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1.
Artif Organs ; 2020 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-33169400

RESUMO

Tubular polymer scaffolds based on tissue engineering techniques have been studied as potential alternatives for vascular regeneration implants. The blood vessels of the cardiovascular system are mainly fibrous, composed of collagen (Col) and elastin (El), and its inner layer consists of endothelial cells. In this work, Col and El were combined with polyurethane (PU), a biocompatible synthetic polymer, and Rotary Jet Spinning, a new and highly productive technique, to produce fibrous scaffolds. The scaffolds produced at 18,000 rpm presented homogeneous, bead-free, and solvent-free fibers. The blend formation between PU-Col-El was identified by chemical composition analysis and enhanced thermal stability up to 324 °C. The hydrophilic nature of the scaffold was revealed by its low contact angle. Cell viability of human umbilical vein endothelial cells (HUVEC) with the scaffold was proven for 72 h. The combined strategy of Rotary Jet Spinning with a polymer blend containing Col and El was verified as an effective and promising alternative to obtain tubular scaffolds for tissue engineering on a large scale production.

2.
Nanomedicine ; : 102331, 2020 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-33181272

RESUMO

AgNPs@Chitosan and Co3O4-NPs@Chitosan were fabricated with Salvia hispanica. Results showed MZI values of 5 and 30mm for Co3O4-NPs- and AgNPs@Chitosan against S.aureus, and 15 and 21mm for Co3O4-NPs- and AgNPs@Chitosan against E.coli (24hours, 20µg/mL), respectively. MTT assays showed up to (80%, 90%), (71%, 75%) and (91%, 94%) mammalian cell viability for the green synthesized, chemically synthesized AgNPs and green synthesized AgNPs@Chitosan for HEK-293 and PC12 cells, respectively, and (70%, 71%), (59%, 62%) and (88%, 73%) for the related Co3O4-NPs (24hours, 20µg/mL). The photocatalytic activities showed dye degradation after 135 and 105minutes for AgNPs@Chitosan and Co3O4-NPs@Chitosan, respectively. FESEM results showed differences in particle sizes (32±3.0nm for the AgNPs and 41±3.0nm for the Co3O4NPs) but AFM results showed lower roughness of the AgNPs@Chitosan (7.639±0.85nm) compared to Co3O4NPs@Chitosan (9.218±0.93nm), which resulted in potential biomedical applications.

4.
Int J Nanomedicine ; 15: 7079-7096, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33061369

RESUMO

Here, bismuth-based nanomaterials (Bi-based NMs) are introduced as promising theranostic agents to enhance image contrast as well as for the therapeutic gain for numerous diseases. However, understanding the interaction of such novel developed nanoparticles (NPs) within a biological environment is a requisite for the translation of any promising agent from the lab bench to the clinic. This interaction delineates the fate of NPs after circulation in the body. In an ideal setting, a nano-based therapeutic agent should be eliminated via the renal clearance pathway, meanwhile it should have specific targeting to a diseased organ to reach an effective dose and also to overcome off-targeting. Due to their clearance pathway, biodistribution patterns and pharmacokinetics (PK), Bi-based NMs have been found to play a determinative role to pass clinical approval and they have been investigated extensively in vivo to date. In this review, we expansively discuss the possible toxicity induced by Bi-based NMs on cells or organs, as well as biodistribution profiles, PK and the clearance pathways in animal models. A low cytotoxicity of Bi-based NMs has been found in vitro and in vivo, and along with their long-term biodistribution and proper renal clearance in animal models, the translation of Bi-based NMs to the clinic as a useful novel theranostic agent is promising to improve numerous medical applications.

