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1.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38673856

RESUMO

Immune response to biomaterials, which is intimately related to their surface properties, can produce chronic inflammation and fibrosis, leading to implant failure. This study investigated the development of magnetic nanoparticles coated with silica and incorporating the anti-inflammatory drug naproxen, aimed at multifunctional biomedical applications. The synthesized nanoparticles were characterized using various techniques that confirmed the presence of magnetite and the formation of a silica-rich bioactive glass (BG) layer. In vitro studies demonstrated that the nanoparticles exhibited bioactive properties, forming an apatite surface layer when immersed in simulated body fluid, and biocompatibility with bone cells, with good viability and alkaline phosphatase activity. Naproxen, either free or encapsulated, reduced nitric oxide production, an inflammatory marker, while the BG coating alone did not show anti-inflammatory effects in this study. Overall, the magnetic nanoparticles coated with BG and naproxen showed promise for biomedical applications, especially anti-inflammatory activity in macrophages and in the bone field, due to their biocompatibility, bioactivity, and osteogenic potential.


Assuntos
Materiais Revestidos Biocompatíveis , Vidro , Nanopartículas de Magnetita , Naproxeno , Naproxeno/farmacologia , Naproxeno/química , Vidro/química , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Nanopartículas de Magnetita/química , Animais , Camundongos , Humanos , Óxido Nítrico/metabolismo , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Dióxido de Silício/química , Sobrevivência Celular/efeitos dos fármacos , Células RAW 264.7 , Osteogênese/efeitos dos fármacos
2.
Int J Mol Sci ; 25(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38203662

RESUMO

Cancer is one of the deadliest diseases worldwide and has been responsible for millions of deaths. However, developing a satisfactory smart multifunctional material combining different strategies to kill cancer cells poses a challenge. This work aims at filling this gap by developing a composite material for cancer treatment through hyperthermia and drug release. With this purpose, magnetic nanoparticles were coated with a polymer matrix consisting of poly (L-co-D,L lactic acid-co-trimethylene carbonate) and a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer. High-resolution transmission electron microscopy and selected area electron diffraction confirmed magnetite to be the only iron oxide in the sample. Cytotoxicity and heat release assays on the hybrid nanoparticles were performed here for the first time. The heat induction results indicate that these new magnetic hybrid nanoparticles are capable of increasing the temperature by more than 5 °C, the minimal temperature rise required for being effectively used in hyperthermia treatments. The biocompatibility assays conducted under different concentrations, in the presence and in the absence of an external alternating current magnetic field, did not reveal any cytotoxicity. Therefore, the overall results indicate that the investigated hybrid nanoparticles have a great potential to be used as carrier systems for cancer treatment by hyperthermia.


Assuntos
Calefação , Hipertermia Induzida , Humanos , Hipertermia , Eletricidade
3.
AAPS PharmSciTech ; 19(3): 1287-1296, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29318467

RESUMO

Several authors have studied the release profile of drugs incorporated in different devices. However, to the best of our knowledge, although many studies have been done on the release of tetracycline, in these release devices, no study has investigated if the released compound is actually the tetracycline, or, instead, a degraded product. This approach is exploited here. In this work, we analyse the influence of two drying methods on the tetracycline delivery behaviour of synthesised glasses using the sol-gel process. We compare the drying methods results using both theoretical models and practical essays, and analyse the chemical characteristic of the released product in order to verify if it remains tetracycline. Samples were freeze-dried or dried in an oven at 37°C and characterised by several methods such as Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), thermogravimetric analysis (TG), differential thermogravimetric analysis (DTG), differential thermal analyses (DTA) and gas adsorption analysis (BET). The released concentration of tetracycline hydrochloride was studied as a function of time, and it was measured by ultraviolet spectrophotometry in the tetracycline wavelength. The drug delivery profiles were reasonably consistent with a diffusion model analysis. In addition, we observed higher release rates for the freeze-dried compared to those dried in an oven at 37°C. This higher release can be attributed to larger pore size for the freeze-dried sample systems with tetracycline, which promoted more water penetration, improving the drug diffusion. The analysis of the solution obtained in the release tests using high-performance liquid chromatography- mass spectrometry (HPLC-MS) confirmed that tetracycline was being released.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Tetraciclinas/síntese química , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Antibacterianos/farmacocinética , Preparações de Ação Retardada/administração & dosagem , Preparações de Ação Retardada/síntese química , Preparações de Ação Retardada/farmacocinética , Difusão , Composição de Medicamentos/métodos , Liofilização/métodos , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Tetraciclinas/administração & dosagem , Tetraciclinas/farmacocinética
4.
J Microencapsul ; 34(6): 535-544, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28795848

