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1.
Mol Biol Rep ; 51(1): 310, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38372812

RESUMO

BACKGROUND: Lung cancer is a common and deadly disease. Chemotherapy is the most common treatment, which inhibits cancer cell growth. Pemetrexed (PMX) is often used with other drugs. Environmental stress can affect regulatory non-coding RNAs such as MicroRNAs that modify gene expression. This study investigates the effect of PMX on the hsa-miR-320a-3p expression in the Calu-6 lung cancer cell line. METHODS AND RESULT: Calu-6 cells were cultured in an incubator with 37 °C, 5% CO2, and 98% humidity. The MTT test was performed to determine the concentration of PMX required to inhibit 50% of cell growth. To examine growth inhibition and apoptosis, release of lactate dehydrogenase (LDH), cell assays and caspase 3 and 7 enzyme activity were used. Finally, molecular studies were conducted to compare the expression of hsa-miR-320a-3p and genes including VDAC1, DHFR, STAT3, BAX and BCL2 before and after therapy. RESULTS: According to a study, it has been observed that PMX therapy significantly increases LDH release after 24 h. The study found that PMX's IC50 on Calu-6 is 8.870 µM. In addition, the treated sample showed higher expression of hsa-miR-320a-3p and BAX, while the expression of VDAC1, STAT3, DHFR and BCL2 decreased compared to the control sample. CONCLUSION: According to the findings of the current research, hsa-miR-320a-3p seems to have the potential to play an important role in the development of novel approaches to the treatment of lung cancer.


Assuntos
Neoplasias Pulmonares , MicroRNAs , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Pemetrexede/farmacologia , Regulação para Cima/genética , Proteína X Associada a bcl-2/genética , MicroRNAs/genética , Linhagem Celular
3.
Nanotechnology ; 34(15)2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36638529

RESUMO

Here, we prepared a magnetic nanocomposite system composed of a cluster of magnetite nanoparticles coated with silica shell (MSNPs) with an average diameter of 140 ± 20 nm and conjugated with CD9 antibody (AntiCD9) using different strategies including adsorption or chemical conjugation of antibody molecules to either aminated MSNPs (AMSNPs) or carboxylated MSNPs (CMSNPs). Then, MSNPs were employed to isolate exosomes from ultracentrifuge-enriched solution, PC3 cell-culture medium, or exosome-spiked simulated plasma samples. Quantitative tests using nanoparticle-tracking analysis confirmed antibody-covalently conjugated MSNPs, i.e. the AntiCD9-AMSNPs and AntiCD9-CMSNPs enabled >90% recovery of exosomes. Additionally, the exosomes isolated with AntiCD9-CMSNPs showed higher recovery efficiency compared to the AntiCD9-AMSNPs. For both nanoadsorbents, lower protein impurities amounts were obtained as compared to that of exosomes isolated by ultracentrifugation and Exocib kit. The mean diameter assessment of the isolated exosomes indicates that particles isolated by using AntiCD9-AMSNPs and AntiCD9-CMSNPs have smaller sizes (136 ± 2.64 nm and 113 ± 11.53 nm, respectively) than those obtained by UC-enriched exosomes (140.9 ± 1.6 nm) and Exocib kit (167 ± 10.53 nm). Such promising results obtained in the isolation of exosomes recommend magnetic nanocomposite as an efficient tool for the simple and fast isolation of exosomes for diagnosis applications.