5.
Int J Nanomedicine ; 15: 8201-8215, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33122906

RESUMO

Background: One major limitation of cancer chemotherapy is a failure to specifically target a tumor, potentially leading to side effects such as systemic cytotoxicity. In this case, we have generated a cancer cell-targeting nanoparticle-liposome drug delivery system that can be activated by near-infrared laser light to enable local photo-thermal therapy and the release of chemotherapeutic agents, which could achieve combined therapeutic efficiency. Methods: To exploit the magnetic potential of iron oxide, we prepared and characterized citric acid-coated iron oxide magnetic nanoparticles (CMNPs) and encapsulated them into thermo-sensitive liposomes (TSLs). The chemotherapeutic drug, doxorubicin (DOX), was then loaded into the CMNP-TSLs, which were coated with an antibody against the epidermal growth factor receptor (EGFR), cetuximab (CET), to target EGFR-expressing breast cancer cells in vitro and in vivo studies in mouse model. Results: The resulting CET-DOX-CMNP-TSLs were stable with an average diameter of approximately 120 nm. First, the uptake of TSLs into breast cancer cells increased by the addition of the CET coating. Next, the viability of breast cancer cells treated with CET-CMNP-TSLs and CET-DOX-CMNP-TSLs was reduced by the addition of photo-thermal therapy using near-infrared (NIR) laser irradiation. What is more, the viability of breast cancer cells treated with CMNP-TSLs plus NIR was reduced by the addition of DOX to the CMNP-TSLs. Finally, photo-thermal therapy studies on tumor-bearing mice subjected to NIR laser irradiation showed that treatment with CMNP-TSLs or CET-CMNP-TSLs led to an increase in tumor surface temperature to 44.7°C and 48.7°C, respectively, compared with saline-treated mice body temperature ie, 35.2°C. Further, the hemolysis study shows that these nanocarriers are safe for systemic delivery. Conclusion: Our studies revealed that a combined therapy of photo-thermal therapy and targeted chemotherapy in thermo-sensitive nano-carriers represents a promising therapeutic strategy against breast cancer.

8.
Int J Nanomedicine ; 15: 6239-6245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32904074

RESUMO

Background: As a key component in artificial intelligence computing, a transistor design is updated here as a potential alternative candidate for artificial synaptic behavior implementation. However, further updates are needed to better control artificial synaptic behavior. Here, an updated channel-electrode transistor design is proposed as an artificial synapse device; this structure is different from previously published designs by other groups. Methods: A semiconductor characterization system was used in order to simulate the artificial synaptic behavior and a scanning electron microscope was used to characterize the device structure. Results: It was found that the electrode added to the transistor channel had a strong impact on the representative transmission behavior of such artificial synaptic devices, such as excitatory postsynaptic current (EPSC) and the paired-pulse facilitation (PPF) index. Conclusion: These behaviors were tuned effectively and the impact of the channel electrode is explained by the combined effects of the joint channel electrode and conventional gate. The voltage dependence of such oxide devices suggests more capability to emulate various synaptic behaviors for numerous medical and non-medical applications. This is extremely helpful for future neuromorphic computational system implementation.


Assuntos
Eletrofisiologia/instrumentação , Neurônios/fisiologia , Sinapses/fisiologia , Inteligência Artificial , Eletrodos , Eletrofisiologia/métodos , Desenho de Equipamento , Ouro/química , Microscopia Eletrônica de Varredura/instrumentação , Níquel/química , Semicondutores , Sinapses/química , Transmissão Sináptica
9.
J Biomed Nanotechnol ; 16(5): 553-582, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919478

RESUMO

Successful gene therapy depends on the design of effective gene delivery systems. A gene delivery system is considered a powerful tool for the release of genetic material within cells resulting in a change in cell functions and protein production. The release of genes in a controlled manner by using appropriate carriers facilitates their release without side effects and increases the expression of genes at the released site. It is expected that significant changes in the combination of several genes and drugs can be provided by developing treatment systems sensitive to different stimuli such as redox potential, pH variations, temperature gradients, light irradiation, and enzyme activity. The most important advantages for the release of genes and stimuli-responsive therapeutics include delivering vectors locally, reducing side effects and causing no toxicity to distant tissues while at the same time reducing the immune response to the vectors. In this review, we aim to discuss different types of gene carriers involved in the controlled transfer of nucleic acids (non-viral inorganic and organic nanoparticles (NPs) and virus-like particles (VLPs)) as well as the simultaneous transfer of several genes and/or drugs into cells or different tissues, providing for an efficient and safe treatment of numerous diseases.


Assuntos
Nanoestruturas , Portadores de Fármacos , Sistemas de Liberação de Medicamentos , Técnicas de Transferência de Genes , Nanopartículas
10.
Nanomedicine ; 30: 102297, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32931927

RESUMO

This study investigated the synthesis of Pd nanoparticles (NPs) using a high-gravity technique mediated by Salvia hispanica leaf extracts. Biological assays confirmed their antibacterial activity against gram positive (S. aureus) and gram negative (E. coli) bacteria with significant antioxidant activity in comparison with the standards as well as low cellular toxicity on PC12 and HEK293 cell lines. To the best of our knowledge, this study can be considered as the first investigation of Pd-NPs synthesized by Salvia hispanica leaf extracts assisted by a high-gravity technique. In addition, the mentioned green synthesis procedure led to the formation of nanoparticles with considerable antibacterial properties independent of the morphology and texture of the green media of these nanoparticles. Considering the increasing rate of antimicrobial resistant bacteria deaths worldwide, this study introduces a novel green synthesis method and non-antibiotic nanoparticle which should be studied for a wide range of medical applications.