RESUMO

The aim of this work was to study the use of different prebiotic biopolymers in lime essential oil microencapsulation. Whey protein isolate, inulin and oligofructose biopolymers were used. The addition of prebiotic biopolymers reduced emulsion viscosity, although it produced larger droplet sizes (0.31-0.32 µm). Moisture values (2.94-3.13 g/100 g dry solids) and water activity (0.152-0.185) were satisfactory, being within the appropriate range for powdered food quality. Total oil content, limonene retention values and antioxidant activity of the microparticles containing essential oil decreased in the presence of the carbohydrates. The addition of prebiotic biopolymers reduced the microparticle thermal stability. X-ray diffraction confirmed the amorphous characteristic of the microparticles and the interaction of the essential oil with the wall material. The presence of prebiotic biopolymers can be a good alternative for lime essential oil microparticles, mainly using fibre that has a functional food appeal and can improve consumer health.


Assuntos
Compostos de Cálcio/química , Inulina/química , Óleos Voláteis/química , Oligossacarídeos/química , Óxidos/química , Biopolímeros/química , Cicloexenos/química , Emulsões , Limoneno , Tamanho da Partícula , Prebióticos , Terpenos/química , Viscosidade
5.
Clin Immunol ; 169: 121-127, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27392462

RESUMO

Common variable immunodeficiency (CVID) is the most common symptomatic primary antibody deficiency and is associated with recurrent infections and chronic inflammatory diseases. We evaluated the ability of Toll-like receptor (TLR) ligands to induce secretion of chemokines, cytokines and type I interferons by peripheral blood mononuclear cells (PBMCs) from CVID patients. High levels of CXCL10, CCL2, CXCL9, CCL5, CXCL8, and IL-6 were detected in sera of CVID patients compared with healthy controls. Increased chemokine levels were observed in unstimulated PBMCs, but after stimulation with TLR2 and TLR4 agonists, equivalent chemokine and pro-inflammatory cytokine secretion, as in healthy controls, was observed, whereas TLR4 agonist induced a decreased secretion of CCL2 and CXCL8 and increased secretion of TNF. Decreased IFN-α secretion induced by TLR7/TLR8 activation was observed in CVID, which was recovered with TLR9 signaling. Our findings revealed that TLR9 activation has an adjuvant effect on the altered type I response in CVID.


Assuntos
Quimiocinas/imunologia , Imunodeficiência de Variável Comum/imunologia , Citocinas/imunologia , Interferon Tipo I/imunologia , Receptores Toll-Like/imunologia , Adulto , Idoso , Células Cultivadas , Quimiocinas/sangue , Quimiocinas/metabolismo , Imunodeficiência de Variável Comum/sangue , Imunodeficiência de Variável Comum/metabolismo , Citocinas/sangue , Citocinas/metabolismo , Feminino , Humanos , Imidazóis/farmacologia , Interferon Tipo I/biossíntese , Interferon Tipo I/sangue , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Ligantes , Lipopolissacarídeos/farmacologia , Masculino , Pessoa de Meia-Idade , Oligodesoxirribonucleotídeos/farmacologia , Poli I-C/farmacologia , Quinolinas/farmacologia , Receptor 4 Toll-Like/agonistas , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismo , Receptor 7 Toll-Like/agonistas , Receptor 7 Toll-Like/imunologia , Receptor 7 Toll-Like/metabolismo , Receptor 8 Toll-Like/agonistas , Receptor 8 Toll-Like/imunologia , Receptor 8 Toll-Like/metabolismo , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/imunologia , Receptor Toll-Like 9/metabolismo , Receptores Toll-Like/agonistas , Receptores Toll-Like/metabolismo , Adulto Jovem
6.
J Transl Med ; 14(1): 171, 2016 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-27286889