Assuntos
Exossomos , Anticorpos/metabolismo , Exossomos/química , Fenômenos Magnéticos , Proteínas/análise , Ultracentrifugação/métodos , Nanocompostos/química
4.
ACS Appl Bio Mater ; 6(1): 191-202, 2023 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-36580633

RESUMO

In this study, we prepared various anionic magnetic adsorbents through the carboxyl functionalization of core/shell-structured Fe3O4/SiO2 (FS) particles by either succinic anhydride (FSC), low-molecular-weight (MW 1800) polyacrylic acid (PAA) (FSP1), or high-molecular-weight (MW 100,000) PAA (FSP2), and then, investigated the effect of the structure of adsorbents and operational parameters on their performance for the lysozyme separation. The type and size of functional molecules have significant effects on the surface concentration of functional carboxyl groups onto the adsorbent particles (increase in the order of FSP2 > FSP1 > FSC), and consequently on the adsorption efficiency (AE) (∼100, 98, and 62%, respectively) and adsorption capacity (AC) (∼1000, 980, and 621 mg·g-1, respectively) of the adsorbents. However, the loss of the antibacterial activity of separated lysozyme molecules due to the molecular conformational change increased in the order of FSP2 > FSP1 = FSC, as compared to the free lysozyme. The application of basic buffer solutions for the elution of adsorbed enzyme molecules resulted in more adverse effects on the enzyme activity. The obtained results recommend that FSP1 can be used as a suitable anionic adsorbent for the isolation of positively charged proteins, owing to its high adsorption capacity, excellent reusability, and structural stability, as well as the high purity, structural stability, and activity recovery of the isolated proteins.


Assuntos
Muramidase , Nanocompostos , Muramidase/química , Dióxido de Silício/química , Magnetismo , Nanocompostos/química , Fenômenos Magnéticos
5.
Enzyme Microb Technol ; 154: 109974, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34933175

RESUMO

The emergence of antibiotic resistant bacteria because of the antibiotics abusement was the motivation to develop the effective alternatives to traditional antibiotics. Hence, various lysozyme corona were prepared through the physical and covalent attachment of lysozyme molecules onto either the bare or carboxyl-functionalized mesoporous silica particles. The prepared samples were characterized by STEM, TGA/DTA, zeta potential, FTIR, UV-vis and CD spectroscopic methods. All the prepared lysozyme-coated particles exhibited an efficient antibacterial activity against Listeria monocytogenes, as a case study, in vitro with no cytotoxicity. The minimal inhibition concentration (MIC) of the lysozyme-physically adsorbed bare and carboxyl-functionalized mesoporous silica nanoparticles (L-MS and L-ads-CMS, respectively) and the lysozyme-covalently attached carboxyl-functionalized MS particles (L-cov-CMS) was 2, 5.3 and 1.7 folds lower than that of the free lysozyme, respectively. Additionally, for the first time, it was reported that the pretreatment of lysozyme corona of L-ads-CMS through inducing a pH-shock can lead to the enhancement of antibacterial properties thereof. This behavior was associated to the controlled release of the immobilized lysozyme molecules and their conformational stability. These natural antibacterial lysozyme-coated silica nanoparticles showing the "pH-shock enhanced activity" could be of utmost interest for design of the highly active enzyme-modified nanoparticles.


Assuntos
Nanopartículas , Dióxido de Silício , Concentração de Íons de Hidrogênio , Muramidase , Porosidade
6.
Mater Sci Eng C Mater Biol Appl ; 128: 112316, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34474867

RESUMO

To develop a nanoparticle-based vaccine against necrotic enteritis, a chimeric antigen (rNA) consisting of the main antigens of Clostridium perfringens, NetB, and Alpha toxin, was prepared. Then, the rNA molecules were loaded onto the functionalized mesoporous silica nanoparticles (MSNPs) using physical adsorption or covalent conjugation methods. The characterization of synthesized nanoparticles was performed by scanning electron microscopy, dynamic light scattering, zeta potential measurement, Fourier transform infrared spectroscopy, and thermogravimetry techniques. The results revealed that the spherical nanoparticles with an average diameter of 90 ±â€¯12 nm and suitable surface chemistries are prepared. MSNPs-based formulations did not show any significant toxicity on the chicken embryo fibroblast cells. The results of the challenge experiments using subcutaneous or oral administration of the as-prepared formulations in the animal model showed that the as-prepared nanosystems, similar to those formulated with a commercial adjuvant (Montanide), present stronger humoral immune responses as compared to that of the free proteins. It was also indicated that the best protection is obtained in groups vaccinated with MSNPs-based nanovaccine, especially those who orally received covalently conjugated nanovaccine candidates. These results recommend that the MSNPs-based formulated chimeric proteinous vaccine candidates can be considered as an effective immunizing system for the oral vaccination of poultry against gastrointestinal infectious diseases.