11.
Nanomedicine (Lond) ; 15(24): 2399-2410, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32945246

RESUMO

Nephrotoxicity, neurotoxicity and multidrug resistance in tumor cells can result from platinum-based anticancer (PBA) agents which can be reduced by nano formulations. Recently, novel formulations based on liposomes and cubosomes have been described as efficient strategies to overcome nephrotoxicity, ototoxicity, neurotoxicity, cardiotoxicity, hematological toxicities, hepatotoxicity and gastrointestinal toxicity as well as multidrug resistance. The co-delivery of anticancer agents concomitant with PBAs via biocompatible and biodegradable smart liposomes and cubosomes can augment therapeutic results of chemotherapy as well as radiotherapy owing to their high accessibility of surface and internal modification. For this purpose, surface, bilayer or core sections of these formulations can be functionalized by pure PBAs or modified PBAs. In this review, recent significant advances and challenges related to various liposomal and cubosomal formulations of PBA are presented in order to emphasize suitable formulations for anticancer applications with critical thoughts provided on how the field can progress.

12.
J Biomed Nanotechnol ; 16(4): 456-466, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32970978

RESUMO

Among different forms of metallic nanoparticles (NPs), zinc oxide (ZnO) NPs with a very special bandgap of 3.37 eV and considerable binding energy of excitation (60 meV at room temperature), have been classified as high-tech nanoparticles. This study aimed to synthesize ZnO NPs using the extract from Salvia hispanica leaves. The synthesized nanoparticles were fully characterized and the photocatalytic activity was evaluated through the degradation of methylene blue. Additionally, the potential in vitro biological activities of such ZnO NPs in terms of their antibacterial activity were determined, as well as their antioxidant (30 minutes), antiviral (48 hours) and mammalian cell viability properties (48 and 72 hours). This study is the first investigation into the synthesis of such green ZnO NPs mediated by this plant extract, in which both photocatalytic and biomedical properties were found to be promising. The IC50 values for the antibacterial activities were found to be around 17.4 µg mL-1 and 28.5 µg mL-1 for S. aureus and E. coli, respectively, and the antioxidant activity was comparable with the standard BHT. However, the H1N1 inhibition rate using the present green ZnO NPs was lower than oseltamivir (up to about 40% for ZnO NPs and above 90% for oseltamivir) which was expected since it is a drug, but was higher than many synthetic nanoparticles reported in the literature. In addition, the mammalian cell viability assay showed a higher than 80% cellular viability in the presence of 5, 10 and 20 µg mL-1 nanoparticles, and showed a higher than 50% cellular viability in the presence of 50 and 75 µg mL-1 nanoparticles. In this manner, this study showed that these green ZnO NPs should be studied for a wide range of medical applications.


Assuntos
Vírus da Influenza A Subtipo H1N1 , Nanopartículas Metálicas , Salvia , Animais , Antibacterianos/farmacologia , Antioxidantes/farmacologia , Sobrevivência Celular , Escherichia coli , Química Verde , Mamíferos , Testes de Sensibilidade Microbiana , Staphylococcus aureus , Difração de Raios X , Óxido de Zinco/farmacologia
13.
J Biomed Nanotechnol ; 16(4): 520-530, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32970983

RESUMO

Here, an unprecedented synthesis method for nickel oxide nanoparticles (NiO-NPs) was facilitated using Salvia hispanica leaf extracts with the assistance of a high gravity rotating packed bed (RPB) system that enabled fast mass transfer and molecular mixing. The synthesized nanoparticles were anchored on the surface of biodegradable chitosan nanobeads and their photocatalytic activity was evaluated by the degradation of methylene blue. Additionally, the potential biological activities of NiO-NPs in terms of antibacterial (Staphylococcus aureus and Escherichia coli for 24 hours), cytotoxicity (using the PC12 cell line for 24 and 72 hours), and antioxidant activities (based on the discoloration of the methanolic solution of DPPH) were assessed. This novel approach for NiO-NPs@Chitosan synthesis as mediated by a renewable plant extract and facilitated by a high-gravity method, led to the greener synthesis of nanoparticles with significant antibacterial and photocatalytic properties.