RESUMO

BACKGROUND: Lichen planus (LP) is a chronic mucocutaneous inflammatory disease. Evaluating the balance between regulatory T cells and effector T cells could be useful for monitoring the proinflammatory profile of LP. Therefore, this study aimed to assess populations of dendritic cells (DCs) and regulatory and effector T cells in peripheral blood samples collected from patients with LP to evaluate the polyfunctionality of T cells upon toll-like receptor (TLR) activation. METHODS: Peripheral blood mononuclear cells collected from 18 patients with LP and 22 healthy control subjects were stimulated with agonists of TLR4, TLR7, TLR7/TLR8 or TLR9. Frequencies of circulating IFN-α(+) plasmacytoid DCs (pDCs); TNF-α(+) myeloid DCs (mDCs); regulatory T cells (Tregs); and IL-17-, IL-10-, IL-22-, TNF-, and IFN-γ-secreting T cells were assessed via flow cytometry. RESULTS: The frequencies of regulatory CD4(+) and CD8(+)CD25(+)Foxp3(+)CD127(low/-) T cells and TNF-α(+) mDCs were induced following activation with TLR4, TLR7 and TLR8 agonists in the LP group. Moreover, increased baseline frequencies of CD4(+)IL-10(+) T cells and CD8(+)IL-22(+) or IFN-γ(+)T cells were found. In the LP group, TLR4 activation induced an increased frequency of CD4(+)IFN-γ(+) T cells, while TLR7/8 and staphylococcal enterotoxin B (SEB) activation induced an increased frequency of CD8(+) IL-22(+) T cells. An increased frequency of polyfunctional CD4(+) T cells that simultaneously secreted 3 of the evaluated cytokines (not including IL-10) was verified upon TLR7/8/9 activation, while polyfunctional CD8(+) T cells were already detectable at baseline. CONCLUSIONS: TLR-mediated activation of the innate immune response induced the production of proinflammatory mDCs, Tregs and polyfunctional T cells in patients with LP. Therefore, TLR activation has an adjuvant role in inducing both innate and adaptive immune responses.


Assuntos
Células Dendríticas/imunologia , Líquen Plano/imunologia , Células Mieloides/imunologia , Linfócitos T Reguladores/imunologia , Adulto , Idoso , Linfócitos T CD8-Positivos/imunologia , Citocinas/metabolismo , Feminino , Humanos , Líquen Plano/sangue , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Receptores Toll-Like , Fator de Necrose Tumoral alfa/metabolismo , Adulto Jovem
7.
Nanotechnology ; 27(8): 085105, 2016 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-26820520

RESUMO

The combination of magnetic hyperthermia therapy with the controlled release of chemotherapeutic agents in tumors may be an efficient therapeutic with few side effects because the bioavailability, tolerance and amount of the drug can be optimized. Here, we prepared magnetoliposomes consisting of magnetite nanoparticle cores and the anticancer drug gemcitabine encapsulated by a phospholipid bilayer. The potential of these magnetoliposomes for controlled drug release and cancer treatment via hyperthermic behavior was investigated. The magnetic nanoparticle encapsulation efficiency was dependent on the initial amount of magnetite nanoparticles present at the encapsulation stage; the best formulation was 66%. We chose this formulation to characterize the physicochemical properties of the magnetoliposomes and to encapsulate gemcitabine. The mean particle size and distribution were determined by dynamic light scattering (DLS), and the zeta potential was measured. The magnetoliposome formulations all had acceptable characteristics for systemic administration, with a mean size of approximately 150 nm and a polydispersity index <0.2. The magnetoliposomes were stable in aqueous suspension for at least one week, as determined by DLS. Temperature increases due to the dissipation energy of magnetoliposome suspensions subjected to an applied alternating magnetic field (AMF) were measured at different magnetic field intensities, and the values were appropriated for cancer treatments. The drug release profile at 37 °C showed that 17% of the gemcitabine was released after 72 h. Drug release from magnetoliposomes exposed to an AMF for 5 min reached 70%.


Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Preparações de Ação Retardada/química , Desoxicitidina/análogos & derivados , Lipossomos/química , Nanopartículas de Magnetita/química , Animais , Antimetabólitos Antineoplásicos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Preparações de Ação Retardada/farmacologia , Desoxicitidina/metabolismo , Desoxicitidina/farmacologia , Composição de Medicamentos , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Óxido Ferroso-Férrico/química , Hipertermia Induzida/métodos , Luz , Lipossomos/farmacologia , Campos Magnéticos , Nanopartículas de Magnetita/ultraestrutura , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Tamanho da Partícula , Fotoquimioterapia/métodos , Cultura Primária de Células , Ratos , Ratos Endogâmicos Lew , Gencitabina
8.
Acta Derm Venereol ; 96(4): 485-9, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26632637