Assuntos
Toxinas Bacterianas , Infecções por Clostridium , Enterite , Nanopartículas , Doenças das Aves Domésticas , Vacinas , Animais , Anticorpos Antibacterianos , Embrião de Galinha , Galinhas , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Enterite/prevenção & controle , Enterite/veterinária , Doenças das Aves Domésticas/prevenção & controle , Dióxido de Silício
7.
Biomed Pharmacother ; 140: 111755, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34044282

RESUMO

Lung cancer is known as the second leading cause of cancer death. Finding ways to detect early-stage lung cancer can remarkably increase the survival rate. Biomarkers such as microRNAs can be helpful in cancer diagnosis, predicting its prognosis, and patients' chances of survival. Numerous studies have confirmed the correlation between microRNA expression and the likelihood of patients surviving after treatment. Consequently, it is necessary to study the expression profile of microRNAs during and after treatment. Oncolytic virotherapy and nanotherapy are two neoteric methods that use various vectors to deliver microRNAs into cancer cells. Although these treatments have not yet entered into the clinical trials, much progress has been made in this area. Analyzing the expression profile of microRNAs after applying nanotherapy and oncolytic virotherapy can evaluate the effectiveness of these methods. This review refers to the studies conducted about these two approaches. The advantages and disadvantages of these methods in delivery and affecting microRNA expression patterns are discussed below.


Assuntos
Antineoplásicos/administração & dosagem , Neoplasias Pulmonares/terapia , MicroRNAs/administração & dosagem , Nanopartículas/administração & dosagem , Terapia Viral Oncolítica , Animais , Humanos , Neoplasias Pulmonares/genética , Nanomedicina
8.
Ultrason Sonochem ; 73: 105507, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33756435

RESUMO

Sonoporation, ultrasound-mediated membrane perforation can potentially puncture plasma membrane and rigid cell wall on presumably reversible basis which benefit gene transfection and plant biotechnology. Herein, positively charged poly-ethyleneimine (PEI)-coated mesoporous silica nanoparticles (MSNs) with an average diameter of 100 ± 8.7 nm was synthesized for GUS-encoding plasmid delivery into the suspended tobacco cells using the ultrasound treatment. The overall potential of PEI-MSN for DNA adsorption was measured at 43.43 µg DNA mg-1 PEI-MSNs. It was shown that high level of sonoporation may adversely upset the cell viability. Optimal conditions of ultrasonic treatment are obtained as 8 min at 3 various intensities of 160, 320 and 640 W. Histochemical staining assay was used to follow the protein expression. It was shown that PEI-coated MSNs efficiently transfer the GUS-encoding plasmid DNA into the tobacco cells. The results of this study showed that ultrasonic treatment provides an economical and straightforward approach for gene transferring into the plant cells without any need to complicated devices and concerns about safety issues.


Assuntos
Técnicas de Transferência de Genes , Nanopartículas/química , Células Vegetais/metabolismo , Polietilenoimina/química , Dióxido de Silício/química , Sonicação/métodos , Porosidade
9.
Anal Methods ; 12(28): 3670-3681, 2020 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-32701088

RESUMO

In the past few years graphene quantum dots (GQDs) have been used as a signaling agent for medical diagnosis. They can be modified and labeled with different macromolecules to give them potential to be attached to a specific target. Herein GQDs were labeled with an antibody which is specific for cancer-derived exosomes, isolated from blood serum by using a specialized PCL-gelatin core-shell NFM. This membrane showed excellent sensitivity for isolating exosomes from a complex mixture such as serum, and the GQD-antibody complex detected the isolated exosomes with great sensitivity. The final results allow this method to be considered as one that can be used to quantify the concentration of a desired analyte in a mixture.


