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1.
Nat Commun ; 12(1): 2025, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33795690

RESUMEN

Circular dichroism (CD) has long been used to trace chiral molecular states and changes of protein configurations. In recent years, chiral plasmonic nanostructures have shown potential for applications ranging from pathogen sensing to novel optical materials. The plasmonic coupling of the individual elements of such metallic structures is a crucial prerequisite to obtain sizeable CD signals. We here identify and implement various coupling entities-chiral and achiral-to demonstrate chiral transfer over distances close to 100 nm. The coupling is realized by an achiral nanosphere situated between a pair of gold nanorods that are arranged far apart but in a chiral fashion using DNA origami. The transmitter particle causes a strong enhancement of the CD response, the emergence of an additional chiral feature at the resonance frequency of the nanosphere, and a redshift of the longitudinal plasmonic resonance frequency of the nanorods. Matching numerical simulations elucidate the intricate chiral optical fields in complex architectures.


Asunto(s)
Dicroismo Circular/métodos , ADN/química , Oro/química , Nanotubos/química , ADN/genética , ADN/ultraestructura , Nanopartículas del Metal/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Nanoestructuras/química , Nanoestructuras/ultraestructura , Estereoisomerismo
2.
Int J Mol Sci ; 22(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804239

RESUMEN

Cancer is one of the deadliest diseases in human history with extremely poor prognosis. Although many traditional therapeutic modalities-such as surgery, chemotherapy, and radiation therapy-have proved to be successful in inhibiting the growth of tumor cells, their side effects may vastly limited the actual benefits and patient acceptance. In this context, a nanomedicine approach for cancer therapy using functionalized nanomaterial has been gaining ground recently. Considering the ability to carry various anticancer drugs and to act as a photothermal agent, the use of carbon-based nanomaterials for cancer therapy has advanced rapidly. Within those nanomaterials, reduced graphene oxide (rGO), a graphene family 2D carbon nanomaterial, emerged as a good candidate for cancer photothermal therapy due to its excellent photothermal conversion in the near infrared range, large specific surface area for drug loading, as well as functional groups for functionalization with molecules such as photosensitizers, siRNA, ligands, etc. By unique design, multifunctional nanosystems could be designed based on rGO, which are endowed with promising temperature/pH-dependent drug/gene delivery abilities for multimodal cancer therapy. This could be further augmented by additional advantages offered by functionalized rGO, such as high biocompatibility, targeted delivery, and enhanced photothermal effects. Herewith, we first provide an overview of the most effective reducing agents for rGO synthesis via chemical reduction. This was followed by in-depth review of application of functionalized rGO in different cancer treatment modalities such as chemotherapy, photothermal therapy and/or photodynamic therapy, gene therapy, chemotherapy/phototherapy, and photothermal/immunotherapy.


Asunto(s)
Grafito/uso terapéutico , Nanomedicina/tendencias , Nanoestructuras/uso terapéutico , Neoplasias/terapia , Antineoplásicos/química , Antineoplásicos/uso terapéutico , Doxorrubicina/química , Doxorrubicina/uso terapéutico , Portadores de Fármacos/química , Portadores de Fármacos/uso terapéutico , Grafito/química , Humanos , Nanoestructuras/química , Neoplasias/patología , Fotoquimioterapia/métodos , Fototerapia/métodos
3.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807632

RESUMEN

The thoracic and peritoneal cavities are lined by serous membranes and are home of the serosal immune system. This immune system fuses innate and adaptive immunity, to maintain local homeostasis and repair local tissue damage, and to cooperate closely with the mucosal immune system. Innate lymphoid cells (ILCs) are found abundantly in the thoracic and peritoneal cavities, and they are crucial in first defense against pathogenic viruses and bacteria. Nanomaterials (NMs) can enter the cavities intentionally for medical purposes, or unintentionally following environmental exposure; subsequent serosal inflammation and cancer (mesothelioma) has gained significant interest. However, reports on adverse effects of NM on ILCs and other components of the serosal immune system are scarce or even lacking. As ILCs are crucial in the first defense against pathogenic viruses and bacteria, it is possible that serosal exposure to NM may lead to a reduced resistance against pathogens. Additionally, affected serosal lymphoid tissues and cells may disturb adipose tissue homeostasis. This review aims to provide insight into key effects of NM on the serosal immune system.


