Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.454
Filtrar
1.
Molecules ; 26(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34443412

RESUMO

Palmarosa essential oil (PEO) is an alternative to synthetic fungicides to control the contamination by food-deteriorating fungi, such as Aspergillus nomius. Nonetheless, the low long-term stability and volatility hamper its utilization. Thus, this study aimed to develop nanostructured lipid carriers (NLCs) containing PEO to improve its stability and consequently prolong the activity against A. nomius. A mixture design was applied to find the best preparation conditions for antifungal activity. The characterization analyses included size measurements, zeta potential (ζ-potential), entrapment efficiency (EE), and antifungal activity (by inhibition of mycelial growth (IMG) and/or in situ test (pre-contaminated Brazil nuts) tests). The nanocarriers presented particle sizes smaller than 300 nm, homogeneous size distribution, ζ-potential of -25.19 to -41.81 mV, and EE between 73.6 and 100%. The formulations F5 and F10 showed the highest IMG value (98.75%). Based on the regression model, three optimized formulations (OFs) were tested for antifungal activity (IMG and in situ test), which showed 100% of inhibition and prevented the deterioration of Brazil nuts by A. nomius. The preliminary stability test showed the maintenance of antifungal activity and physicochemical characteristics for 90 days. These results suggest a promising system as a biofungicide against A. nomius.


Assuntos
Aspergillus/efeitos dos fármacos , Cymbopogon/química , Portadores de Fármacos/química , Nanoestruturas/química , Óleos Voláteis/farmacologia , Antifúngicos/farmacologia , Bertholletia/microbiologia , Composição de Medicamentos , Cromatografia Gasosa-Espectrometria de Massas , Testes de Sensibilidade Microbiana , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Eletricidade Estática
2.
Int J Mol Sci ; 22(15)2021 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-34360734

RESUMO

Biomimetic design provides novel opportunities for enhancing and functionalizing biomaterials. Here we created a zirconia surface with cactus-inspired meso-scale spikes and bone-inspired nano-scale trabecular architecture and examined its biological activity in bone generation and integration. Crisscrossing laser etching successfully engraved 60 µm wide, cactus-inspired spikes on yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) with 200-300 nm trabecular bone-inspired interwoven structures on the entire surface. The height of the spikes was varied from 20 to 80 µm for optimization. Average roughness (Sa) increased from 0.10 µm (polished smooth surface) to 18.14 µm (80 µm-high spikes), while the surface area increased by up to 4.43 times. The measured dimensions of the spikes almost perfectly correlated with their estimated dimensions (R2 = 0.998). The dimensional error of forming the architecture was 1% as a coefficient of variation. Bone marrow-derived osteoblasts were cultured on a polished surface and on meso- and nano-scale hybrid textured surfaces with different spike heights. The osteoblastic differentiation was significantly promoted on the hybrid-textured surfaces compared with the polished surface, and among them the hybrid-textured surface with 40 µm-high spikes showed unparalleled performance. In vivo bone-implant integration also peaked when the hybrid-textured surface had 40 µm-high spikes. The relationships between the spike height and measures of osteoblast differentiation and the strength of bone and implant integration were non-linear. The controllable creation of meso- and nano-scale hybrid biomimetic surfaces established in this study may provide a novel technological platform and design strategy for future development of biomaterial surfaces to improve bone integration and regeneration.


Assuntos
Materiais Biomiméticos , Diferenciação Celular/efeitos dos fármacos , Nanoestruturas/química , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Zircônio , Animais , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Cactaceae , Masculino , Nanoestruturas/ultraestrutura , Osteoblastos/citologia , Ratos , Ratos Sprague-Dawley , Zircônio/química , Zircônio/farmacologia
3.
Nat Commun ; 12(1): 4849, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34381032

RESUMO

Although various artificial protein nanoarchitectures have been constructed, controlling the transformation between different protein assemblies has largely been unexplored. Here, we describe an approach to realize the self-assembly transformation of dimeric building blocks by adjusting their geometric arrangement. Thermotoga maritima ferritin (TmFtn) naturally occurs as a dimer; twelve of these dimers interact with each other in a head-to-side manner to generate 24-meric hollow protein nanocage in the presence of Ca2+ or PEG. By tuning two contiguous dimeric proteins to interact in a fully or partially side-by-side fashion through protein interface redesign, we can render the self-assembly transformation of such dimeric building blocks from the protein nanocage to filament, nanorod and nanoribbon in response to multiple external stimuli. We show similar dimeric protein building blocks can generate three kinds of protein materials in a manner that highly resembles natural pentamer building blocks from viral capsids that form different protein assemblies.


