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1.
Nanomaterials (Basel) ; 8(12)2018 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-30563227

RESUMO

Magnetic nanoparticles (MNPs) of magnetite (Fe3O4) were prepared using a polystyrene-graft-poly(2-vinylpyridine) copolymer (denoted G0PS-g-P2VP or G1) as template. These MNPs were subjected to self-assembly with a poly(acrylic acid)-block-poly(2-hydroxyethyl acrylate) double-hydrophilic block copolymer (DHBC), PAA-b-PHEA, to form water-dispersible magnetic polyion complex (MPIC) micelles. Large Fe3O4 crystallites were visualized by transmission electron microscopy (TEM) and magnetic suspensions of MPIC micelles exhibited improved colloidal stability in aqueous environments over a wide pH and ionic strength range. Biological cells incubated for 48 h with MPIC micelles at the highest concentration (1250 µg of Fe3O4 per mL) had a cell viability of 91%, as compared with 51% when incubated with bare (unprotected) MNPs. Cell internalization, visualized by confocal laser scanning microscopy (CLSM) and TEM, exhibited strong dependence on the MPIC micelle concentration and incubation time, as also evidenced by fluorescence-activated cell sorting (FACS). The usefulness of MPIC micelles for cellular radiofrequency magnetic field hyperthermia (MFH) was also confirmed, as the MPIC micelles showed a dual dose-dependent effect (concentration and duration of magnetic field exposure) on the viability of L929 mouse fibroblasts and U87 human glioblastoma epithelial cells.

2.
Adv Healthc Mater ; 7(11): e1701059, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29577666

RESUMO

Bioconjugation of enzymes on coatings based on polydopamine (PDA) layers is an appealing approach to control biological responses on biomedical implant surfaces. As alternative to PDA wet deposition, a fast, solvent-free, and dynamic deposition approach based on atmospheric-pressure plasma dielectric barrier discharge process is considered to deposit on metallic surfaces acrylic-based interlayers containing highly chemically reactive catechol/quinone groups. A biomimetic approach based on covalent immobilization of Dispersin B, an enzyme with antibiofilm properties, shows the bioconjugation potential of the novel plasma polymer layers. The excellent antibiofilm activity against Staphylococcus epidermidis is comparable to the PDA-based layers prepared by wet chemical methods with slow deposition rates. A study of preosteoblastic MG-63 human cell line viability and adhesion properties on plasma polymer layers demonstrates early interaction required for biomedical applications.


Assuntos
Benzoquinonas , Biofilmes/efeitos dos fármacos , Catecóis , Indóis , Metacrilatos , Gases em Plasma/química , Polímeros , Animais , Benzoquinonas/química , Benzoquinonas/farmacologia , Biofilmes/crescimento & desenvolvimento , Catecóis/química , Catecóis/farmacologia , Linhagem Celular , Indóis/química , Indóis/farmacologia , Teste de Materiais , Metacrilatos/química , Metacrilatos/farmacologia , Camundongos , Polímeros/química , Polímeros/farmacologia , Staphylococcus epidermidis/fisiologia
3.
Clin Proteomics ; 14: 9, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28344541

RESUMO

BACKGROUND: Despite recent advances in colorectal cancer (CRC) diagnosis and population screening programs, the identification of patients with preneoplastic lesions or with early CRC stages remains challenging and is important for reducing CRC incidence and increasing patient's survival. METHODS: We analysed 76 colorectal tissue samples originated from early CRC stages, normal or inflamed mucosa by label-free proteomics. The characterisation of three selected biomarker candidates was performed by immunohistochemistry on an independent set of precancerous and cancerous lesions harbouring increasing CRC stages. RESULTS: Out of 5258 proteins identified, we obtained 561 proteins with a significant differential distribution among groups of patients and controls. KNG1, OLFM4 and Sec24C distributions were validated in tissues and showed different expression levels especially in the two early CRC stages compared to normal and preneoplastic tissues. CONCLUSION: We highlighted three proteins that require further investigations to better characterise their role in early CRC carcinogenesis and their potential as early CRC markers.