Asunto(s)
Sistema Inmunológico/inmunología , Nanoestructuras/química , Cavidad Peritoneal/fisiología , Membrana Serosa/inmunología , Cavidad Torácica/inmunología , Animales , Homeostasis/inmunología , Humanos , Inflamación/inmunología , Linfocitos/inmunología
4.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802425

RESUMEN

Supramolecular peptide hydrogels are gaining increased attention, owing to their potential in a variety of biomedical applications. Their physical properties are similar to those of the extracellular matrix (ECM), which is key to their applications in the cell culture of specialized cells, tissue engineering, skin regeneration, and wound healing. The structure of these hydrogels usually consists of a di- or tripeptide capped on the N-terminus with a hydrophobic aromatic group, such as Fmoc or naphthalene. Although these peptide conjugates can offer advantages over other types of gelators such as cross-linked polymers, they usually possess the limitation of being particularly sensitive to proteolysis by endogenous proteases. One of the strategies reported that can overcome this barrier is to use a peptidomimetic strategy, in which natural amino acids are switched for non-proteinogenic analogues, such as D-amino acids, ß-amino acids, or dehydroamino acids. Such peptides usually possess much greater resistance to enzymatic hydrolysis. Peptides containing dehydroamino acids, i.e., dehydropeptides, are particularly interesting, as the presence of the double bond also introduces a conformational restraint to the peptide backbone, resulting in (often predictable) changes to the secondary structure of the peptide. This review focuses on peptide hydrogels and related nanostructures, where α,ß-didehydro-α-amino acids have been successfully incorporated into the structure of peptide hydrogelators, and the resulting properties are discussed in terms of their potential biomedical applications. Where appropriate, their properties are compared with those of the corresponding peptide hydrogelator composed of canonical amino acids. In a wider context, we consider the presence of dehydroamino acids in natural compounds and medicinally important compounds as well as their limitations, and we consider some of the synthetic strategies for obtaining dehydropeptides. Finally, we consider the future direction for this research area.


Asunto(s)
Materiales Biocompatibles/química , Hidrogeles/química , Nanoestructuras/química , Péptidos/química , Peptidomiméticos/química , Aminoácidos/química , Animales , Humanos , Estructura Secundaria de Proteína
5.
Int J Mol Sci ; 22(5)2021 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-33802614

RESUMEN

In this study, dense gold-assembled SiO2 nanostructure (SiO2@Au) was successfully developed using the Au seed-mediated growth. First, SiO2 (150 nm) was prepared, modified by amino groups, and incubated by gold nanoparticles (ca. 3 nm Au metal nanoparticles (NPs)) to immobilize Au NPs to SiO2 surface. Then, Au NPs were grown on the prepared SiO2@Au seed by reducing chloroauric acid (HAuCl4) by ascorbic acid (AA) in the presence of polyvinylpyrrolidone (PVP). The presence of bigger (ca. 20 nm) Au NPs on the SiO2 surface was confirmed by transmittance electronic microscopy (TEM) images, color changes to dark blue, and UV-vis spectra broadening in the range of 450 to 750 nm. The SiO2@Au nanostructure showed several advantages compared to the hydrofluoric acid (HF)-treated SiO2@Au, such as easy separation, surface modification stability by 11-mercaptopundecanoic acid (R-COOH), 11-mercapto-1-undecanol (R-OH), and 1-undecanethiol (R-CH3), and a better peroxidase-like catalysis activity for 5,5'-Tetramethylbenzidine (TMB) and hydrogen peroxide (H2O2) reaction. The catalytic activity of SiO2@Au was two times better than that of HF-treated SiO2@Au. When SiO2@Au nanostructure was used as a surface enhanced Raman scattering (SERS) substrate, the signal of 4-aminophenol (4-ATP) on the surface of SiO2@Au was also stronger than that of HF-treated SiO2@Au. This study provides a potential method for nanoparticle preparation which can be replaced for Au NPs in further research and development.