RESUMO

Lichen planus (LP) is a chronic inflammatory mucocutaneous disease. The inflammatory status of LP may be related to S100A8 (myeloid-related protein 8; MRP8) activation of cytotoxic cells. The aims of this study were to evaluate S100A8 expression in skin lesions and the in vitro effects of S100A8 on CD8+ T cells and natural killer (NK) cells in LP. Increased levels of S100A8/S100A9 were detected in the skin lesions as well as in the sera of subjects with LP. S100A8 expression induced an increased cytotoxic response by peripheral blood CD8+CD107a+ T cells as well as by NK CD56bright cells in patients with LP. Increased expression of interleukin (IL)-1ß, tumour necrosis factor (TNF) and IL-6 in the CD8+ T cells of patients with LP was induced by S100A8, in contrast to the control group that produced IL- 10 and interferon (IFN) type I genes. These data suggest that, in individuals with LP, S100A8 may exert distinct immunomodulatory and cytotoxicity functions.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Calgranulina A/metabolismo , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Líquen Plano/metabolismo , Pele/metabolismo , Antígeno CD56/imunologia , Antígeno CD56/metabolismo , Linfócitos T CD8-Positivos/imunologia , Calgranulina A/imunologia , Calgranulina B/imunologia , Calgranulina B/metabolismo , Estudos de Casos e Controles , Células Cultivadas , Citocinas/genética , Citocinas/imunologia , Humanos , Mediadores da Inflamação/imunologia , Células Matadoras Naturais/imunologia , Células Matadoras Naturais/metabolismo , Líquen Plano/genética , Líquen Plano/imunologia , Líquen Plano/patologia , Proteína 1 de Membrana Associada ao Lisossomo/imunologia , Proteína 1 de Membrana Associada ao Lisossomo/metabolismo , Transdução de Sinais , Pele/imunologia , Pele/patologia , Receptor 4 Toll-Like/imunologia , Receptor 4 Toll-Like/metabolismo , Regulação para Cima
9.
J Nanobiotechnology ; 10: 13, 2012 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-22439913

RESUMO

BACKGROUND: Dengue is a major public health problem worldwide, especially in the tropical and subtropical regions of the world. Infection with a single Dengue virus (DENV) serotype causes a mild, self-limiting febrile illness called dengue fever. However, a subset of patients experiencing secondary infection with a different serotype progresses to the severe form of the disease, dengue hemorrhagic fever/dengue shock syndrome. Currently, there are no licensed vaccines or antiviral drugs to prevent or treat dengue infections. Biodegradable nanoparticles coated with proteins represent a promising method for in vivo delivery of vaccines. FINDINGS: Here, we used a murine model to evaluate the IgG production after administration of inactivated DENV corresponding to all four serotypes adsorbed to bovine serum albumin nanoparticles. This formulation induced a production of anti-DENV IgG antibodies (p < 0.001). However, plaque reduction neutralization assays with the four DENV serotypes revealed that these antibodies have no neutralizing activity in the dilutions tested. CONCLUSIONS: Our results show that while the nanoparticle system induces humoral responses against DENV, further investigation with different DENV antigens will be required to improve immunogenicity, epitope specicity, and functional activity to make this platform a viable option for DENV vaccines.


Assuntos
Anticorpos Antivirais/biossíntese , Vírus da Dengue/imunologia , Nanopartículas , Animais , Vírus da Dengue/crescimento & desenvolvimento , Camundongos , Microscopia Eletrônica de Varredura , Testes de Neutralização , Ensaio de Placa Viral
10.
Sci Rep ; 12(1): 13425, 2022 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-35927566

RESUMO

Although Bioactive Glasses (BGs) have been progressively optimized, their preparation often still involves the use of toxic reagents and high calcination temperatures to remove organic solvents. In the present work, these synthesis related drawbacks were overcome by treating the ashes from the Equisetum hyemale plant in an ethanol/water solution to develop a bioactive composite [glass/carbon (BG-Carb)]. The BG-Carb was characterized by scanning electron microscopy, and transmission electron microscopy; and its chemical composition was assessed by inductively coupled plasma-optical emission spectroscopy. Brunauer-Emmett-Teller gas adsorption analysis showed a specific surface area of 121 m2 g-1. The formation of hydroxyapatite (HA) surface layer in vitro was confirmed by Fourier-transform infrared spectroscopy analysis before and after immersion in simulated body fluid (SBF) solution. The Rietveld refinement of the XRD patterns and selected area electron diffraction analyses confirmed HA in the sample even before immersing it in SBF solution. However, stronger evidences of the presence of HA were observed after immersion in SBF solution due to the surface mineralization. The BG-Carb samples showed no cytotoxicity on MC3T3-E1 cells and osteo-differentiation capacity similar to the positive control. Altogether, the BG-Carb material data reveals a promising plant waste-based candidate for hard and soft tissue engineering.