Assuntos
Nanoestruturas/química , Proteínas/química , Cálcio/química , Ferritinas/química , Nanoestruturas/ultraestrutura , Nanotecnologia , Polietilenoglicóis/química , Multimerização Proteica , Thermotoga maritima
4.
Molecules ; 26(15)2021 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-34361740

RESUMO

There is a challenging need for the development of new alternative nanostructures that can allow the coupling and/or encapsulation of therapeutic/diagnostic molecules while reducing their toxicity and improving their circulation and in-vivo targeting. Among the new materials using natural building blocks, peptides have attracted significant interest because of their simple structure, relative chemical and physical stability, diversity of sequences and forms, their easy functionalization with (bio)molecules and the possibility of synthesizing them in large quantities. A number of them have the ability to self-assemble into nanotubes, -spheres, -vesicles or -rods under mild conditions, which opens up new applications in biology and nanomedicine due to their intrinsic biocompatibility and biodegradability as well as their surface chemical reactivity via amino- and carboxyl groups. In order to obtain nanostructures suitable for biomedical applications, the structure, size, shape and surface chemistry of these nanoplatforms must be optimized. These properties depend directly on the nature and sequence of the amino acids that constitute them. It is therefore essential to control the order in which the amino acids are introduced during the synthesis of short peptide chains and to evaluate their in-vitro and in-vivo physico-chemical properties before testing them for biomedical applications. This review therefore focuses on the synthesis, functionalization and characterization of peptide sequences that can self-assemble to form nanostructures. The synthesis in batch or with new continuous flow and microflow techniques will be described and compared in terms of amino acids sequence, purification processes, functionalization or encapsulation of targeting ligands, imaging probes as well as therapeutic molecules. Their chemical and biological characterization will be presented to evaluate their purity, toxicity, biocompatibility and biodistribution, and some therapeutic properties in vitro and in vivo. Finally, their main applications in the biomedical field will be presented so as to highlight their importance and advantages over classical nanostructures.


Assuntos
Materiais Biocompatíveis/síntese química , Portadores de Fármacos/síntese química , Nanoestruturas/química , Peptídeos/síntese química , Técnicas de Síntese em Fase Sólida/métodos , Sequência de Aminoácidos , Animais , Materiais Biocompatíveis/farmacocinética , Portadores de Fármacos/farmacocinética , Composição de Medicamentos/métodos , Humanos , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Peptídeos/farmacocinética , Distribuição Tecidual
5.
Int J Mol Sci ; 22(13)2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-34202080

RESUMO

Alveolar macrophages are the first line of defense against intruding pathogens and play a critical role in cancer immunology. The Toll-like receptor (TLR) family mediates an important role in recognizing and mounting an immune response against intruding microbes. TLR-9 is a member of the intracellular TLR family, which recognizes unmethylated CG motifs from the prokaryotic genome. Upon its activation, TLR-9 triggers downstream of the MyD-88-dependent transcriptional activation of NF-κB, and subsequently results in abundant inflammatory cytokines expression that induces a profound inflammatory milieu. The present exploratory investigation aimed at elucidating the potency of schizophyllan for entrapping ODN 1826 (SPG-ODN 1826)-mediated stimulation of TLR-9 in provoking an inflammatory-type response in murine alveolar macrophages. Schizophyllan (SPG), a representative of the ß-glucan family, was used in the present study as a nanovehicle for endosomal trafficking of CpG ODN 1826. TEM analysis of SPG-ODN 1826 nanovehicles revealed that the prepared nanovehicles are spherical and have an average size of about 100 nm. Interestingly, SPG-ODN 1826 nanovehicles were competent in delivering their therapeutic payload within endosomes of murine alveolar macrophage (J774A.1) cells. Exposure of these nanovehicles within LPS stimulated J774A.1, resulted in a significant provocation of reactive oxygen species (ROS) (p < 0.01) in comparison to CpG ODN 1826 alone. Moreover, the formulated nanovehicles succeeded in generating a profound Th1-based cytokine profile constituted by enhanced expression of IFN-γ (p < 0.001) and IL-1ß (p < 0.001) inflammatory cytokines. These findings clearly indicated the immunostimulatory potential of SPG-ODN 1826 nanovehicles for inducing the Th1-type phenotype, which would certainly assist in skewing M2 phenotype into the much-desired M1 type during lung cancer.