Assuntos
Análise Química do Sangue , Exossomos , Grafite , Nanofibras , Neoplasias , Pontos Quânticos , Análise Química do Sangue/métodos , Grafite/química , Humanos , Nanofibras/química , Neoplasias/diagnóstico , Pontos Quânticos/química , Sensibilidade e Especificidade
10.
Biotechnol Lett ; 42(4): 597-603, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31950407

RESUMO

OBJECTIVES: The yeast cells were coated with Fe3O4 magnetic nanoparticles and employed as biocatalyst for the microbial biotransformation of benzaldehyde into L-phenylacetylcarbinol (L-PAC). RESULTS: Saccharomyces cerevisiae CEN.PK113-7D yeast cells were coated with magnetic nanoparticles to facilitate the cells separation process. Transmission electron microscopy, powder XRD diffraction, and vibrating sample magnetometer were used to characterize magnetic nanoparticles and magnetic nanoparticle-coated yeast cells. Then the reusability of magnetically recoverable cells in production of L-PAC was investigated. Results show that coating yeast cells with magnetic nanoparticles does not affect their size and structure. Coated cells were also used in seven consecutive batch cycles and no significant reduction for L-PAC titer was observed in any of the cycles. CONCLUSION: Coating yeast cells with magnetic nanoparticles enabled rapid separation and reuse of cells in several successive batch cycle without affecting their ability to produce L-PAC.


Assuntos
Acetona/análogos & derivados , Benzaldeídos/metabolismo , Nanopartículas de Magnetita/microbiologia , Saccharomyces cerevisiae/crescimento & desenvolvimento , Acetona/metabolismo , Técnicas de Cultura Celular por Lotes , Biocatálise , Biotransformação , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Difração de Pó , Saccharomyces cerevisiae/metabolismo , Difração de Raios X
11.
Mater Sci Eng C Mater Biol Appl ; 106: 110259, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31753381

RESUMO

Polymeric hydrogel-based 3D scaffolds are well-known structures, being used for cultivation and differentiation of stem cells. However, scalable systems that provide a native-like microenvironment with suitable biological and physical properties are still needed. Incorporation of nanomaterials into the polymeric systems is expected to influence the physical properties of the structure but also the stem cells fate. Here, alginate/gelatin hydrogel beads incorporated with mesoporous silica nanoparticles (MSNs) (average diameter 80.9 ±â€¯10 nm) and various surface chemistries were prepared. Human adipose-derived mesenchymal stem cells (hASCs) were subsequently encapsulated into the alginate/gelatin/silica hydrogels. Incorporation of amine- and carboxyl-functionalized MSNs (A-MSNs and C-MSNs) significantly enhances the stability of the hydrogel beads. In addition, the expression levels of Nanog and OCT4 imply that the incorporation of A-MSNs into the alginate/gelatin beads significantly improves the proliferation and the stemness of encapsulated hASCs. Importantly, our findings show that the presence of A-MSNs slightly suppresses in vivo inflammation. In contrast, the results of marker gene expression analyses indicate that cultivation of hASCs in alginate beads incorporated with C-MSNs (10% w/w) leads to a heterogeneously differentiated population of the cells, i.e., osteocytes, chondrocytes, and adipocytes, which is not appropriate for both cell culture and differentiation applications.


Assuntos
Técnicas de Cultura de Células/métodos , Hidrogéis/química , Nanopartículas/química , Dióxido de Silício/química , Tecido Adiposo/citologia , Alginatos/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Técnicas de Cultura de Células/instrumentação , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Gelatina/química , Humanos , Hidrogéis/farmacologia , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Proteína Homeobox Nanog/metabolismo , Fator 3 de Transcrição de Octâmero/metabolismo , Porosidade , Ratos , Ratos Wistar , Alicerces Teciduais/química
12.
Iran J Biotechnol ; 17(2): e2108, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31457057