Asunto(s)
Oro/química , Nanopartículas del Metal/química , Nanoestructuras/química , Dióxido de Silicio/química , Aminofenoles/química , Bencidinas/química , Técnicas Biosensibles/métodos , Catálisis , Ácido Fluorhídrico/química , Peróxido de Hidrógeno/química , Límite de Detección , Povidona/química , Plata/química , Compuestos de Sulfhidrilo/química
6.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-33806461

RESUMEN

The present study aimed to synthesize novel polycationic polymers composed of N-substituted L-2,3-diaminopropionic acid residues (DAPEGs) and investigate their cell permeability, cytotoxicity, and DNA-binding ability. The most efficient cell membrane-penetrating compounds (O2Oc-Dap(GO2)n-O2Oc-NH2, where n = 4, 6, and 8) showed dsDNA binding with a binding constant in the micromolar range (0.3, 3.4, and 0.19 µM, respectively) and were not cytotoxic to HB2 and MDA-MB-231 cells. Selected compounds used in the transfection of a GFP plasmid showed high transfection efficacy and minimal cytotoxicity. Their interaction with plasmid DNA and the increasing length of the main chain of tested compounds strongly influenced the organization and shape of the flower-like nanostructures formed, which were unique for 5/6-FAM-O2Oc-[Dap(GO2)]8-O2Oc-NH2 and typical for large proteins.


Asunto(s)
Permeabilidad de la Membrana Celular/fisiología , Ácidos Nucleicos/metabolismo , Polímeros/farmacología , beta-Alanina/análogos & derivados , Línea Celular , Línea Celular Tumoral , Humanos , Nanoestructuras/química , Plásmidos/metabolismo , Transfección/métodos , beta-Alanina/farmacología
7.
Langmuir ; 37(14): 4056-4063, 2021 04 13.
Artículo en Inglés | MEDLINE | ID: mdl-33793250

RESUMEN

A large subset of haptic surfaces employs electroadhesion to modulate both adhesion and friction at a sliding finger interface. The current theory of electroadhesion assumes that the applied electric field pulls the skin into stronger contact, increasing friction by increasing the real contact area, yet it is unknown what role environmental moisture plays in the effect. This paper uses atomic force microscopy (AFM)to determine the effect of humidity on the adhesion and friction between the single nanoscale asperity and individual human finger corneocytes. An analytical model of the total effective load of the AFM tip is developed to explain the humidity-voltage dependence of nanoscale adhesion and friction at contacting asperities. The results show that the electrowetting effect at the interface at high humidity accounts for 35% of the adhesive force but less than 8% of the total friction, implying that the electrowetting effect can be enhanced by optimizing surface topography to promote the formation and rupture of liquid menisci.


Asunto(s)
Electrohumectación , Fricción , Nanoestructuras/química , Piel/citología , Humanos , Humedad , Microscopía de Fuerza Atómica
8.
Int J Mol Sci ; 22(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799554

RESUMEN

In the skin care field, bacterial nanocellulose (BNC), a versatile polysaccharide produced by non-pathogenic acetic acid bacteria, has received increased attention as a promising candidate to replace synthetic polymers (e.g., nylon, polyethylene, polyacrylamides) commonly used in cosmetics. The applicability of BNC in cosmetics has been mainly investigated as a carrier of active ingredients or as a structuring agent of cosmetic formulations. However, with the sustainability issues that are underway in the highly innovative cosmetic industry and with the growth prospects for the market of bio-based products, a much more prominent role is envisioned for BNC in this field. Thus, this review provides a comprehensive overview of the most recent (last 5 years) and relevant developments and challenges in the research of BNC applied to cosmetic, aiming at inspiring future research to go beyond in the applicability of this exceptional biotechnological material in such a promising area.


Asunto(s)
Bacterias/química , Celulosa/farmacología , Cosméticos/química , Tecnología Química Verde , Polisacáridos Bacterianos/farmacología , Celulosa/química , Celulosa/aislamiento & purificación , Cosméticos/farmacología , Humanos , Nanoestructuras/química , Nanoestructuras/ultraestructura , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/aislamiento & purificación , Piel/efectos de los fármacos , Cuidados de la Piel/métodos
9.
Int J Nanomedicine ; 16: 2405-2417, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33814907