Assuntos
Macrófagos Alveolares/imunologia , Macrófagos Alveolares/metabolismo , Nanoestruturas/química , Oligodesoxirribonucleotídeos/química , Sizofirano/química , Receptor Toll-Like 9/agonistas , Animais , Sobrevivência Celular , Citocinas/metabolismo , Endossomos , Imunofenotipagem , Mediadores da Inflamação/metabolismo , Ativação de Macrófagos/imunologia , Camundongos , Nanoestruturas/administração & dosagem , Nanoestruturas/ultraestrutura , Tamanho da Partícula
6.
Nat Commun ; 12(1): 4494, 2021 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-34301935

RESUMO

Self-assembling peptides have shown tremendous potential in the fields of material sciences, nanoscience, and medicine. Because of the vast combinatorial space of even short peptides, identification of self-assembling sequences remains a challenge. Herein, we develop an experimental method to rapidly screen a huge array of peptide sequences for self-assembling property, using the one-bead one-compound (OBOC) combinatorial library method. In this approach, peptides on beads are N-terminally capped with nitro-1,2,3-benzoxadiazole, a hydrophobicity-sensitive fluorescence molecule. Beads displaying self-assembling peptides would fluoresce under aqueous environment. Using this approach, we identify eight pentapeptides, all of which are able to self-assemble into nanoparticles or nanofibers. Some of them are able to interact with and are taken up efficiently by HeLa cells. Intracellular distribution varied among these non-toxic peptidic nanoparticles. This simple screening strategy has enabled rapid identification of self-assembling peptides suitable for the development of nanostructures for various biomedical and material applications.


Assuntos
Nanofibras/química , Nanoestruturas/química , Biblioteca de Peptídeos , Peptídeos/química , Dicroísmo Circular , Técnicas de Química Combinatória/métodos , Células HeLa , Ensaios de Triagem em Larga Escala/métodos , Humanos , Ligação de Hidrogênio , Microscopia Eletrônica de Transmissão , Nanofibras/ultraestrutura , Nanoestruturas/ultraestrutura , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
7.
Theranostics ; 11(14): 6717-6734, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34093849

RESUMO

Rationale: Osteoporotic patients suffer symptoms of excessive osteoclastogenesis and impaired osteogenesis, resulting in a great challenge to treat osteoporosis-related bone defects. Based on the positive effect of rare earth elements on bone metabolism and bone regeneration, we try to prove the hypothesis that the La3+ dopants in lanthanum-substituted MgAl layered double hydroxide (La-LDH) nanohybrid scaffolds simultaneously activate osteogenesis and inhibit osteoclastogenesis. Methods: A freeze-drying technology was employed to construct La-LDH nanohybrid scaffolds. The in vitro osteogenic and anti-osteoclastogenic activities of La-LDH nanohybrid scaffolds were evaluated by using ovariectomized rat bone marrow stromal cells (rBMSCs-OVX) and bone marrow-derived macrophages (BMMs) as cell models. The in vivo bone regeneration ability of the scaffolds was investigated by using critical-size calvarial bone defect model of OVX rats. Results: La-LDH nanohybrid scaffolds exhibited three-dimensional macroporous structure, and La-LDH nanoplates arranged perpendicularly on chitosan organic matrix. The La3+ dopants in the scaffolds promote proliferation and osteogenic differentiation of rBMSCs-OVX by activating Wnt/ß-catenin pathway, leading to high expression of ALP, Runx-2, COL-1 and OCN genes. Moreover, La-LDH scaffolds significantly suppressed RANKL-induced osteoclastogenesis by inhibiting NF-κB signaling pathway. As compared with the scaffolds without La3+ dopants, La-LDH scaffolds provided more favourable microenvironment to induce new bone in-growth along macroporous channels. Conclusion: La-LDH nanohybrid scaffolds possessed the bi-directional regulation functions on osteogenesis and osteoclastogenesis for osteoporotic bone regeneration. The modification of La3+ dopants in bone scaffolds provides a novel strategy for osteoporosis-related bone defect healing.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Lantânio/farmacologia , Nanoestruturas/química , Osteogênese/efeitos dos fármacos , Osteoporose/tratamento farmacológico , Tecidos Suporte/química , Animais , Regeneração Óssea/genética , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Dioxigenases/metabolismo , Modelos Animais de Doenças , Feminino , Humanos , Lantânio/química , Macrófagos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , NF-kappa B/metabolismo , Nanoestruturas/ultraestrutura , Osteocalcina/metabolismo , Osteogênese/genética , Osteoporose/metabolismo , Ligante RANK/farmacologia , Ratos , Ratos Sprague-Dawley , Tomografia Computadorizada por Raios X , Via de Sinalização Wnt/efeitos dos fármacos , Via de Sinalização Wnt/genética
8.
Nat Commun ; 12(1): 3529, 2021 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-34112802