RESUMO

BACKGROUND: Magnetic separation using magnetic nanoparticles can be used as a simple method to isolate desulfurizing bacteria from a biphasic oil/water system. OBJECTIVES: Magnetite nanoparticles were applied to coat the surface of Rhodococcus erythropolis IGTS8 and Rhodococcus erythropolis FMF desulfurizing bacterial cells, and the viability and reusability of magnetite-coated bacteria evaluated by using various methods. MATERIAL AND METHODS: Magnetite nanoparticles were synthesized through a reverse co-precipitation method. Glycine was added during and after the synthesis of magnetite nanoparticles to modify their surface and to stabilize the dispersion of the nanoparticles. The glycine-modified magnetite nanoparticles were immobilized on the surface of both oil-desulfurizing bacterial strains. Reusability of magnetite-coated bacterial cells was evaluated via assessing the desulfurization activity of bacteria via spectrophotometry using Gibb's assay, after the separation of bacterial cells from 96h-cultures with the application of external magnetic field. In addition, CFU and fluorescence imaging were used to investigate the viability of magnetite-coated and free bacterial cells. RESULTS: TEM micrographs showed that magnetite nanoparticles have the size approximately 5.35±1.13 nm. Reusability results showed that both magnetite-coated bacterial strains maintain their activity even after 5 × 96h-cycles. The viability results revealed glycine-modified magnetite nanoparticles did not negatively affect the viability of two bacterial strains R. erythropolis IGTS8 and R. erythropolis FMF. CONCLUSIONS: In conclusion, the glycine-modified magnetite nanoparticles have great capacity for immobilization and separation of desulfurizing bacteria from suspension.

13.
Colloids Surf B Biointerfaces ; 182: 110353, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31336281

RESUMO

Great advantages bestowed by mesoporous silica nanoparticles (MSNs) including high surface area, tailorable pore diameter and surface chemistry, and large pore volume render them as efficient tools in biomedical applications. Herein, MSNs with different surface chemistries were synthesized and investigated in terms of biocompatibility and their impact on the morphology of bone marrow-derived mesenchymal stem cells both in 2D and 3D culture systems. Bare MSNs (BMSNs) were synthesized by template removing method using tetraethylorthosilicate (TEOS) as a precursor. The as-prepared BMSNs were then used to prepare amine-functionalized (AMSNs), carboxyl-functionalized (CMSNs) and polymeric amine-functionalized (PMSNs) samples, consecutively. These nanoparticles were characterized by scanning electron microscopy, zeta potential measurement, dynamic light scattering, BET (Brunauer, Emmett, Teller) analysis, and FTIR technique. In a 3D culture system, stem cells were encapsulated in alginate hydrogel in which MSNs of different functionalities were incorporated. The results showed good biocompatibility for both BMSNs and AMSNs in 2D and 3D culture systems. For these samples, the viability of about 80% was acquired after 2 weeks of 3D culture. When compared to the control, CMSNs caused higher cell proliferation in the 2D culture; while they showed cytotoxic effects in the 3D culture system. Interestingly, polymeric amine-functionalized silica nanoparticles (PMSNs) resulted in disrupted morphology and very low viability in the 2D cell culture and even less viability in 3D environment in comparison to BMSNs and AMSNs. This significant decrease in cell viability was attributed to the higher uptake values of highly positively charged PMSNs by cells as compared to other MSNs. This up-regulated uptake was evaluated by using an inductively coupled plasma optical emission spectroscopy instrument (ICP-OES). These results uncover different interactions between cell and nanoparticles with various surface chemistries. Building on these results, new windows are opened for employing biocompatible nanoparticles such as BMSNs and AMSNs, even at high concentrations, as potential cargos for carrying required growth and/or differentiation factors for tissue engineering applications.