RESUMEN

Purpose: Ciprofloxacin (CIP) has poor lung targeting after oral inhalation. This study developed optimized inhalable nanostructured lipid carriers (NLCs) for CIP to enhance deposition and accumulation in deeper parts of the lungs for treatment of noncystic fibrosis bronchiectasis (NCFB). Methods: NLC formulations based on stearic acid and oleic acid were successfully prepared by hot homogenization and in vitro-characterized. CIP-NLCs were formulated into nanocomposite micro particles (NCMPs) for administration in dry powder inhalation (DPI) formulations by spray-drying (SD) using different ratios of chitosan (CH) as a carrier. DPI formulations were evaluated for drug content and in vitro deposition, and their mass median aerodynamic diameter (MMAD), fine particle fraction (FPF), fine particle dose (FPD), and emitted dose (ED) were determined. Results: The CIP-NLCs were in the nanometric size range (102.3 ± 4.6 nm), had a low polydispersity index (0.267 ± 0.12), and efficient CIP encapsulation (98.75% ± 0.048%), in addition to a spherical and smooth shape with superior antibacterial activity. The in vitro drug release profile of CIP from CIP-NLCs showed 80% release in 10 h. SD of CIP-NLCs with different ratios of CH generated NCMPs with good yield (>65%). The NCMPs had a corrugated surface, but with increasing lipid:CH ratios, more spherical, smooth, and homogenous NCMPs were obtained. In addition, there was a significant change in the FPF with increasing lipid:CH ratios (P ˂ 0.05). NCMP-1 (lipid:CH = 1:0.5) had the highest FPD (45.0 µg) and FPF (49.2%), while NCMP-3 (lipid:CH = 1:1.5) had the lowest FPF (37.4%). All NCMP powders had an MMAD in the optimum size range of 3.9-5.1 µm. Conclusion: Novel inhalable CIP NCMP powders are a potential new approach to improved target ability and delivery of CIP for NCFB treatment.


Asunto(s)
Bronquiectasia/tratamiento farmacológico , Ciprofloxacino/uso terapéutico , Portadores de Fármacos/química , Lípidos/química , Nanoestructuras/química , Administración por Inhalación , Antibacterianos/administración & dosificación , Antibacterianos/farmacología , Quitosano/química , Ciprofloxacino/administración & dosificación , Portadores de Fármacos/administración & dosificación , Liberación de Fármacos , Inhaladores de Polvo Seco , Fibrosis , Cinética , Liposomas , Pulmón , Pruebas de Sensibilidad Microbiana , Nanoestructuras/ultraestructura , Tamaño de la Partícula , Electricidad Estática
11.
Int J Nanomedicine ; 16: 2647-2665, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33854313

RESUMEN

Graphene is a new type of carbon nanomaterial discovered after fullerene and carbon nanotube. Due to the excellent biological properties such as biocompatibility, cell proliferation stimulating, and antibacterial properties, graphene and its derivatives have become emerging candidates for the development of novel cutaneous wound dressings and composite scaffolds. On the other hand, pre-clinical research on exosomes derived from mesenchymal stem cells (MSC-Exos) has been intensified for cell-free treatment in wound healing and cutaneous regeneration, via ameliorating the damaged microenvironment of the wound site. Here, we provide a comprehensive understanding of the latest studies and observations on the various effects of graphene-based nanomaterials (GBNs) and MSC-Exos during the cutaneous wound repair process, as well as the putative mechanisms thereof. In addition, we propose the possible forward directions of GBNs and MSC-Exos applications, expecting to promote the clinical transformation.


Asunto(s)
Exosomas/metabolismo , Grafito/química , Células Madre Mesenquimatosas/metabolismo , Nanoestructuras/química , Piel/patología , Cicatrización de Heridas , Animales , Humanos
12.
Int J Mol Sci ; 22(6)2021 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-33806998

RESUMEN

In recent times, food safety has become a topic of debate as the foodborne diseases triggered by chemical and biological contaminants affect human health and the food industry's profits. Though conventional analytical instrumentation-based food sensors are available, the consumers did not appreciate them because of the drawbacks of complexity, greater number of analysis steps, expensive enzymes, and lack of portability. Hence, designing easy-to-use tests for the rapid analysis of food contaminants has become essential in the food industry. Under this context, electrochemical biosensors have received attention among researchers as they bear the advantages of operational simplicity, portability, stability, easy miniaturization, and low cost. Two-dimensional (2D) nanomaterials have a larger surface area to volume compared to other dimensional nanomaterials. Hence, researchers nowadays are inclined to develop 2D nanomaterials-based electrochemical biosensors to significantly improve the sensor's sensitivity, selectivity, and reproducibility while measuring the food toxicants. In the present review, we compile the contribution of 2D nanomaterials in electrochemical biosensors to test the food toxicants and discuss the future directions in the field. Further, we describe the types of food toxicity, methodologies quantifying food analytes, how the electrochemical food sensor works, and the general biomedical properties of 2D nanomaterials.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Análisis de los Alimentos/métodos , Inocuidad de los Alimentos , Nanoestructuras , Contaminación de Alimentos/análisis , Sustancias Peligrosas/análisis , Humanos , Nanoestructuras/química , Reproducibilidad de los Resultados
13.
Int J Nanomedicine ; 16: 1631-1661, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33688183