Assuntos
Materiais Biocompatíveis , Equisetum , Materiais Biocompatíveis/química , Durapatita/química , Vidro/química , Microscopia Eletrônica de Varredura , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual/métodos , Difração de Raios X
11.
Fish Shellfish Immunol Rep ; 2: 100007, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36420484

RESUMO

The host immune system tends to reject xenogenic-implanted cells making tumor development in adult host animal models difficult. Immune system suppression is used for successful xenotransplantation of human cancer cells in many animal models. The studies of cancer development processes in vivo offer opportunities to understand cancer biology and discover new therapeutic strategies. In this context, zebrafish is a model that has been widely applied in the study of human diseases, such as cancer. However, the long-term immunosuppression of these adult zebrafish is still under study as a xenograft animal model for human cancer. This work aimed to evaluate the effects of 21 days of (long-term) exposure of dexamethasone in zebrafish-transplanted with MGSO-3 cells, human breast tumor cell line. Our results show that the animals, while kept on dexamethasone treatment, remained with a 50% reduction in the number of peripheral lymphocytes. In vitro data demonstrated that up to 7 days of dexamethasone treatment did not alter the morphology, proliferation, or viability of MGSO-3 cells. The animals that received a prolonged dexamethasone treatment allowed the engraftment of tumor cells in 100% of the zebrafish tested. These animals also showed tumor progression over 21 days. The experimental group that received only previous exposure to dexamethasone had their tumors regressed after 14 days. In conclusion, the prolonged use of dexamethasone in zebrafish showed a potential strategy for in vivo monitoring of xenograft tumor growth for development studies, as well as in anticancer drug discovery.

12.
J Biomater Appl ; 35(3): 405-421, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32571173

RESUMO

Although, the excellent level of success of titanium surfaces is based on the literature, there are some biological challenges such as unfavorable metabolic conditions or regions of poor bone quality where greater surface bioactivity is desired. Seeking better performance, we hypothesized that silica-based coating via sol-gel route with immersion in potassium hydroxide basic solution induces acceleration of bone mineralization. This in vitro experimental study coated titanium surfaces with bioactive glass synthesized by route sol-gel via hydrolysis and condensation of chemical alkoxide precursor, tetraethylorthosilicate (TEOS) and/or deposition of chemical compound potassium hydroxide (KOH) to accelerate bone apposition. The generated surfaces titanium(T), titanium with potassium hydroxide deposition (T + KOH), titanium with bioactive glass deposition synthesized by sol-gel route via tetraethylorthosilicate hydrolysis (TEOS), titanium with bioactive glass deposition synthesized by sol-gel route via tetraethylorthosilicate hydrolysis with potassium hydroxide deposition (TEOS + KOH) were characterized by 3D optical profilometry, scanning electron microscopy (SEM), transmission electron microscopy (TEM), contact angle by the sessile drop method, x-ray excited photoelectron spectroscopy (XPS) and energy dispersive x-ray spectrometer (EDX). The addition of the KOH group on the pure titanium (T) or bioactive glass (TEOS) surfaces generated a tendency for better results for mineralization. Groups covered with bioactive glass (TEOS, TEOS + KOH) tended to outperform even groups with titanium substrate (T, T + KOH). The addition of both, bioactive glass and KOH, in a single pure titanium substrate yielded the best results for the mineralization process.


Assuntos
Materiais Revestidos Biocompatíveis/química , Géis/química , Hidróxidos/química , Compostos de Potássio/química , Dióxido de Silício/química , Titânio/química , Animais , Calcificação Fisiológica , Adesão Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis/metabolismo , Implantação Dentária , Humanos , Camundongos , Osteogênese , Silanos/química , Propriedades de Superfície , Titânio/metabolismo
13.
J Inorg Biochem ; 206: 111017, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32120160