Assuntos
Materiais Biocompatíveis/síntese química , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanopartículas/química , Dióxido de Silício/química , Alginatos/química , Materiais Biocompatíveis/farmacologia , Técnicas de Cultura de Células , Encapsulamento de Células/métodos , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Hidrogéis , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Nanopartículas/ultraestrutura , Porosidade , Silanos/química , Dióxido de Silício/farmacologia , Eletricidade Estática , Relação Estrutura-Atividade , Propriedades de Superfície , Engenharia Tecidual/métodos
14.
Colloids Surf B Biointerfaces ; 175: 498-508, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30572158

RESUMO

Treatment of polymicrobial infections requires combination therapy with drugs that have different antimicrobial spectra and possibly work in synergy. However, the different pharmacokinetics and adverse side effects challenge the simultaneous delivery of multiple drugs at the appropriate concentrations to the site of infection. Formulation of multiple drugs in nano-carrier systems may improve therapeutic efficacy by increasing the local concentration and lowering the systemic concentration, leading to fewer side effects. In this study, we loaded polymyxin B and vancomycin on bare and carboxyl-modified mesoporous silica nanoparticles (B-MSNs and C-MSNs, respectively) to achieve simulataneous local delivery of antibiotics against Gram-positive and -negative bacteria. Polymyxin B adsorbed preferentially to nanoparticles compared to vancomycin. The total antibiotic loading was 563 µg and 453 µg per mg B-MSNs or C-MSNs, respectively. Both B-MSNs and C-MSNs loaded with antibiotics were effective against Gram-negative and Gram-positive bacteria. The antibiotics had synergistic interactions against Gram-negative bacteria, and the antimicrobial efficacy was higher for antibiotic-loaded C-MSNs compared to free antibiotics at the same concentration even though the cytotoxicity was lower. Our study shows that formulations of existing antibiotics in nanocarrier systems can improve their therapeutic efficiency, indicating that combination therapy with drug-loaded silica nanoparticles may provide a better treatment outcome for infections that require high concentrations of multiple drugs.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Materiais Biocompatíveis/farmacologia , Portadores de Fármacos/química , Sinergismo Farmacológico , Nanopartículas Metálicas/administração & dosagem , Dióxido de Silício/química , Antibacterianos/administração & dosagem , Antibacterianos/química , Materiais Biocompatíveis/química , Sobrevivência Celular , Células Cultivadas , Humanos , Nanopartículas Metálicas/química , Polimixina B/administração & dosagem , Polimixina B/química , Polimixina B/farmacologia , Porosidade , Vancomicina/administração & dosagem , Vancomicina/química , Vancomicina/farmacologia
15.
ACS Appl Mater Interfaces ; 10(41): 34924-34941, 2018 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-30226363

RESUMO

Despite the promise of hydrogel-based stem cell therapies in orthopedics, a significant need still exists for the development of injectable microenvironments capable of utilizing the  regenerative potential of donor cells. Indeed, the quest for biomaterials that can direct stem cells into bone without the need of external factors has been the "Holy Grail" in orthopedic stem cell therapy for decades. To address this challenge, we have utilized a combinatorial approach to screen over 63 nanoengineered hydrogels made from alginate, hyaluronic acid, and two-dimensional nanoclays. Out of these combinations, we have identified a biomaterial that can promote osteogenesis in the absence of well-established differentiation factors such as bone morphogenetic protein 2 (BMP2) or dexamethasone. Notably, in our "hit" formulations we observed a 36-fold increase in alkaline phosphate (ALP) activity and a 11-fold increase in the formation of mineralized matrix, compared to the control hydrogel. This induced osteogenesis was further supported by X-ray diffraction, scanning electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive X-ray spectroscopy. Additionally, the Montmorillonite-reinforced hydrogels exhibited high osteointegration as evident from the relatively stronger adhesion to the bone explants as compared to the control. Overall, our results demonstrate the capability of combinatorial and nanoengineered biomaterials to induce bone regeneration through osteoinduction of stem cells in a natural and differentiation-factor-free environment.


