensor. We successfully applied this approach to determine Sr2+ in natural water samples, obtaining recoveries ranging from 97.6 to 103% with a relative standard deviation of less than 5%. By providing technical solutions for detection, our work contributed to the effective monitoring of transportation of radioactive Sr in the environment.


Asunto(s)
Técnicas Biosensibles , G-Cuádruplex , Nanotubos , Oxidorreductasas/química , Óxidos/química , Colorimetría/métodos , Compuestos de Manganeso/química , Estroncio , ADN , Técnicas Biosensibles/métodos
9.
Biomed Mater ; 19(3)2024 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-38537375

RESUMEN

The development of new three-dimensional biomaterials with advanced versatile properties is critical to the success of tissue engineering (TE) applications. Here, (a) bioactive decellularized tendon extracellular matrix (dECM) with a sol-gel transition feature at physiological temperature, (b) halloysite nanotubes (HNT) with known mechanical properties and bioactivity, and (c) magnetic nanoparticles (MNP) with superparamagnetic and osteogenic properties were combined to develop a new scaffold that could be used in prospective bone TE applications. Deposition of MNPs on HNTs resulted in magnetic nanostructures without agglomeration of MNPs. A completely cell-free, collagen- and glycosaminoglycan- rich dECM was obtained and characterized. dECM-based scaffolds incorporated with 1%, 2% and 4% MNP-HNT were analysed for their physical, chemical, andin vitrobiological properties. Fourier-transform infrared spectroscopy, x-ray powder diffractometry and vibrating sample magnetometry analyses confirmed the presence of dECM, HNT and MNP in all scaffold types. The capacity to form apatite layer upon incubation in simulated body fluid revealed that dECM-MNP-HNT is a bioactive material. Combining dECM with MNP-HNT improved the thermal stability and compressive strength of the macroporous scaffolds upto 2% MNP-HNT.In vitrocytotoxicity and hemolysis experiments showed that the scaffolds were essentially biocompatible. Human bone marrow mesenchymal stem cells adhered and proliferated well on the macroporous constructs containing 1% and 2% MNP-HNT; and remained metabolically active for at least 21 din vitro. Collectively, the findings support the idea that magnetic nanocomposite dECM scaffolds containing MNP-HNT could be a potential template for TE applications.


Asunto(s)
Nanotubos , Andamios del Tejido , Humanos , Arcilla/química , Andamios del Tejido/química , Estudios Prospectivos , Ingeniería de Tejidos/métodos , Fenómenos Magnéticos , Nanotubos/química , Matriz Extracelular/química
10.
J Mater Chem B ; 12(14): 3392-3403, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38512335

RESUMEN

In the face of the serious threat to human health and the economic burden caused by bacterial antibiotic resistance, 2D phosphorus nanomaterials have been widely used as antibacterial agents. Violet phosphorus nanosheets (VPNSs) are an exciting bandgap-adjustable 2D nanomaterial due to their good physicochemical properties, yet the study of VPNS-based antibiotics is still in its infancy. Here, a composite of gold nanorods (AuNRs) loaded onto VPNS platforms (VPNS/AuNR) is constructed to maximize the potential of VPNSs for antimicrobial applications. The loading with AuNRs not only enhances the photothermal performance via a localized surface plasmon resonance (LSPR) effect, but also enhances the light absorption capacity due to the narrowing of the band gap of the VPNSs, thus increasing the ROS generation capacity. The results demonstrate that VPNS/AuNR exhibits outstanding antibacterial properties and good biocompatibility. Attractively, VPNS/AuNR is then extensively tested for treating skin wound infections, suggesting promising in vivo antibacterial and wound-healing features. Our findings may open a novel direction to develop a versatile VPNS-based treatment platform, which can significantly boost the progress of VPNS exploration.