4.
Macromol Biosci ; 17(7)2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28297161

RESUMO

Polydimethylsiloxane (PDMS) constitutes an interesting material for a variety of biomedical applications, especially as intraocular lenses (IOLs), for its excellent transparency. In this work, a photoreversible PDMS-coumarin network, whose shape and properties can be adjusted postoperatively in a noninvasive manner, is developed. The synthesis of PDMS-coumarin is achieved by amidation of a coumarin acid chloride derivative with amine-functionalized PDMSs. Under exposure of λ > 300 nm, these polymers can be cured by dimerization of coumarin. The cured polymers can be uncrosslinked via photocleavage of cyclobutane dimers upon illumination at λ < 290 nm. The diffusion of linear PDMSs in a crosslinked network and the controlled shape modification are studied, which demonstrate that these polymers are good candidates for adjustable IOL application. IOL disks prepared from these materials show high hydrophobicity and good transparency. In vitro cytotoxicity, lens epithelial cell adhesion assays, and rabbit host reaction against implanted disks demonstrate the biocompatibility of the polymer.


Assuntos
Cumarínicos/química , Fibroblastos/metabolismo , Lentes Intraoculares , Teste de Materiais , Silicones/química , Animais , Linhagem Celular , Camundongos
5.
Dent Mater ; 33(3): 333-343, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28159322

RESUMO

OBJECTIVE: Biocompatibility of polymer-infiltrated-ceramic-network (PICN) materials, a new class of CAD-CAM composites, is poorly explored in the literature, in particular, no data are available regarding Human Gingival Keratinocytes (HGK). The first objective of this study was to evaluate the in vitro biocompatibility of PICNs with HGKs in comparison with other materials typically used for implant prostheses. The second objective was to correlate results with PICN monomer release and indirect cytotoxicity. METHODS: HGK attachment, proliferation and spreading on PICN, grade V titanium (Ti), yttrium zirconia (Zi), lithium disilicate glass-ceramic (eM) and polytetrafluoroethylene (negative control) discs were evaluated using a specific insert-based culture system. For PICN and eM samples, monomer release in the culture medium was quantified by high performance liquid chromatography and indirect cytotoxicity tests were performed. RESULTS: Ti and Zi exhibited the best results regarding HGK viability, number and coverage. eM showed inferior results while PICN showed statistically similar results to eM but also to Ti regarding cell number and to Ti and Zi regarding cell viability. No monomer release from PICN discs was found, nor indirect cytotoxicity, as for eM. SIGNIFICANCE: The results confirmed the excellent behavior of Ti and Zi with gingival cells. Even if polymer based, PICN materials exhibited intermediate results between Ti-Zi and eM. These promising results could notably be explained by PICN high temperature-high pressure (HT-HP) innovative polymerization mode, as confirmed by the absence of monomer release and indirect cytotoxicity.


Assuntos
Cerâmica , Porcelana Dentária , Queratinócitos , Polímeros , Desenho Assistido por Computador , Gengiva , Humanos , Teste de Materiais , Zircônio
6.
Langmuir ; 32(50): 13482-13492, 2016 12 20.
Artigo em Inglês | MEDLINE | ID: mdl-27993030

RESUMO

Water-dispersible polyion complex (PIC) micelles were prepared by the self-assembly of an arborescent polystyrene-graft-poly(2-vinylpyridine) copolymer (denoted G0PS-g-P2VP or G1) serving as core and a poly(acrylic acid)-block-poly(2-hydroxyethyl acrylate) (PAA-b-PHEA) double-hydrophilic block copolymer (DHBC) forming a shell. Varying the density of hydrophilic polymer chains in the stabilizing layer provided control over the size and structure of the entities obtained, from large flocculated species to stable isolated PIC micelles with diameters ranging from 42 to 67 nm. The hydrodynamic radius (determined from dynamic light scattering measurements), and the weight-average molar mass (M̅w) and radius of gyration of the scatterers (extracted from static multiangle light scattering data) evidenced the formation of either isolated or aggregated PIC micelles depending on the self-assembly conditions used (pH, concentration and mixing molar ratio f). Changes in the morphology of the arborescent copolymer after complexation were observed by atomic force microscopy (AFM) imaging. In particular, by varying the force applied with the AFM tip on the samples, the core-shell structure of the PIC micelles was clearly evidenced. The PIC micelles displayed no significant cytotoxicity toward mouse fibroblast L929 cells, a standard cell line recommended for toxicity assays, due to the good biocompatibility of the hydrophilic PAA-b-PHEA shell. In spite of a negative residual zeta potential due to an excess of negative charges, fluorescently labeled PIC* micelles were successfully internalized by L929 cells, as confirmed by laser scanning confocal microscopy (LSCM) and transmission electron microscopy (TEM).