RESUMO

Cancer-Associated Fibroblasts (CAFs) contribute to tumour progression and have received significant attention as a therapeutic target. These cells produce growth factors, cytokines and chemokines, stimulating cancer cell proliferation and inhibiting their apoptosis. Recent advances in drug delivery have demonstrated a significant promise of iron oxide nanoparticles in clinics as theranostic agents, mainly due to their magnetic properties. Here, we designed superparamagnetic iron oxide nanoparticles (SPIONs) to induce apoptosis of human fibroblasts. SPIONs were synthesized via co-precipitation method and coated with sodium citrate (SPION_Cit). We assessed the intracellular uptake of SPIONs by human fibroblast cells, as well as their cytotoxicity and ability to induce thermal effects under the magnetic field. The efficiency and time of nanoparticle internalization were assessed by Prussian Blue staining, flow cytometry and transmission electron microscopy. SPIONs_Cit were detected in the cytoplasm of human fibroblasts 15 min after in vitro exposure, entering into cells mainly via endocytosis. Analyses through Cell Titer Blue assay, AnnexinV-fluorescein isothiocyanate (FITC) and propidium iodide (PI) cellular staining demonstrated that concentrations below 8 × 10-2 mg/mL of SPIONs_Cit did not alter cell viability of human fibroblast. Furthermore, it was also demonstrated that SPIONs_Cit associated with alternating current magnetic field were able to induce hyperthermia and human fibroblast cell death in vitro, mainly through apoptosis (83.5%), activating caspase 8 (extrinsic apoptotic via) after a short exposure period. Collectively these findings suggest that our nanoplatform is biocompatible and can be used for therapeutic purposes in human biological systems, such as inducing apoptosis of CAFs.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Férricos/farmacologia , Fibroblastos/efeitos dos fármacos , Nanopartículas Magnéticas de Óxido de Ferro/administração & dosagem , Fibroblastos Associados a Câncer/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ácido Cítrico/química , Endocitose , Compostos Férricos/química , Citometria de Fluxo , Humanos , Hipertermia Induzida , Nanopartículas Magnéticas de Óxido de Ferro/química , Microscopia Eletrônica de Transmissão , Neoplasias/metabolismo , Neoplasias/patologia
14.
J Nanosci Nanotechnol ; 9(3): 2081-7, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19435085

RESUMO

It is well known that nano-sized materials often present chemical, electronic, magnetic, and mechanical properties that are potentially interesting for many technological applications comparatively to their corresponding bulk properties. This paper describes the main differences in magnetic properties among nanomagnetite powders prepared by three methods: (I) reduction-precipitation of ferric chloride by reaction with Na2SO3; (II) reduction of hematite with coal, and (III) reduction of hematite with hydrogen gas. The obtained materials were characterized by powder X-ray diffraction (XRD), saturation magnetization measurements, and Mössbauer spectroscopy. Saturation magnetization values varied from 60 to 86 J T(-1)kg(-1). XRD and Mössbauer spectroscopy results at 298 K showed the clear effect of the preparation routes on the crystallographic structure and crystallite size of the magnetic species. Magnetite was formed in varying proportions in all samples, with crystallite sizes estimated by Scherrer formula of about 10, 26, and 33 nm for samples prepared by methods (I), (II), and (III), respectively. The Mössbauer spectrum of the sample prepared by method (I) consisted of broad lines and hyperfine field for magnetite lower than that typically reported for the bulk material.

15.
J Tissue Eng Regen Med ; 13(9): 1651-1663, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31218837

RESUMO

Bioactive glass has been proved to have many applications in bioengineering due to its bone regenerative properties. In this work, an innovative, highly resorbable bioactive glass containing 90% SiO2 (BG90) to be used as a bone substitute was developed. The BG90 was synthetized by the sol-gel process with the dry step at room temperature. The biomaterial showed in vitro and in vivo bioactivities even with silica content up to 90%. Moreover, the BG90 presented high porosity and surface area due to its homogenously interconnected porous network. In vitro, it was observed to have high cell viability and marked osteoblastic differentiation of rat bone marrow-derived cells when in contact with BG90 ion extracts. The BG90 transplantation into rat tibia defects was analysed at 1, 2, 3, 4, 7, and 10 weeks post-operatively and compared with the defects of negative (no graft) and positive (autogenous bone graft) controls. After 4 weeks of grafting, the BG90 was totally resorbed and induced higher bone formation than did the positive control. Bone morphogenetic protein 2 (BMP-2) expression at the grafting site peaked at 1 week and decreased similarly after 7 weeks for all groups. Only the BG90 group was still exhibiting BMP-2 expression in the last experimental time. Our data demonstrated that the BG90 could be an attractive candidate to provide useful approaches in hard-tissue bioengineering.