Assuntos
Alginatos/química , Calcificação Fisiológica , Hidrogéis/química , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Engenharia Tecidual/métodos , Proteína Morfogenética Óssea 2/metabolismo , Humanos , Ortopedia
16.
J Agric Food Chem ; 66(16): 4233-4243, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29621394

RESUMO

Antimicrobial agents, such as nisin, are used extensively in the food industry. Here, we investigated various approaches to load nisin onto mesoporous silica nanoparticles (MSNs, 92 ± 10 nm in diameter), to enhance its stability and sustained release. The morphology, size, and surface charge of the as-prepared nanoparticles were analyzed using scanning transmission electron microscopy, dynamic light scattering, and ζ potential measurement. Nisin was either physically adsorbed or covalently attached to the variously functionalized MSNs, with high loading capacities (>600 mg of nisin g-1 of nanoparticles). The results of antibacterial activity analysis of nisin against Staphylococcus aureus showed that, despite the very low antibacterial activity of nisin covalently conjugated onto MSNs, the physical adsorption of nisin onto the unfunctionalized nanoparticles enhances its antimicrobial activities under various conditions, with no significant cytotoxicity effects on mouse fibroblast L929 cells. In conclusion, MSNs can be recommended as suitable carriers for nisin under various conditions.


Assuntos
Antibacterianos/química , Antibacterianos/farmacologia , Portadores de Fármacos/química , Nisina/química , Nisina/farmacologia , Dióxido de Silício/química , Animais , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Estabilidade de Medicamentos , Difusão Dinâmica da Luz , Fibroblastos/efeitos dos fármacos , Camundongos , Nanopartículas/química , Tamanho da Partícula , Porosidade , Staphylococcus aureus/efeitos dos fármacos
17.
Artif Cells Nanomed Biotechnol ; 46(sup3): S1067-S1075, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30638077

RESUMO

In the present study, the application of mesoporous silica nanoparticles (MSNPs) loaded with recombinant EspA protein, an immunogen of enterohaemorrhagic E. coli, was investigated in the case of BALB/c mice immunization against the bacterium. MSNPs of 96.9 ± 15.9 nm in diameter were synthesized using template removing method. The immunization of mice was carried out orally and subcutaneously. Significant immune responses to the antigen were observed for the immunized mice when rEspA-loaded MSNPs were administered in both routes in comparison to that of the antigen formulated using a well-known adjuvant, i.e. Freund's. According to the titretitre of serum IL-4, the most potent humoral responses were observed when the mice were immunized subcutaneously with antigen-loaded MSNPs (244, 36 and 14 ng/dL of IL-4 in the serum of mice immunized subcutaneously or orally by antigen-loaded MSNPs, and subcutaneously by Freund's adjuvant formulated-antigen, respectively). However, the difference in serum IgG and serum IgA was not significant in mice subcutaneously immunized with antigen-loaded MSNPs and mice immunized with Freund's adjuvant formulated-antigen. Finally, the immunized mice were challenged orally by enterohaemorrhagic E. coli cells. The amount of bacterial shedding was significantly reduced in faecesfaeces of the animals immunized by antigen-loaded MSNPs in both subcutaneous and oral routes.


Assuntos
Escherichia coli O157/imunologia , Proteínas de Escherichia coli , Síndrome Hemolítico-Urêmica/prevenção & controle , Imunização , Nanopartículas , Dióxido de Silício , Animais , Anticorpos Antibacterianos/imunologia , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/imunologia , Proteínas de Escherichia coli/farmacologia , Feminino , Síndrome Hemolítico-Urêmica/imunologia , Síndrome Hemolítico-Urêmica/patologia , Camundongos , Camundongos Endogâmicos BALB C , Nanopartículas/química , Nanopartículas/uso terapêutico , Dióxido de Silício/química , Dióxido de Silício/farmacologia
18.
Int J Pharm ; 537(1-2): 148-161, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29278732