7.
Dent Mater ; 32(9): 1152-64, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27402299

RESUMO

OBJECTIVES: Polymer-infiltrated-ceramic-network (PICN) materials constitute an innovative class of CAD-CAM materials offering promising perspectives in prosthodontics, but no data are available in the literature regarding their biological properties. The objective of the present study was to evaluate the in vitro biocompatibility of PICNs with human gingival fibroblasts (HGFs) in comparison with materials typically used for implant prostheses and abutments. METHODS: HGF attachment, proliferation and spreading on discs made of PICN, grade V titanium (Ti), yttrium zirconia (Zi), lithium disilicate glass-ceramic (eM) and polytetrafluoroethylene (negative control), were evaluated using a specific insert-based culture system (IBS-R). Sample surface properties were characterized by XPS, contact angle measurement, profilometry and SEM. RESULTS: Ti and Zi gave the best results regarding HGF viability, morphology, number and coverage increase with time in comparison with the negative control, while PICN and eM gave intermediate results, cell spreading being comparable for PICN, Ti, Zi and eM. Despite the presence of polymers and their related hydrophobicity, PICN exhibited comparable results to glass-ceramic materials, which could be explained by the mode of polymerization of the monomers. SIGNIFICANCE: The results of the present study confirm that the currently employed materials, i.e. Ti and Zi, can be considered to be the gold standard of materials in terms of HGF behavior, while PICN gave intermediate results comparable to eM. The impact of the present in vitro results needs to be further investigated clinically, particularly in the view of the utilization of PICNs for prostheses on bone-level implants.


Assuntos
Cerâmica , Desenho Assistido por Computador , Porcelana Dentária , Gengiva/citologia , Polímeros , Fibroblastos , Humanos , Teste de Materiais , Propriedades de Superfície , Zircônio
8.
Mar Pollut Bull ; 108(1-2): 70-6, 2016 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-27197766

RESUMO

Previous studies described high concentrations of mercury (Hg) and selenium (Se) in the blood of harbour seals, Phoca vitulina from the North Sea. In the present study, we evaluated the in vitro potential protective effects of sodium selenite (Na2SeO3) and selenomethionine (SeMet) on cell proliferation of harbour seal lymphocytes exposed to MeHgCl 0.75µM. In vitro exposure of ConA-stimulated T lymphocytes resulted in severe inhibition of DNA synthesis, likely linked to severe loss of mitochondrial membrane potential at 0.75µM. Neither selenite nor SeMet showed a protective effect against MeHg toxicity expressed at the T lymphocyte proliferation level for harbour seals. Selenite and SeMet did not show negative effects regarding lymphocyte proliferation and mitochondrial membrane potential. To conclude, our results clearly demonstrated that MeHg affected in vitro immune cells exposure with no protective effects of selenium at a molar ratio Hg:Se of 1:10 in harbour seals from the North Sea.


Assuntos
Leucócitos/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Phoca , Selênio/química , Poluentes Químicos da Água/toxicidade , Animais , Proliferação de Células , Células Cultivadas , Potencial da Membrana Mitocondrial , Mercúrio/toxicidade
9.
Cytotechnology ; 68(6): 2437-2448, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27015830

RESUMO

In vitro studies about biomaterials biological properties are essential screening tests. Yet cell cultures encounter difficulties related to cell retention on material surface or to the observation of both faces of permeable materials. The objective of the present study was to develop a reliable in vitro method to study cell behavior on rigid and flexible/permeable biomaterials elaborating two specific insert-based systems (IBS-R and IBS-F respectively). IBS-R was designed as a specific cylindrical polytetrafluoroethylene (PTFE) system to evaluate attachment, proliferation and morphology of human gingival fibroblasts (HGFs) on grade V titanium and lithium disilicate glass-ceramic discs characteristics of dental prostheses. The number of cells, their covering on discs and their morphology were determined from MTS assays and microscopic fluorescent images after 24, 48 and 72 h. IBS-F was developed as a two components system to study HGFs behavior on guided bone regeneration polyester membranes. The viability and the membrane barrier effect were evaluated by metabolic MTS assays and by scanning electron microscopy. IBS-R and IBS-F were shown to promote (1) easy and rapid handling; (2) cell retention on biomaterial surface; (3) accurate evaluation of the cellular proliferation, spreading and viability; (4) use of non-toxic material. Moreover IBS-F allowed the study of the cell migration through degradable membranes, with an access to both faces of the biomaterial and to the bottom of culture wells for medium changing.