Assuntos
Cerâmica/farmacologia , Dióxido de Silício/farmacologia , Engenharia Tecidual/métodos , Animais , Materiais Biocompatíveis/farmacologia , Células da Medula Óssea/citologia , Células da Medula Óssea/efeitos dos fármacos , Proteína Morfogenética Óssea 2/metabolismo , Remodelação Óssea/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Durapatita/farmacologia , Células Gigantes/citologia , Células Gigantes/efeitos dos fármacos , Inflamação/patologia , Masculino , Osteogênese/efeitos dos fármacos , Porosidade , Ratos Wistar , Tíbia/efeitos dos fármacos , Tíbia/fisiologia
16.
Arch Dermatol Res ; 310(6): 523-528, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29728859

RESUMO

Lichen planus (LP) is a chronic, mucocutaneous inflammatory disease of an unknown aetiology. The disease has been associated with certain viruses, and the factors such as DAMPs (damage-associated molecular patterns) and PAMPs (pathogen-associated molecular patterns) may also contribute to the inflammatory response in LP. HMGB1 (high mobility group box 1 protein) is one of the major DAMPs that induces inflammation and could trigger LP disease. The present study was aimed to examine TLR4, RAGE and HMGB1 production in epidermis or dermis by immunohistochemistry and the respective expression of these targets in the skin lesions of patients with LP. Moreover, we measured HMGB1 serum levels by ELISA. The results showed similar profile of expression by HMGB1 and TLR4, which are decreased at epidermis and up-regulated at dermis of skin lesions of LP patients that was sustained by intense cellular infiltration. RAGE expression was also increased in dermis of LP. Although there is increased RAGE protein levels, a decreased RAGE transcript levels was detected. Similar HMGB1 serum levels were detected in the LP and control groups. This study demonstrates that HMGB1 and TLR4 could contribute to the inflammatory LP process in skin.


Assuntos
Proteína HMGB1/metabolismo , Líquen Plano/patologia , Receptor 4 Toll-Like/metabolismo , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Derme/patologia , Feminino , Proteína HMGB1/sangue , Humanos , Líquen Plano/sangue , Masculino , Pessoa de Meia-Idade , Receptor para Produtos Finais de Glicação Avançada/metabolismo , Regulação para Cima , Adulto Jovem
17.
J Biomed Mater Res B Appl Biomater ; 83(2): 481-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17443669

RESUMO

Bioactive ceramics have interesting properties from the biological standpoint, but their effects on cellular events remain partially unknown. In the current work, we investigated cellular viability, proliferation, and metabolic activity of rat primary osteoblasts in contact with four different samples: type I collagen, bioactive glass-coated collagen (GC), and both samples submitted to immersion for 5 days in a simulated body fluid. The bioactive glass coating was obtained from a sol-gel process. The cell viability, the alkaline phosphate, the collagen secretion, and the nitric oxide production by osteoblast were measured after 72 h of incubation in the presence of the samples. The GC that was immersed for 5 days in a simulated body fluid solution showed an increase in osteoblast viability and proliferation when it was compared with control and the other samples.


Assuntos
Substitutos Ósseos/farmacologia , Materiais Revestidos Biocompatíveis/farmacologia , Colágeno Tipo I/farmacologia , Vidro , Osteoblastos/efeitos dos fármacos , Fosfatase Alcalina/análise , Animais , Substitutos Ósseos/química , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Materiais Revestidos Biocompatíveis/química , Colágeno Tipo I/química , Osteoblastos/enzimologia , Ratos , Ratos Wistar , Propriedades de Superfície
18.
J Biomed Mater Res B Appl Biomater ; 79(1): 122-8, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16615070

RESUMO

Synthetic bioactive materials offer possibilities to repair large tissue defects. It is well known that bioactivity, angiogenesis, and inflammation are key events in implant incorporation. Using glass-coated and glass-free collagen as potential bone graft substitutes, we carried out in vitro bioactivity and an in vivo angiogenesis and inflammation studies. The in vitro study showed bioactivity when the glass-coated samples were left in SBF for 5 days. This was confirmed by FTIR results, which presented P--O vibration bands characteristic of hydroxyapatite close to 1060 cm(-1) and 600 cm(-1). The in vivo response was evaluated following subcutaneous implantation of the biomaterial in the mouse dorsa. Angiogenesis, as determined by hemoglobin content extracted from implants 7 and 14 days after implantation, increased progressively in both glass-coated and glass-free collagen implants. However, vascularization was higher in the glass-coated collagen implants 14 days after implantation (mug Hb per mg wet tissue 6.0 +/- 0.3) compared with the glass-free group (1.6 +/- 0.1). The inflammatory process, determined by the levels of myeloperoxidase and N-acetylglucosaminidase, was similar for both implants. This study shows that glass-coated collagen implants hold osteogenic and angiogenic potential and may be used in clinical conditions requiring improvement of these biological processes.