Asunto(s)
Nanotubos , Fosfenos , Humanos , Resonancia por Plasmón de Superficie , Nanotubos/química , Antibacterianos/farmacología , Fósforo
11.
Nat Commun ; 15(1): 2307, 2024 Mar 14.
Artículo en Inglés | MEDLINE | ID: mdl-38485920

RESUMEN

Contractile rings are formed from cytoskeletal filaments during cell division. Ring formation is induced by specific crosslinkers, while contraction is typically associated with motor protein activity. Here, we engineer DNA nanotubes and peptide-functionalized starPEG constructs as synthetic crosslinkers to mimic this process. The crosslinker induces bundling of ten to hundred DNA nanotubes into closed micron-scale rings in a one-pot self-assembly process yielding several thousand rings per microliter. Molecular dynamics simulations reproduce the detailed architectural properties of the DNA rings observed in electron microscopy. Theory and simulations predict DNA ring contraction - without motor proteins - providing mechanistic insights into the parameter space relevant for efficient nanotube sliding. In agreement between simulation and experiment, we obtain ring contraction to less than half of the initial ring diameter. DNA-based contractile rings hold promise for an artificial division machinery or contractile muscle-like materials.


Asunto(s)
Nanotubos , Proteínas , División Celular , Proteínas/metabolismo , Citoesqueleto de Actina/metabolismo , Miosinas/metabolismo , ADN/metabolismo
12.
Brain Res Bull ; 209: 110921, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447659

RESUMEN

Tunneling nanotubes (TNTs) have emerged as pivotal structures for intercellular communication, enabling the transfer of cellular components across distant cells. Their involvement in neurological disorders has attracted considerable scientific interest. This review delineates the functions of TNTs within the central nervous system, examining their role in the transmission of bioenergetic substrates, and signaling molecules, and their multifaceted impact on both physiological and pathological processes, with an emphasis on neurodegenerative diseases. The review highlights the selectivity and specificity of TNTs as dedicated pathways for intercellular cargo delivery, particularly under stress conditions that provoke increased TNT formation. The potential of TNTs as therapeutic targets is explored in depth. We pay particular attention to the interactions between astrocytes and neurons mediated by TNTs, which are fundamental to brain architecture and function. Dysfunctions in these interactions are implicated in the spread of protein aggregates and mitochondrial anomalies, contributing to the pathogenesis of neurodegenerative diseases. The review culminates with a synthesis of the current understanding of TNT biology and identifies research gaps, advocating for intensified exploration into TNTs as a promising therapeutic frontier.


Asunto(s)
Astrocitos , Estructuras de la Membrana Celular , Nanotubos , Enfermedades Neurodegenerativas , Humanos , Comunicación Celular/fisiología , Encéfalo , Neuronas , Comunicación
13.
Int J Pharm ; 655: 124007, 2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38493844

RESUMEN

Gold core mesoporous silica shell (AuMSS) nanorods are multifunctional nanomedicines that can act simultaneously as photothermal, drug delivery, and bioimaging agents. Nevertheless, it is reported that once administrated, nanoparticles can be coated with blood proteins, forming a protein corona, that directly impacts on nanomedicines' circulation time, biodistribution, and therapeutic performance. Therefore, it become crucial to develop novel alternatives to improve nanoparticles' half-life in the bloodstream. In this work, Polyethylenimine (PEI) and Red blood cells (RBC)-derived membranes were combined for the first time to functionalize AuMSS nanorods and simultaneously load acridine orange (AO). The obtained results revealed that the RBC-derived membranes promoted the neutralization of the AuMSS' surface charge and consequently improved the colloidal stability and biocompatibility of the nanocarriers. Indeed, the in vitro data revealed that PEI/RBC-derived membranes' functionalization also improved the nanoparticles' cellular internalization and was capable of mitigating the hemolytic effects of AuMSS and AuMSS/PEI nanorods. In turn, the combinatorial chemo-photothermal therapy mediated by AuMSS/PEI/RBC_AO nanorods was able to completely eliminate HeLa cells, contrasting with the less efficient standalone therapies. Such data reinforce the potential of AuMSS nanomaterials to act simultaneously as photothermal and chemotherapeutic agents.