RESUMO

The abundance of plant-derived proteins, as well as their biodegradability and low environmental impact make them attractive polymeric feedstocks for next-generation functional materials to replace current petroleum-based systems. However, efforts to generate functional materials from plant-based proteins in a scalable manner have been hampered by the lack of efficient methods to induce and control their micro and nanoscale structure, key requirements for achieving advantageous material properties and tailoring their functionality. Here, we demonstrate a scalable approach for generating mechanically robust plant-based films on a metre-scale through controlled nanometre-scale self-assembly of water-insoluble plant proteins. The films produced using this method exhibit high optical transmittance, as well as robust mechanical properties comparable to engineering plastics. Furthermore, we demonstrate the ability to impart nano- and microscale patterning into such films through templating, leading to the formation of hydrophobic surfaces as well as structural colour by controlling the size of the patterned features.


Assuntos
Nanoestruturas/química , Proteínas de Plantas/química , Polímeros/química , Propriedades de Superfície , Hidrogéis/química , Interações Hidrofóbicas e Hidrofílicas , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanoestruturas/ultraestrutura , Solubilidade , Solventes/química , Soja/química , Soja/metabolismo , Água/química
9.
Nat Commun ; 12(1): 3902, 2021 06 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162863

RESUMO

Self-assembly of proteins holds great promise for the bottom-up design and production of synthetic biomaterials. In conventional approaches, designer proteins are pre-programmed with specific recognition sites that drive the association process towards a desired organized state. Although proven effective, this approach poses restrictions on the complexity and material properties of the end-state. An alternative, hierarchical approach that has found wide adoption for inorganic systems, relies on the production of crystalline nanoparticles that become the building blocks of a next-level assembly process driven by oriented attachment (OA). As it stands, OA has not yet been observed for protein systems. Here we employ cryo-transmission electron microscopy (cryoEM) in the high nucleation rate limit of protein crystals and map the self-assembly route at molecular resolution. We observe the initial formation of facetted nanocrystals that merge lattices by means of OA alignment well before contact is made, satisfying non-trivial symmetry rules in the process. As these nanocrystalline assemblies grow larger we witness imperfect docking events leading to oriented aggregation into mesocrystalline assemblies. These observations highlight the underappreciated role of the interaction between crystalline nuclei, and the impact of OA on the crystallization process of proteins.


Assuntos
Aldose-Cetose Isomerases/química , Nanoestruturas/química , Proteínas Recombinantes/química , Aldose-Cetose Isomerases/genética , Aldose-Cetose Isomerases/metabolismo , Microscopia Crioeletrônica , Cristalização , Cristalografia por Raios X , Cinética , Modelos Moleculares , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Mutação Puntual , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura
10.
Nat Struct Mol Biol ; 28(7): 573-582, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34158638

RESUMO

SARS-CoV-2 ORF3a is a putative viral ion channel implicated in autophagy inhibition, inflammasome activation and apoptosis. 3a protein and anti-3a antibodies are found in infected patient tissues and plasma. Deletion of 3a in SARS-CoV-1 reduces viral titer and morbidity in mice, suggesting it could be an effective target for vaccines or therapeutics. Here, we present structures of SARS-CoV-2 3a determined by cryo-EM to 2.1-Å resolution. 3a adopts a new fold with a polar cavity that opens to the cytosol and membrane through separate water- and lipid-filled openings. Hydrophilic grooves along outer helices could form ion-conduction paths. Using electrophysiology and fluorescent ion imaging of 3a-reconstituted liposomes, we observe Ca2+-permeable, nonselective cation channel activity, identify mutations that alter ion permeability and discover polycationic inhibitors of 3a activity. 3a-like proteins are found across coronavirus lineages that infect bats and humans, suggesting that 3a-targeted approaches could treat COVID-19 and other coronavirus diseases.