Assuntos
Hipergravidade , Nanopartículas Metálicas , Antibacterianos/farmacologia , Química Verde , Testes de Sensibilidade Microbiana , Níquel , Extratos Vegetais , Staphylococcus aureus
14.
Mater Sci Eng C Mater Biol Appl ; 116: 111149, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32806280

RESUMO

Organic-inorganic hybrid coatings deposited on different types of metallic alloys have shown outstanding anticorrosive performance. The incorporation of osteoconductive additives such as hydroxyapatite (HA) and ß-tricalcium phosphate (ß-TCP) into organic-inorganic hybrid coatings is promising to improve the osseointegration and corrosion resistance of Ti6Al4V alloys, which are the most widely used metallic orthopedic and dental implant materials today. Therefore, this study evaluated the capability of poly(methyl methacrylate) (PMMA)-TiO2 and PMMA-ZrO2 hybrid coatings modified with HA and ß-TCP to act as bioactive and corrosion protection coatings for Ti6Al4V alloys. In terms of cell growth and mineralization, osteoblast viability, Ca+2 deposition and alkaline phosphatase assays revealed a significant improvement for the HA and ß-TCP modified coatings, compared to the bare alloy. This can be explained by an increase in nanoscale roughness and associated higher surface free energy, which lead to enhanced protein adsorption to promote osteoblast attachment and functions on the coatings. The effect of HA and ß-TCP additives on the anticorrosive efficiency was studied by electrochemical impedance spectroscopy (EIS) in a simulated body fluid (SBF) solution. The coatings presented a low-frequency impedance modulus of up to 430 GΩ cm2, 5 decades higher than the bare Ti6Al4V alloy. These findings provide clear evidence of the beneficial role of HA and ß-TCP modified hybrid coatings, improving both the biocompatibility and corrosion resistance of the Ti6Al4V alloy.

16.
Nanomaterials (Basel) ; 10(8)2020 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-32824491

RESUMO

Angiogenesis (or the development of new blood vessels) is a key event in tissue engineering and regenerative medicine; thus, a number of biomaterials have been developed and combined with stem cells and/or bioactive molecules to produce three-dimensional (3D) pro-angiogenic constructs. Among the various biomaterials, electrospun nanofibrous scaffolds offer great opportunities for pro-angiogenic approaches in tissue repair and regeneration. Nanofibers made of natural and synthetic polymers are often used to incorporate bioactive components (e.g., bioactive glasses (BGs)) and load biomolecules (e.g., vascular endothelial growth factor (VEGF)) that exert pro-angiogenic activity. Furthermore, seeding of specific types of stem cells (e.g., endothelial progenitor cells) onto nanofibrous scaffolds is considered as a valuable alternative for inducing angiogenesis. The effectiveness of these strategies has been extensively examined both in vitro and in vivo and the outcomes have shown promise in the reconstruction of hard and soft tissues (mainly bone and skin, respectively). However, the translational of electrospun scaffolds with pro-angiogenic molecules or cells is only at its beginning, requiring more research to prove their usefulness in the repair and regeneration of other highly-vascularized vital tissues and organs. This review will cover the latest progress in designing and developing pro-angiogenic electrospun nanofibers and evaluate their usefulness in a tissue engineering and regenerative medicine setting.

17.
Int J Nanomedicine ; 15: 5417-5432, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801697

RESUMO

Introduction: Green-based materials have been increasingly studied to circumvent off-target cytotoxicity and other side-effects from conventional chemotherapy. Materials and Methods: Here, cellulose fibers (CF) were isolated from rice straw (RS) waste by using an eco-friendly alkali treatment. The CF network served as an anticancer drug carrier for 5-fluorouracil (5-FU). The physicochemical and thermal properties of CF, pure 5-FU drug, and the 5-FU-loaded CF (CF/5-FU) samples were evaluated. The samples were assessed for in vitro cytotoxicity assays using human colorectal cancer (HCT116) and normal (CCD112) cell lines, along with human nasopharyngeal cancer (HONE-1) and normal (NP 460) cell lines after 72-hours of treatment. Results: XRD and FTIR revealed the successful alkali treatment of RS to isolate CF with high purity and crystallinity. Compared to RS, the alkali-treated CF showed an almost fourfold increase in surface area and zeta potential of up to -33.61 mV. SEM images illustrated the CF network with a rod-shaped structure and comprised of ordered aggregated cellulose. TGA results proved that the thermal stability of 5-FU increased within the drug carrier. Based on UV-spectroscopy measurements for 5-FU loading into CF, drug loading encapsulation efficiency was estimated to be 83 ±0.8%. The release media at pH 7.4 and pH 1.2 showed a maximum drug release of 79% and 46%, respectively, over 24 hours. In cytotoxicity assays, CF showed almost no damage, while pure 5-FU killed most of the both normal and cancer cells. Impressively, the drug-loaded sample of CF/5-FU at a 250 µg/mL concentration demonstrated a 58% inhibition against colorectal cancer cells, but only a 23% inhibition against normal colorectal cells. Further, a 62.50 µg/mL concentration of CF/5FU eliminated 71% and 39% of nasopharyngeal carcinoma and normal nasopharyngeal cells, respectively. Discussion: This study, therefore, showed the strong potential anticancer activity of the novel CF/5-FU formulations, warranting their further investigation.