Assuntos
Materiais Revestidos Biocompatíveis , Colágeno , Vidro , Transição de Fase , Animais , Inflamação/fisiopatologia , Masculino , Camundongos , Neovascularização Patológica/fisiopatologia
19.
Curr Pharm Des ; 21(37): 5417-33, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26377654

RESUMO

Superparamagnetic iron oxides, as magnetite (Fe3O4) or maghemite (γ-Fe2O3), are primary materials with intrinsic properties that enable them, as single components or as special composites, to base advanced techniques in medical clinical practices, as a contrast agent in magnetic resonance imaging (MRI), as magnetically-induced hyperthermic heat generator, and as a magnetic guide to locally deliver drugs to specific sites in the human body. An interesting approach to developing nanoplatforms for those applications consists in manufacturing core@shell nanostructures, in which the precursor magnetic iron oxide (usually, magnetite) acts as a core, and an organic, or inorganic compound is used as a shell in a multifunctional composite. In this review, we report the current advances in the use of magnetite-based core@shell nanostructures, including Fe3O4@SiO2 and Fe3O4@polymers, in MRI, magnetic hyperthermia and drug delivery systems for diagnosis and therapy of tumor cells. The development of nanoplatforms for combined therapy and diagnostic (theranostic) is also addressed.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Nanopartículas de Magnetita/química , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Compostos Férricos/administração & dosagem , Compostos Férricos/química , Óxido Ferroso-Férrico/administração & dosagem , Óxido Ferroso-Férrico/química , Humanos , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita/administração & dosagem , Tamanho da Partícula
20.
Arch Dermatol Res ; 307(3): 259-64, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25384438

RESUMO

Lichen planus (LP) is a common inflammatory skin disease of unknown etiology. Reports of a common transactivation of quiescent human endogenous retroviruses (HERVs) support the connection of viruses to the disease. HERVs are ancient retroviral sequences in the human genome and their transcription is often deregulated in cancer and autoimmune diseases. We explored the transcriptional activity of HERV sequences as well as the antiviral restriction factor and interferon-inducible genes in the skin from LP patients and healthy control (HC) donors. The study included 13 skin biopsies from patients with LP and 12 controls. Real-time PCR assay identified significant decrease in the HERV-K gag and env mRNA expression levels in LP subjects, when compared to control group. The expressions of HERV-K18 and HERV-W env were also inhibited in the skin of LP patients. We observed a strong correlation between HERV-K gag with other HERV sequences, regardless the down-modulation of transcripts levels in LP group. In contrast, a significant up-regulation of the cytidine deaminase APOBEC 3G (apolipoprotein B mRNA-editing), and the GTPase MxA (Myxovirus resistance A) mRNA expression level was identified in the LP skin specimens. Other transcript expressions, such as the master regulator of type I interferon-dependent immune responses, STING (stimulator of interferon genes) and IRF-7 (interferon regulatory factor 7), IFN-ß and the inflammassome NALP3, had increased levels in LP, when compared to HC group. Our study suggests that interferon-inducible factors, in addition to their role in innate immunity against exogenous pathogens, contribute to the immune control of HERVs. Evaluation of the balance between HERV and interferon-inducible factor expression could possibly contribute to surveillance of inflammatory/malignant status of skin diseases.


Assuntos
Retrovirus Endógenos/metabolismo , Produtos do Gene env/metabolismo , Produtos do Gene gag/metabolismo , Interferon beta/metabolismo , Líquen Plano/imunologia , Proteínas de Membrana/metabolismo , Proteínas da Gravidez/metabolismo , Pele/metabolismo , Superantígenos/metabolismo , Desaminase APOBEC-3G , Adulto , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Citidina Desaminase/genética , Citidina Desaminase/metabolismo , Retrovirus Endógenos/genética , Feminino , Regulação Viral da Expressão Gênica , Produtos do Gene env/genética , Produtos do Gene gag/genética , Humanos , Vigilância Imunológica , Fator Regulador 7 de Interferon/genética , Fator Regulador 7 de Interferon/metabolismo , Interferon beta/genética , Líquen Plano/genética , Líquen Plano/virologia , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Proteínas de Resistência a Myxovirus/genética , Proteínas de Resistência a Myxovirus/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR , Proteínas da Gravidez/genética , Pele/virologia , Superantígenos/genética , Ativação Transcricional , Regulação para Cima , Adulto Jovem
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