RESUMO

Polymyxin B is a polycationic antibiotic used as the last line treatment against antibiotic-resistant Gram negative bacteria. However, application of polymyxin B is limited because of its toxicity effects. Herein, we used bare and surface modified mesoporous silica nanoparticles (MSNs) with an average diameter of 72.29 ±â€¯8.17 nm as adsorbent for polymyxin B to improve its therapeutic properties. The polymyxin B adsorption onto MSN surfaces was explained as a function of pH, type of buffer and surface charge of nanoparticles, according to the ζ-potential of silica nanoparticles and adsorption kinetics results. The highest value of the adsorption capacity (about 401 ±â€¯15.38 mg polymyxin B/ g silica nanoparticles) was obtained for the bare nanoparticles in Tris buffer, pH 9. Release profiles of polymyxin B showed a sustained release pattern, fitting Power law and Hill models. The antibiotic molecules-loaded nanoparticles showed enhanced antibacterial activity compared to free antibiotic against different Gram negative bacteria. Biocompatibility evaluation results revealed that loading of polymyxin B onto MSNs can decrease the cytotoxicity effects of the drug by reducing ROS generation. Our results suggest that formulation of drugs by adsorption onto MSNs may offer a way forward to overcome the adverse effects of some antibiotics such as polymyxin B without compromising their antimicrobial properties.


Assuntos
Ânions/química , Antibacterianos/química , Materiais Biocompatíveis/química , Nanopartículas/química , Polimixina B/química , Dióxido de Silício/química , Adsorção/efeitos dos fármacos , Antibacterianos/administração & dosagem , Materiais Biocompatíveis/administração & dosagem , Linhagem Celular , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Portadores de Fármacos/química , Bactérias Gram-Negativas/efeitos dos fármacos , Células HEK293 , Células Hep G2 , Humanos , Tamanho da Partícula , Porosidade/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
19.
Adv Mater ; 29(8)2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27966826

RESUMO

Given their highly porous nature and excellent water retention, hydrogel-based biomaterials can mimic critical properties of the native cellular environment. However, their potential to emulate the electromechanical milieu of native tissues or conform well with the curved topology of human organs needs to be further explored to address a broad range of physiological demands of the body. In this regard, the incorporation of nanomaterials within hydrogels has shown great promise, as a simple one-step approach, to generate multifunctional scaffolds with previously unattainable biological, mechanical, and electrical properties. Here, recent advances in the fabrication and application of nanocomposite hydrogels in tissue engineering applications are described, with specific attention toward skeletal and electroactive tissues, such as cardiac, nerve, bone, cartilage, and skeletal muscle. Additionally, some potential uses of nanoreinforced hydrogels within the emerging disciplines of cyborganics, bionics, and soft biorobotics are highlighted.


Assuntos
Hidrogéis/química , Materiais Biocompatíveis , Cartilagem , Humanos , Engenharia Tecidual , Alicerces Teciduais , Suporte de Carga
20.
Langmuir ; 32(50): 13394-13402, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27993021

RESUMO

This study aimed to develop a drug carrier based on amine-functionalized mesoporous silica nanoparticles (AAS-MSNPs) for a poorly water-soluble drug, curcumin (CUR), and to study its effects on α-synuclein (α-Syn) fibrillation and cytotoxicity. Here, we show that AAS-MSNPs possess high values of loading efficiency and capacity (33.5% and 0.45 mg drug/mg MSNPs, respectively) for CUR. It is also revealed that α-Syn species interact strongly with the CUR-loaded AAS-MSNPs, leading to a significant inhibition of the fibrillation process. Furthermore, these samples reduce the toxic effects of CUR. However, drug-loaded AAS-MSNPs do not affect the cytotoxic properties of the formed fibrils considerably. In addition, CUR loaded onto AAS-MSNPs shows enhanced stability in comparison with that of the free drug. These remarkable properties introduce AAS-MSNPs as a promising tool for the formulation of poorly water-soluble drugs such as CUR.


Assuntos
Curcumina/química , Portadores de Fármacos , Nanopartículas , Dióxido de Silício , alfa-Sinucleína/antagonistas & inibidores , Aminas , Animais , Células PC12 , Ratos
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