Asunto(s)
Antineoplásicos , Nanotubos , Neoplasias , Humanos , Células HeLa , Terapia Fototérmica , Membrana Eritrocítica , Dióxido de Silicio , Oro , Distribución Tisular , Fototerapia , Doxorrubicina/farmacología , Neoplasias/tratamiento farmacológico
14.
Dalton Trans ; 53(12): 5624-5631, 2024 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-38440932

RESUMEN

Noble metal nanomaterials have been widely demonstrated to possess intrinsic enzyme-like properties and have been increasingly applied in the fields of analysis and biomedicine. However, current exploration of high-activity noble metal nanozymes is still far from adequate. The construction of hollow structures and adjustment of their elemental composition are effective ways to improve the specific activity (SA) of nanozymes. In this study, trimetallic PtPdAu hollow nanorods (HNRs) were developed using a galvanic replacement reaction and Kirkendall effect. The catalytic experiment showed that the PtPdAu HNRs possessed outstanding peroxidase-like performance and their SA value was up to 563.71 U mg-1, which is remarkable among various previously reported nanozymes and higher than that of monometallic or bimetallic counterparts with similar structure and size prepared in this study. Electron paramagnetic resonance (EPR)measurements showed that the PtPdAu HNRs could contribute to the formation of hydroxyl radicals (˙OH) in catalyzing hydrogen peroxide. When using PtPdAu HNRs as a nanozyme in the colorimetric detection of H2O2 and ascorbic acid (AA), the limits of detection were as low as 1.8 µM and 0.068 µM, respectively. This study demonstrates that PtPdAu HNRs are high-activity nanozymes and have the potential to be applied in the field of analysis.


Asunto(s)
Nanotubos , Peroxidasa , Peroxidasa/química , Colorimetría , Peróxido de Hidrógeno/química , Peroxidasas/química , Colorantes/química
15.
Methods Mol Biol ; 2793: 131-141, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38526728

RESUMEN

Phage-nanomaterial conjugates are functional bio-nanofibers with various applications. While phage display can select for phages with desired genetically encoded functions and properties, nanomaterials can endow the phages with additional features at nanoscale dimensions. Therefore, combining phages with nanotechnology can construct bioconjugates with unique characteristics. One strategy for filamentous phages is to adsorb nanoparticles onto the side wall, composed of pVIII subunits, through electrostatic interactions. However, a noncovalent approach may cause offloading if the environment changes, potentially causing side effects especially for in vivo applications. Therefore, building stable phage-bioconjugates is an important need. We previously reported the construction of chimeric M13 phage conjugated with gold nanorods, named "phanorods," without weakening the binding affinity to the bacterial host cells. Herein, we give a detailed protocol for preparing the chimeric M13 phage and covalently conjugating gold nanorods to the phage.


Asunto(s)
Inovirus , Nanotubos , Bacteriófago M13/metabolismo , Oro/química , Técnicas de Visualización de Superficie Celular/métodos
16.
Int J Biol Macromol ; 265(Pt 1): 130894, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38490388

RESUMEN

Bamboo fibers (BF), as an important sustainable natural material, are becoming a hot alternative to synthetic fibers for the reinforcement of polypropylene (PP)-based composites. However, the weak interfacial compatibility between BF and PP as matrix and their inherent flammability limit the practical application of BF/PP composites (BPC). Here, a fire-safe BPC was fabricated by constructing flame-retardant interfacial layers containing tannic acid (TA)-Fe3+ complex and halloysite nanotubes (HNTs) on the fiber matrix followed by a hot-pressing process. The results showed that the interfacial chelating of TA with Fe3+ improved the dispersion of HNTs on the fibers and the interfacial interactions within the fiber matrix, resulting in the as-fabricated composite with significantly improved mechanical properties and water resistance. In addition, the flame-retardant composite exhibited higher thermal stability and enhanced residual char content. Moreover, the composite possessed significant flame-retardant performances with a reduction of 23.75 % in the total heat release and 32.44 % in the total smoke production, respectively, owing to the flame retarding in gaseous phase and condensed phase of TA-Fe3+@HNTs layers. This work offers a green and eco-friendly strategy to address the inherent problems of BPC material in terms of fire safety and interfacial compatibility, thus broadening their applications in the automotive interior and construction industries.


