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1.
Mol Biol Rep ; 51(1): 310, 2024 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-38372812

RESUMEN

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.


Asunto(s)
Neoplasias Pulmonares , MicroARNs , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Pemetrexed/farmacología , Regulación hacia Arriba/genética , Proteína X Asociada a bcl-2/genética , MicroARNs/genética , Línea Celular
2.
Nanotechnology ; 34(15)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36638529

RESUMEN

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.


Asunto(s)
Exosomas , Anticuerpos/metabolismo , Exosomas/química , Fenómenos Magnéticos , Proteínas/análisis , Ultracentrifugación/métodos , Nanocompuestos/química
3.
Biotechnol Lett ; 42(4): 597-603, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31950407

RESUMEN

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.


Asunto(s)
Acetona/análogos & derivados , Benzaldehídos/metabolismo , Nanopartículas de Magnetita/microbiología , Saccharomyces cerevisiae/crecimiento & desarrollo , Acetona/metabolismo , Técnicas de Cultivo Celular por Lotes , Biocatálisis , Biotransformación , Microscopía Electrónica de Transmisión , Tamaño de la Partícula , Difracción de Polvo , Saccharomyces cerevisiae/metabolismo , Difracción de Rayos X
4.
Langmuir ; 32(13): 3242-52, 2016 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-26986897

RESUMEN

A facile approach for the preparation of core-shell structured poly(acrylic acid) (PAA)-coated Fe3O4 cluster@SiO2 nanocomposite particles as the support materials for the lipase immobilization is reported. Low- or high-molecular-weight (1800 and 100,000, respectively) PAA molecules were covalently attached onto the surface of amine-functionalized magnetic silica nanoacomposite particles. The successful preparation of particles were verified by scanning transmission electron microscopy (STEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermogravimetric analysis (TGA), zeta potential measurement, and Fourier-transform infrared (FTIR) techniques. Once lipase is covalently immobilized onto the particles with an average diameter of 210 ± 50 nm, resulting from high binding sites concentrations on the low- and high-molecular-weight PAA-coated particles, high lipase immobilization efficiencies (86.2% and 89.9%, respectively), and loading capacities (786 and 816 mg g(-1), respectively) are obtained. Results from circular dichroism (CD) analysis and catalytic activity tests reveal an increase in the ß-sheet content of lipase molecules upon immobilization, along with an enhancement in their activities and stabilities. The lipases immobilized onto the low- and high-molecular-weight PAA-coated particles show maximum activities at 55 and 50 °C, respectively, which are ∼28% and ∼15% higher than that of the free lipase at its own optimum temperature (40 °C), respectively. The immobilized lipases exhibit excellent performance at broader temperature and pH ranges and high thermal and storage stabilities, as well as superior reusability. These prepared magnetic nanocomposite particles can be offered as suitable support materials for efficient immobilization of enzymes and improvement of the immobilized enzymes properties.

5.
Langmuir ; 32(50): 13394-13402, 2016 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-27993021

RESUMEN

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.


Asunto(s)
Curcumina/química , Portadores de Fármacos , Nanopartículas , Dióxido de Silicio , alfa-Sinucleína/antagonistas & inhibidores , Aminas , Animales , Células PC12 , Ratas
6.
Biotechnol Appl Biochem ; 60(3): 323-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23656694

RESUMEN

The application of Fe3 O4 nanoparticles to the separation of desulfurizing bacterial cells and their influence on the desulfurization activity and reusability of the two bacterial strains Rhodococcus erythropolis FMF and R. erythropolis IGTS8 were investigated. Magnetite nanoparticles were synthesized via the reverse coprecipitation method. Transmission electron microscopy (TEM) images showed that the magnetite nanoparticles had sizes of 5.35 ± 1.13 (F1 nanoparticles) and 8.74 ± 1.18 nm (F2 nanoparticles) when glycine was added during the synthesis of nanoparticles and when it was absent from the reaction mixture, respectively. Glycine was added after the synthesis of both F1 and F2 nanoparticles to stabilize the nanoparticle dispersion. TEM images of cells treated with magnetite nanoparticles indicated that F1 nanoparticles were immobilized on the surface of bacterial cells more evenly than the F2 nanoparticles. Desulfurization activities of the F1 magnetite nanoparticle-coated R. erythropolis FMF and R. erythropolis IGTS8 cells (with sulfur-removal percentage values of 70 ± 4 and 73 ± 3, respectively), as examined with the spectrophotometric Gibbs assay (based on dibenzothiophene degradation and sulfur-removal percentage), were not significantly different from those for the free bacterial cells (67 ± 3 and 69 ± 4, respectively). These results indicate that magnetite nanoparticles cannot affect the desulfurization activity of cells examined in this work. Isolation of bacterial cells from the suspension using a magnet and evaluation of desulfurization activity of separated cells showed that Fe3 O4 nanoparticles can provide a high-efficiency recovery of bacterial cells from a suspension, with the reused magnetite nanoparticle-coated bacterial cells being able to maintain their desulfurization activity efficiently.


Asunto(s)
Bacterias/metabolismo , Nanopartículas de Magnetita/microbiología , Rhodococcus/metabolismo , Azufre/metabolismo , Biomasa , Glicina/metabolismo , Tamaño de la Partícula
7.
ACS Appl Bio Mater ; 6(1): 191-202, 2023 01 16.
Artículo en Inglés | MEDLINE | ID: mdl-36580633

RESUMEN

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.


Asunto(s)
Muramidasa , Nanocompuestos , Muramidasa/química , Dióxido de Silicio/química , Magnetismo , Nanocompuestos/química , Fenómenos Magnéticos
8.
Enzyme Microb Technol ; 154: 109974, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34933175

RESUMEN

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.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Concentración de Iones de Hidrógeno , Muramidasa , Porosidad
9.
Ultrason Sonochem ; 73: 105507, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33756435

RESUMEN

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.


Asunto(s)
Técnicas de Transferencia de Gen , Nanopartículas/química , Células Vegetales/metabolismo , Polietileneimina/química , Dióxido de Silicio/química , Sonicación/métodos , Porosidad
10.
Mater Sci Eng C Mater Biol Appl ; 128: 112316, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34474867

RESUMEN

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.


Asunto(s)
Toxinas Bacterianas , Infecciones por Clostridium , Enteritis , Nanopartículas , Enfermedades de las Aves de Corral , Vacunas , Animales , Anticuerpos Antibacterianos , Embrión de Pollo , Pollos , Infecciones por Clostridium/prevención & control , Infecciones por Clostridium/veterinaria , Enteritis/prevención & control , Enteritis/veterinaria , Enfermedades de las Aves de Corral/prevención & control , Dióxido de Silicio
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