RESUMEN

Molecular targeted therapy, a tumor therapy strategy that inhibits specific oncogenic targets, has been shown to modulate the immune response. In addition to directly inhibiting the proliferation and metastasis of tumor cells, molecular targeted drugs can activate the immune system through a variety of mechanisms, including by promoting tumor antigen processing and presentation, increasing intratumoral T cell infiltration, enhancing T cell activation and function, and attenuating the immunosuppressive effect of the tumor microenvironment. However, poor water solubility, insufficient accumulation at the tumor site, and nonspecific targeting of immune cells limit their application. To this end, a variety of nanomaterials have been developed to overcome these obstacles and amplify the immunomodulatory effects of molecular targeted drugs. In this review, we summarize the impact of molecular targeted drugs on the antitumor immune response according to their mechanisms, highlight the advantages of nanomaterials in enhancing the immunomodulatory effect of molecular targeted therapy, and discuss the current challenges and future prospects.


Asunto(s)
Inmunomodulación , Terapia Molecular Dirigida , Nanoestructuras/química , Animales , Humanos , Inmunosupresión , Inmunoterapia , Neoplasias/inmunología , Neoplasias/terapia
14.
Int J Nanomedicine ; 16: 1805-1817, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33692623

RESUMEN

Introduction: RNA interference is a promising therapy in glioma treatment. However, the application of RNA interference has been limited in glioma therapy by RNA instability and the lack of tumor targeting. Here, we report a novel DNA tetrahedron, which can effectively deliver small interfering RNA to glioma cells and induce apoptosis. Methods: siRNA, a small interfering RNA that can suppress the expression of survivin in glioma, was loaded into the DNA tetrahedron (TDN). To enhance the ability of active targeting of this nanoparticle, we modified one side of the DNA nanostructure with aptamer as1411 (As-TDN-R), which can selectively recognize the nucleolin in the cytomembrane of tumor cells. The modified nanoparticles were characterized by agarose gel electrophoresis, dynamic light scattering, and transmission electron microscopy. The serum stability was evaluated by agarose gel electrophoresis. Nucleolin was detected by Western blot and immunofluorescence, and targeted cellular uptake was examined by flow cytometry. The TUNEL assay, flow cytometry, and Western Blot were used to detect apoptosis in U87 cells. The gene silencing of survivin was examined by qPCR, Western Blot, and immunofluorescence. Results: As-TDN-R alone showed better stability towards siRNA, indicating that TDN was a good siRNA protector. Compared with TDN alone, there was increased intercellular uptake of As-TDN-R by U87 cells, evidenced by overexpressed nucleolin in glioma cell lines. TUNEL assay, flow cytometry, and Western Blot revealed increased apoptosis in the As-TDN-R group. The downregulation of survivin protein and mRNA expression levels indicated that As-TDN-R effectively silenced the target gene. Conclusion: The novel nanoparticle can serve as a good carrier for targeting siRNA delivery in glioma. Further exploration of the DNA nanostructure can greatly promote the application of DNA-based drug systems in glioma.


Asunto(s)
ADN/química , Técnicas de Transferencia de Gen , Glioma/terapia , Nanoestructuras/química , ARN Interferente Pequeño/administración & dosificación , Apoptosis/efectos de los fármacos , Aptámeros de Nucleótidos/química , Muerte Celular , Línea Celular Tumoral , Supervivencia Celular , Regulación hacia Abajo , Endocitosis , Silenciador del Gen , Glioma/patología , Células Endoteliales de la Vena Umbilical Humana , Humanos , Nanoestructuras/ultraestructura , Oligodesoxirribonucleótidos/química , Fosfoproteínas/metabolismo , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/metabolismo , Survivin/metabolismo
15.
ACS Appl Mater Interfaces ; 13(13): 14816-14843, 2021 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-33779135

RESUMEN

The pandemic outbreak of SARS-CoV-2, with millions of infected patients worldwide, has severely challenged all aspects of public health. In this regard, early and rapid detection of infected cases and providing effective therapeutics against the virus are in urgent demand. Along with conventional clinical protocols, nanomaterial-based diagnostics and therapeutics hold a great potential against coronavirus disease 2019 (COVID-19). Indeed, nanoparticles with their outstanding characteristics would render additional advantages to the current approaches for rapid and accurate diagnosis and also developing prophylactic vaccines or antiviral therapeutics. In this review, besides presenting an overview of the coronaviruses and SARS-CoV-2, we discuss the introduced nanomaterial-based detection assays and devices and also antiviral formulations and vaccines for coronaviruses.