Assuntos
Microscopia Crioeletrônica , Nanoestruturas , SARS-CoV-2 , Proteínas Viroporinas/química , Proteínas Viroporinas/ultraestrutura , Animais , Cálcio/metabolismo , Quirópteros/virologia , Coronaviridae , Eletrofisiologia , Fluorescência , Humanos , Transporte de Íons , Lipossomos , Modelos Moleculares , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Fases de Leitura Aberta , Imagem Óptica , Reprodutibilidade dos Testes , SARS-CoV-2/química , SARS-CoV-2/ultraestrutura , Homologia de Sequência , Proteínas Virais/química , Proteínas Virais/ultraestrutura , Proteínas Viroporinas/antagonistas & inibidores
11.
Nat Commun ; 12(1): 2941, 2021 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-34011929

RESUMO

Myelin insulates neuronal axons and enables fast signal transmission, constituting a key component of brain development, aging and disease. Yet, myelin-specific imaging of macroscopic samples remains a challenge. Here, we exploit myelin's nanostructural periodicity, and use small-angle X-ray scattering tensor tomography (SAXS-TT) to simultaneously quantify myelin levels, nanostructural integrity and axon orientations in nervous tissue. Proof-of-principle is demonstrated in whole mouse brain, mouse spinal cord and human white and gray matter samples. Outcomes are validated by 2D/3D histology and compared to MRI measurements sensitive to myelin and axon orientations. Specificity to nanostructure is exemplified by concomitantly imaging different myelin types with distinct periodicities. Finally, we illustrate the method's sensitivity towards myelin-related diseases by quantifying myelin alterations in dysmyelinated mouse brain. This non-destructive, stain-free molecular imaging approach enables quantitative studies of myelination within and across samples during development, aging, disease and treatment, and is applicable to other ordered biomolecules or nanostructures.


Assuntos
Sistema Nervoso Central/metabolismo , Sistema Nervoso Central/ultraestrutura , Bainha de Mielina/metabolismo , Bainha de Mielina/ultraestrutura , Tomografia Computadorizada por Raios X/métodos , Animais , Axônios/metabolismo , Axônios/ultraestrutura , Encéfalo/metabolismo , Encéfalo/ultraestrutura , Sistema Nervoso Central/diagnóstico por imagem , Pré-Escolar , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas da Mielina/metabolismo , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Neuroimagem/métodos , Estudo de Prova de Conceito , Espalhamento a Baixo Ângulo , Medula Espinal/metabolismo , Medula Espinal/ultraestrutura
12.
Int J Mol Sci ; 22(6)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799554

RESUMO

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.


Assuntos
Bactérias/química , Celulose/farmacologia , Cosméticos/química , Química Verde , Polissacarídeos Bacterianos/farmacologia , Celulose/química , Celulose/isolamento & purificação , Cosméticos/farmacologia , Humanos , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Polissacarídeos Bacterianos/química , Polissacarídeos Bacterianos/isolamento & purificação , Pele/efeitos dos fármacos , Higiene da Pele/métodos
13.
Int J Nanomedicine ; 16: 2405-2417, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33814907

RESUMO

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.


Assuntos
Bronquiectasia/tratamento farmacológico , Ciprofloxacina/uso terapêutico , Portadores de Fármacos/química , Lipídeos/química , Nanoestruturas/química , Administração por Inalação , Antibacterianos/administração & dosagem , Antibacterianos/farmacologia , Quitosana/química , Ciprofloxacina/administração & dosagem , Portadores de Fármacos/administração & dosagem , Liberação Controlada de Fármacos , Inaladores de Pó Seco , Fibrose , Cinética , Lipossomos , Pulmão , Testes de Sensibilidade Microbiana , Nanoestruturas/ultraestrutura , Tamanho da Partícula , Eletricidade Estática
14.
Nat Commun ; 12(1): 2025, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795690

RESUMO

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.