Asunto(s)
Industria de la Construcción , Retardadores de Llama , Nanotubos , Polifenoles , Arcilla , Polipropilenos
17.
Int J Biol Macromol ; 265(Pt 1): 130914, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38492702

RESUMEN

An innovative and simple nanocomposite denoted as MHNTs@PEI was synthesized for gallic acid (GA) analytical sample pretreatment. Polyethyleneimine (PEI) functionalized was binded onto magnetic halloysite nanotubes (MHNTs) to inhence adsorption capacity. MHNTs@PEI was obtained only through two steps modification (amination and PEI modification). Characterizations showed that there are layers of synthetic PEI on the tubular structure of the material and magnetic spheres on its surface, both indicating successful synthesis of the nanocomposite. Furthermore, the adsorption isotherms and kinetic modeling showed that the Langmuir model and pseudo-first-order model fit the adsorption data, respectively. MHNTs@PEI achieved an adsorption capacity of 158 mg·g-1. Overall, the abundant adsorption sites significantly improved the adsorption performance of the MHNTs@PEI. Regeneration tests demonstrated that the MHNTs@PEI exhibits effective adsorption, even after undergoing five consecutive cycles. Optimization of key parameters (ratio, volume of elution, elution time and frequency) in the process of adsorption and desorption was also conducted. The limit of detection (LOD) and that of the quantification (LOQ) were 0.19 and 0.63 µg·mL-1, respectively, and the recoveries were 95.67-99.43 %. Finally, the excellent magnetism (43.5 emu·g-1) and the adsorption feature of MHNTs@PEI enabled its successful utilization in analytical sample pretreatment through the extraction of GA from green tea.


Asunto(s)
Nanotubos , Contaminantes Químicos del Agua , Arcilla , Polietileneimina/química , Ácido Gálico , , Nanotubos/química , Adsorción , Fenómenos Magnéticos , Cinética
18.
Medicine (Baltimore) ; 103(9): e37352, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38428884

RESUMEN

Tumour necrosis factor alpha-induced protein 2 (TNFAIP2) is a gene induced by tumor necrosis factor in endothelial cells. TNFAIP2 has important functions in physiological and pathological processes, including cell proliferation, adhesion, migration, angiogenesis, inflammation, tunneling nanotube (TNT) formation and tumorigenesis. Moreover, TNFAIP2 is the key factor in the formation of TNTs. TNTs are related to signal transduction between different cell types and are considered a novel means of cell-to-cell communication. Mesenchymal stem cells (MSCs) are pluripotent cells that exhibit self-renewal, multidirectional differentiation, paracrine function and immune-regulating ability. MSCs can transfer mitochondria through TNTs to improve the functions of target cells. This review revealed that TNFAIP2 promotes the formation of TNTs and that MSCs rely on TNTs for mitochondrial transfer to ameliorate cell dysfunction.