Asunto(s)
/administración & dosificación , /terapia , Nanoestructuras/administración & dosificación , /efectos de los fármacos , /tratamiento farmacológico , Humanos , Nanoestructuras/química , /aislamiento & purificación
16.
Molecules ; 26(4)2021 Feb 11.
Artículo en Inglés | MEDLINE | ID: mdl-33670175

RESUMEN

A range of solution-processed organic and hybrid organic-inorganic solar cells, such as dye-sensitized and bulk heterojunction organic solar cells have been intensely developed recently. TiO2 is widely employed as electron transporting material in nanostructured TiO2 perovskite-sensitized solar cells and semiconductor in dye-sensitized solar cells. Understanding the optical and electronic mechanisms that govern charge separation, transport and recombination in these devices will enhance their current conversion efficiencies under illumination to sunlight. In this work, density functional theory with Perdew-Burke Ernzerhof (PBE) functional approach was used to explore the optical and electronic properties of three modeled TiO2 brookite clusters, (TiO2)n=5,8,68. The simulated optical absorption spectra for (TiO2)5 and (TiO2)8 clusters show excitation around 200-400 nm, with (TiO2)8 cluster showing higher absorbance than the corresponding (TiO2)5 cluster. The density of states and the projected density of states of the clusters were computed using Grid-base Projector Augmented Wave (GPAW) and PBE exchange correlation functional in a bid to further understand their electronic structure. The density of states spectra reveal surface valence and conduction bands separated by a band gap of 1.10, 2.31, and 1.37 eV for (TiO2)5, (TiO2)8, and (TiO2)68 clusters, respectively. Adsorption of croconate dyes onto the cluster shifted the absorption peaks to higher wavelengths.


Asunto(s)
Teoría Funcional de la Densidad , Nanoestructuras/química , Energía Solar , Titanio/química , Adsorción , Compuestos de Calcio/química , Suministros de Energía Eléctrica , Electrónica , Electrones , Óptica y Fotónica/tendencias , Óxidos/química , Luz Solar
17.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670583

RESUMEN

Blocking the PD-1/PD-L1 pathway can diminish immunosuppression and enhance anticancer immunity. PD-1/PD-L1 blockade can be realized by aptamers, which have good biocompatibility and can be synthesized in quantity economically. For in vivo applications, aptamers need to evade renal clearance and nuclease digestion. Here we investigated whether DNA nanostructures could be used to enhance the function of PD-L1 aptamers. Four PD-L1 aptamers (Apt) were built into a Holliday Junction (HJ) to form a tetravalent DNA nanostructure (Apt-HJ). The average size of Apt-HJ was 13.22 nm, which was above the threshold for renal clearance. Apt-HJ also underwent partial phosphorothioate modification and had improved nuclease resistance. Compared with the monovalent PD-L1 aptamer, the tetravalent Apt-HJ had stronger affinity to CT26 colon cancer cells. Moreover, Apt-HJ markedly boosted the antitumor efficacy in vivo vs. free PD-L1 aptamers without raising systemic toxicity. The results indicate that multiple aptamers attached to a DNA nanostructure may significantly improve the function of PD-L1 aptamers in vivo.