Assuntos
Celulose/química , Portadores de Fármacos/química , Fluoruracila/administração & dosagem , Fluoruracila/farmacologia , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/farmacocinética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Fluoruracila/farmacocinética , Células HCT116 , Humanos , Neoplasias Nasofaríngeas/tratamento farmacológico , Oryza/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Termogravimetria , Difração de Raios X
18.
Int J Nanomedicine ; 15: 5279-5288, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32801691

RESUMO

Introduction: Today, a new paradigm has emerged for cancer treatment introducing combination therapies. Doxil, a liposomal doxorubicin serving as a chemotherapeutic agent, is an effective immunogenic killer of cancer cells. Anti-CTLA-4 has been approved for the treatment of some cancers, including melanoma, but side effects have limited its therapeutic potential. Methods: In this study, two approaches were utilized to increase treatment efficiency and decrease the side effects of anti-CTLA-4, combining it with chemotherapy and encapsulation in a PEGylated liposome. A different sequence of anti-CTLA-4 and Doxil was assessed in combination therapy using non-liposomal and liposomal anti-CTLA-4. Results: Our results showed that liposomal anti-CTLA-4 reduced the size of established tumors and increased survival in comparison with non-liposomal anti-CTLA-4 in a well-established B16 mouse melanoma model. In combination therapy with Doxil, only the administration of anti-CTLA-4 before Doxil showed synergism in both non-liposomal and liposomal form and increased the CD8+/regulatory T cell ratio. Discussion: In summary, our results demonstrate the potential of utilizing a nanocarrier system for the delivery of checkpoint blockers, such as anti-CTLA-4 which further showed potential in a combination therapy, especially when administered before chemotherapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Antígeno CTLA-4/antagonistas & inibidores , Melanoma Experimental/tratamento farmacológico , Animais , Antineoplásicos Imunológicos/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Antígeno CTLA-4/imunologia , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Feminino , Lipossomos/química , Camundongos Endogâmicos C57BL , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/química , Linfócitos T Reguladores/efeitos dos fármacos
19.
ACS Appl Mater Interfaces ; 12(29): 33219-33228, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32603082

RESUMO

Cartilage damage caused by aging, repeated overloading, trauma, and diseases can result in chronic pain, inflammation, stiffness, and even disability. Unlike other types of tissues (bone, skin, muscle, etc.), cartilage tissue has an extremely weak regenerative capacity. Currently, the gold standard surgical treatment for repairing cartilage damage includes autografts and allografts. However, these procedures are limited by insufficient donor sources and the potential for immunological rejection. After years of development, engineered tissue now provides a valuable artificial replacement for tissue regeneration purposes. Three-dimensional (3D) bioprinting technologies can print customizable hierarchical structures with cells. The objective of the current work was to prepare a 3D-printed three-layer gradient scaffold with lysine-functionalized rosette nanotubes (RNTK) for improving the chondrogenic differentiation of adipose-derived mesenchymal stem cells (ADSCs). Specifically, biologically inspired RNTKs were utilized in our work because they have unique surface chemistry and biomimetic nanostructure to improve cell adhesion and growth. Different ratios of gelatin methacrylate (GelMA) and poly(ethylene glycol) diacrylate (PEGDA) were printed into a three-layer GelMA-PEGDA gradient scaffold using a stereolithography-based printer, followed by coating with RNTKs. The pores and channels (∼500 µm) were observed in the scaffold. It was found that the population of ADSCs on the GelMA-PEGDA-RNTK scaffold increased by 34% compared to the GelMA-PEGDA scaffold (control). Moreover, after 3 weeks of chondrogenic differentiation, collagen II, glycosaminoglycan, and total collagen synthesis on the GelMA-PEGDA-RNTK scaffold significantly respectively increased by 59%, 71%, and 60%, as compared to the control scaffold. Gene expression of collagen II α1, SOX 9, and aggrecan in the ADSCs growing on the GelMA-PEGDA-RNTK scaffold increased by 79%, 52%, and 47% after 3 weeks, compared to the controls, respectively. These results indicated that RNTKs are a promising type of nanotubes for promoting chondrogenic differentiation, and the present 3D-printed three-layer gradient GelMA-PEGDA-RNTK scaffold shows considerable promise for future cartilage repair and regeneration.

20.
J Mater Sci Mater Med ; 31(8): 63, 2020 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-32696134

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

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