Asunto(s)
Estructuras de la Membrana Celular , Células Endoteliales , Nanotubos , Humanos , Células Endoteliales/metabolismo , Mitocondrias/metabolismo , Sistema Nervioso Central
19.
Int J Nanomedicine ; 19: 2469-2485, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38476279

RESUMEN

Background: Titanium (Ti) surface with nanotubes array via anodization has been used in dental implants to enhance bone regeneration but little research was carried out to evaluate whether the presence of highly ordered or disorderly distributed nanotubes array on titanium surface would have an effect on cell behaviors of gingival fibroblasts. Methods: The present study fabricated nanotubes arrays with varied topography under different constant voltage of electrochemical anodization in fluorine-containing electrolyte. Human gingival fibroblasts (HGFs) from extracted third molar were harvested and co-cultured with titanium disks with different nanotubes topography. Then cell behaviors of gingival fibroblasts including cell proliferation, adhesive morphology and cell migration were estimated to investigate the influence of titanium nanotubes on cell biology. Besides, gene and protein expression of adhesion molecule (integrin ß1/ß4/α6, fibronectin, intracellular adhesion molecule-1 and collagen type I) were detected to evaluate the influence of different surfaces on cell adhesion. Results: Highly ordered arrays of nanotubes with pore diameter of 60 nm and 100 nm were fabricated under 30 and 40 V of anodization (TNT-30 and TNT-40) while disorderedly distributed nanotube arrays formed on the titanium surface under 50 V of anodization (TNT-50). Our results demonstrated that compared with raw titanium surface and disorderly nanotubes, surface with orderly nanotubes array increased cell area and aspect ratio, as well as cell migration ability in the early phase of cell adhesion (p<0.05). Besides, compared with raw titanium surface, gene and protein expression of adhesion molecules were upregulated in nanotubes groups to different extents, no matter whether in an orderly or disorderly array. Conclusion: Within the limitations of our study, we conclude that compared with raw titanium surface, the presence of nanotubes array on titanium surface could enhance cells adhesion and cell migration in the early phase. And compared with disorderly distributed nanotubes, highly ordered nanotubes array might provide a much more favorable surface for gingival fibroblasts to achieve a tight adhesion on the materials.


Asunto(s)
Implantes Dentales , Nanotubos , Humanos , Adhesión Celular , Titanio/química , Propiedades de Superficie , Fibroblastos , Nanotubos/química , Proliferación Celular
20.
ACS Appl Mater Interfaces ; 16(10): 12217-12231, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38480984

RESUMEN

Psoriasis, a prevalent chronic inflammatory skin ailment affecting approximately 2-3% of the global population, is characterized by persistent symptoms. Dexamethasone, a primary corticosteroid for treating psoriasis, demonstrates notable efficacy; however, its limited skin permeation results in documented adverse effects. To address this, the presented study employed a novel strategy to conjugate gold nanorod and dexamethasone and evaluate their potential for mitigating psoriatic inflammation using an imiquimod-induced mouse model and human skin cells. Our findings revealed enhanced cutaneous penetration of gold nanorod and dexamethasone conjugates compared with that of dexamethasone, owing to superior skin penetration. Gold nanorod and dexamethasone conjugates demonstrated an optimal pharmacological impact at minimal dosages without toxicity during extended use. To further enhance the effectiveness of gold nanorod and dexamethasone conjugates, 808 nm near-infrared laser irradiation, which reacts to gold, was additionally applied to achieve thermal elevation to expedite drug skin penetration. Supplementary laser irradiation at 808 nm significantly ameliorated psoriatic symptoms following deep gold nanorod and dexamethasone conjugates penetration. This corresponded with restored peroxisome proliferator-activated receptor-γ levels and accelerated dexamethasone release from the gold nanorod and dexamethasone conjugates complex. These findings highlight the potential of gold nanorod and dexamethasone conjugates to enhance drug penetration through dermal layers, thereby aiding psoriasis treatment. Moreover, its compatibility with photothermal therapy offers prospects for novel therapeutic interventions across various inflammatory skin disorders.


Asunto(s)
Nanotubos , Psoriasis , Animales , Ratones , Humanos , Terapia Fototérmica , Oro/farmacología , Oro/uso terapéutico , Psoriasis/tratamiento farmacológico , Dexametasona/farmacología , Dexametasona/uso terapéutico , Inflamación/tratamiento farmacológico
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