Assuntos
Dicroísmo Circular/métodos , DNA/química , Ouro/química , Nanotubos/química , DNA/genética , DNA/ultraestrutura , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Microscopia Eletrônica de Transmissão , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Estereoisomerismo
15.
Nat Commun ; 12(1): 2294, 2021 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863889

RESUMO

A systematic and robust approach to generating complex protein nanomaterials would have broad utility. We develop a hierarchical approach to designing multi-component protein assemblies from two classes of modular building blocks: designed helical repeat proteins (DHRs) and helical bundle oligomers (HBs). We first rigidly fuse DHRs to HBs to generate a large library of oligomeric building blocks. We then generate assemblies with cyclic, dihedral, and point group symmetries from these building blocks using architecture guided rigid helical fusion with new software named WORMS. X-ray crystallography and cryo-electron microscopy characterization show that the hierarchical design approach can accurately generate a wide range of assemblies, including a 43 nm diameter icosahedral nanocage. The computational methods and building block sets described here provide a very general route to de novo designed protein nanomaterials.


Assuntos
Ciência dos Materiais/métodos , Complexos Multiproteicos/ultraestrutura , Nanoestruturas/ultraestrutura , Cristalografia por Raios X , Simulação de Dinâmica Molecular , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Proteínas Recombinantes/ultraestrutura , Software
16.
ACS Appl Mater Interfaces ; 13(11): 13781-13791, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33703880

RESUMO

Ubiquitous biological processes exhibit the ability to achieve spontaneous directionally guided droplet transport. Maskless three-dimensional (3D) fabrication of various miniature bionic structures, a method applicable to various materials, is subject to processing method limitations. This remains a large obstacle to realizing self-driven, continuous, and controllable unidirectional liquid spreading. Thus, we present a flexible maskless 3D method for fabricating bionic unidirectional liquid spreading surfaces by using a phase spatially shaped femtosecond laser. The laser can be transformed from having Gaussian distributions to having 3D bionic structure field distributions. Furthermore, we fabricated Syntrichia caninervis bionic structures with a spiculate end for unidirectional water spreading; 1 µL droplets had a 16 mm flow length on Si surfaces when the S. caninervis single structure was 34 (length), 8 (width), and 12 µm (height). Furthermore, various bionic structures-Nepenthes, cactus, and moth structures-were fabricated on Si, SiO2, and Ti. We also demonstrated the measurability of two-dimensional (S-shaped) curved flows on Si wafers as well as 3D curved flows on a Ti pipe turning 120° within 2320 ms. Our method can realize high-efficiency maskless 3D processing of various materials and structures (especially asymmetric structures); it is both flexible and fast, effectively expanding the processing capacity of micro-/nanostructures on patterned surfaces. This is of great significance to various domains such as microfluids, fog collection, and chemical reaction control.


Assuntos
Materiais Biomiméticos/química , Nanoestruturas/química , Dióxido de Silício/química , Silício/química , Titânio/química , Anisotropia , Biônica , Briófitas/química , Lasers , Microfluídica , Nanoestruturas/ultraestrutura , Propriedades de Superfície , Água/química
17.
Int J Biol Macromol ; 180: 432-438, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33705834

RESUMO

Drug-delivery technology is an effective way to promote drug absorption and efficacy. Mesoporous hollow silica material and small-molecule drug ibuprofen were used as a carrier model and as model drug, respectively. By quantum chemical calculation (density functional theory and frontier orbital theory), it was found that the content of geminal silanols on the material surface played a decisive role in the release of the different drugs. The rough hollow materials are easily adsorbed and have a large loading capacity, and so we fabricated a mesoporous hollow silica material (R-nCHMSNs) with a rough surface and rich geminal silanols by using hydroxyl-rich nanocellulose as a template. The content and types of hydroxyl groups on the material surface were studied by 29Si NMR. The loading and delivery of ibuprofen and lysozyme were studied in detail. Materials with rich geminal silanols exhibited excellent delivery properties for different drugs, which shows great potential and research value for drug delivery.