Asunto(s)
Antineoplásicos/farmacología , Aptámeros de Nucleótidos/química , Antígeno B7-H1/metabolismo , ADN Cruciforme/química , Animales , Línea Celular Tumoral , Ratones Endogámicos BALB C , Nanoestructuras/química
18.
Molecules ; 26(4)2021 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-33670668

RESUMEN

Designing of nanomaterials has now become a top-priority research goal with a view to developing specific applications in the biomedical fields. In fact, the recent trends in the literature show that there is a lack of in-depth reviews that specifically highlight the current knowledge based on the design and production of nanomaterials. Considerations of size, shape, surface charge and microstructures are important factors in this regard as they affect the performance of nanoparticles (NPs). These parameters are also found to be dependent on their synthesis methods. The characterisation techniques that have been used for the investigation of these nanomaterials are relatively different in their concepts, sample preparation methods and obtained results. Consequently, this review article aims to carry out an in-depth discussion on the recent trends on nanomaterials for biomedical engineering, with a particular emphasis on the choices of the nanomaterials, preparation methods/instruments and characterisations techniques used for designing of nanomaterials. Key applications of these nanomaterials, such as tissue regeneration, medication delivery and wound healing, are also discussed briefly. Covering this knowledge gap will result in a better understanding of the role of nanomaterial design and subsequent larger-scale applications in terms of both its potential and difficulties.


Asunto(s)
Tecnología Biomédica/tendencias , Nanoestructuras/química , Sistemas de Liberación de Medicamentos , Dispersión Dinámica de Luz , Humanos , Nanoestructuras/ultraestructura , Medicina Regenerativa , Electricidad Estática
19.
Food Chem ; 352: 129323, 2021 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33691210

RESUMEN

In this study, functional snacks with addition of nanoenapsuated resveratrol were prepared to evaluate the nutraceutical and physical properties. The nanoencapsulated resveratrol was prepared from horse-chestnut (HRP), water-chestnut (WRP) and lotus-stem starch particles (LRP) and added to the wheat flour at the level of 0.4% for preparation of snacks by extrusing process. After extrusion, 43-53% and 5.42% of resveratrol was retained in snacks containing encapsulated and free resveratrol (FRP), respectively. The HRP, WRP and LRP showed significantly less peak viscosities and less elastic behaviour than native product (NP) which can influence the human sensory perception. The shift of few peaks towards higher wavelength and presence of additional peaks at 1384, 1229, 1513 and 1613 cm-1 depicts change in molecular pattern and presence of resveratrol in functional snacks. The functional snacks containing encapsulated resveratrol showed significantly higher antioxidant, anti-diabetic and anti-obesity properties than snacks containing no or free resveratrol.


Asunto(s)
Nanoestructuras/química , Resveratrol/química , Resveratrol/farmacología , Bocadillos , Fármacos Antiobesidad/química , Fármacos Antiobesidad/farmacología , Antioxidantes/química , Antioxidantes/farmacología , Cápsulas , Harina/análisis , Humanos , Hipoglucemiantes/química , Hipoglucemiantes/farmacología , Gusto , Triticum/química , Viscosidad
20.
Carbohydr Polym ; 260: 117769, 2021 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-33712127

RESUMEN

Periodontal defect poses a significant challenge in orthopedics. Guided Bone Regeneration (GBR) membrane is considered as one of the most successful methods applied to reconstruct alveolar bone and then to achieve periodontal defect repair/regeneration. In this paper, a novel polyamide-6/chitosan@nano-hydroxyapatite/polyamide-6 (PA6/CS@n-HA/PA6) bilayered tissue guided membranes by combining a solvent casting and an electrospinning technique was designed. The developed PA6/CS@n-HA/PA6 composites were characterized by a series of tests. The results show that n-HA/PA6 and electrospun PA6/CS layers are tightly bound by molecular interaction and chemical bonding, which enhances the bonding strength between two distinct layers. The porosity and adsorption average pore diameter of the PA6/CS@n-HA/PA6 membranes are 36.90 % and 22.61 nm, respectively. The tensile strength and elastic modulus of PA6/CS@n-HA/PA6 composites are 1.41 ± 0.18 MPa and 7.15 ± 1.09 MPa, respectively. In vitro cell culture studies demonstrate that PA6/CS@n-HA/PA6 bilayered scaffolds have biological safety, good bioactivity, biocompatibility and osteoconductivity.


Asunto(s)
Regeneración Ósea , Caprolactama/análogos & derivados , Quitosano/química , Durapatita/química , Membranas Artificiales , Nanoestructuras/química , Polímeros/química , Animales , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Regeneración Ósea/efectos de los fármacos , Caprolactama/química , Adhesión Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Línea Celular , Supervivencia Celular/efectos de los fármacos , Ratones , Nanofibras/química , Nanoestructuras/toxicidad , Porosidad , Propiedades de Superficie , Resistencia a la Tracción
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