Assuntos
Celulose/química , Sistemas de Liberação de Medicamentos/métodos , Nanosferas/química , Nanoestruturas/química , Silício/química , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/química , Anti-Inflamatórios não Esteroides/farmacocinética , Celulose/ultraestrutura , Liberação Controlada de Fármacos , Ibuprofeno/administração & dosagem , Ibuprofeno/química , Ibuprofeno/farmacocinética , Espectroscopia de Ressonância Magnética , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Nanosferas/ultraestrutura , Nanoestruturas/ultraestrutura , Porosidade , Espectrofotometria , Difração de Raios X
18.
Int J Biol Macromol ; 181: 275-290, 2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-33781811

RESUMO

Nanocellulose is a promising "green" nanomaterial that has recently gained scientific interest because of its excellent characteristics, such as less risks of toxicity, biocompatibility, biodegradability, recyclability, and tunable surface features. Initially, three nanocellulose types (i.e., bacterial nanocellulose, nanocrystals, and nanofibers) and their potential biotechnological production routes have been discussed in detail. Contemporary studies are discussed in the development of nanocellulose aerogels, responsive hydrogels, injectable hydrogels/implants, and magnetic nanocellulose. Moreover, the development of hydrogels and potential crosslinking agents for the induction of desired properties has been described. Studies have revealed that the release kinetics of nanocellulosic gels/hydrogels varies from few minutes to several days depending on the given physicochemical conditions. However, such systems provide sustained drug release properties, so they are considered "smart" systems. Recent studies on controlled drug delivery systems have demonstrated their considerable potential for the next-generation transport of therapeutic drugs to target sites via various administration routes. This review presents the selection of appropriate sources and processing methodologies for the development of target nanocellulose types. It explains the potential challenges and opportunities and recommends future research directions about the smart delivery of therapeutic drugs.


Assuntos
Celulose/química , Sistemas de Liberação de Medicamentos , Hidrogéis/química , Nanoestruturas/química , Nanotecnologia/métodos , Concentração de Íons de Hidrogênio , Nanoestruturas/ultraestrutura
19.
J Vis Exp ; (169)2021 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-33749671

RESUMO

On-surface synthesis has recently been regarded as a promising approach for the generation of new molecular structures. It has been particularly successful in the synthesis of graphene nanoribbons, nanographenes and intrinsically reactive and instable, yet attractive species. It is based on the combination of solution chemistry aimed at preparation of appropriate molecular precursors for further ultra-high vacuum surface assisted transformations. This approach also owes its success to an incredible development of characterization techniques, such as scanning tunneling/atomic force microscopy and related methods, which allow detailed, local characterization at atomic scale. While the surface-assisted synthesis can provide molecular nanostructures with outstanding precision, down to single atoms, it suffers from basing on metallic surfaces and often limited yield. Therefore, the extension of the approach away from metals and the struggle to increase productivity seem to be significant challenges toward wider applications. Herein, we demonstrate the on-surface synthesis approach for generation of non-planar nanographenes, which are synthesized through a combination of solution chemistry and sequential surface-assisted processes, together with the detailed characterization by scanning probe microscopy methods.


Assuntos
Grafite/química , Microscopia de Força Atômica/métodos , Nanoestruturas/química , Monóxido de Carbono/química , Ouro/química , Grafite/síntese química , Hidrogenação , Nanoestruturas/ultraestrutura , Porosidade , Soluções , Análise Espectral , Propriedades de Superfície , Vácuo
20.
Int J Nanomedicine ; 16: 1805-1817, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33692623

RESUMO

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.


Assuntos
DNA/química , Técnicas de Transferência de Genes , Glioma/terapia , Nanoestruturas/química , RNA Interferente Pequeno/administração & dosagem , Apoptose/efeitos dos fármacos , Aptâmeros de Nucleotídeos/química , Morte Celular , Linhagem Celular Tumoral , Sobrevivência Celular , Regulação para Baixo , Endocitose , Inativação Gênica , Glioma/patologia , Células Endoteliais da Veia Umbilical Humana , Humanos , Nanoestruturas/ultraestrutura , Oligodesoxirribonucleotídeos/química , Fosfoproteínas/metabolismo , RNA Interferente Pequeno/genética , Proteínas de Ligação a RNA/metabolismo , Survivina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...