10.
Arch Environ Contam Toxicol ; 70(1): 133-42, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26264045

RESUMO

Methylmercury (MeHg) is highly immunotoxic and can alter the health status of the harbour seal, Phoca vitulina, from the North Sea. To investigate the mechanism of MeHg-induced toxicity in harbour seal lymphocytes, Concanavalin A (ConA)-stimulated peripheral blood leucocytes were exposed in vitro to sublethal concentrations of MeHgCl (0.2, 1, and 2 µM) for 72 h and then analysed for their viability and ultrastructure. After 72 h of incubation, cells were counted with a propidium iodide staining technique, a metabolic MTS assay was performed, and cells exposed to 1 µM of MeHgCl were observed by transmission electron microscopy (TEM). Alive cell numbers decreased with increased MeHgCl concentrations. In presence of ConA and 1 µM of MeHgCl, TEM images revealed a higher frequency of apoptotic cells. Exposed cells displayed condensation of the chromatin at the nuclear membrane and mitochondrial damages. The results suggest that in vitro MeHgCl-induced apoptosis in harbour seal lymphocytes through a mitochondrial pathway.


Assuntos
Linfócitos/efeitos dos fármacos , Compostos de Metilmercúrio/toxicidade , Phoca , Poluentes Químicos da Água/toxicidade , Animais , Técnicas In Vitro , Microscopia Eletrônica
11.
Soft Matter ; 11(17): 3354-9, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25793873

RESUMO

The solution behaviour in water of a polyoxazoline-type block copolymer, namely poly(2-isopropyl-2-oxazoline)-block-poly(2-methyl-2-oxazoline), denoted as P(iPrOx-b-MeOx), above the lower critical solution temperature (LCST) of the PiPrOx block was exploited to induce a temporary or permanent self-assembly. Spherical micelles were first obtained and could be disassembled in a reversible manner when kept for a short period of time (i.e. t < 90 min) above the LCST, and cooled down to room temperature. In contrast, annealing the copolymer solution for more than 90 min at 65 °C induced the crystallisation of the PiPrOx block, as evidenced by wide angle X-ray scattering (WAXS) experiments. This crystallisation-driven self-assembly phenomenon resulted in different morphologies, including spherical and distorted crystallised micelles and micron-size fibers, their relative proportion varies with the annealing time. Formation of micron-size range fiber-like structures might be explained by the re-organization of parent crystallised micelles. The crystal structure, as determined by WAXS, appeared to be identical to that of the PiPrOx homopolymer.

12.
Small ; 11(19): 2323-32, 2015 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-25580816

RESUMO

In this study, we report the synthesis of a nanoscaled drug delivery system, which is composed of a gold nanorod-like core and a mesoporous silica shell (GNR@MSNP) and partially uploaded with phase-changing molecules (1-tetradecanol, TD, T(m) 39 °C) as gatekeepers, as well as its ability to regulate the release of doxorubicin (DOX). Indeed, a nearly zero premature release is evidenced at physiological temperature (37 °C), whereas the DOX release is efficiently achieved at higher temperature not only upon external heating, but also via internal heating generated by the GNR core under near infrared irradiation. When tagged with folate moieties, GNR@MSNPs target specifically to KB cells, which are known to overexpress the folate receptors. Such a precise control over drug release, combining with the photothermal effect of GNR cores, provides promising opportunity for localized synergistic photothermal ablation and chemotherapy. Moreover, the performance in killing the targeted cancer cells is more efficient compared with the single phototherapeutic modality of GNR@MSNPs. This versatile combination of local heating, phototherapeutics, chemotherapeutics and gating components opens up the possibilities for designing multifunctional drug delivery systems.


Assuntos
Sistemas de Liberação de Medicamentos/métodos , Liberação Controlada de Fármacos , Ouro/química , Raios Infravermelhos , Nanotubos/química , Fototerapia/métodos , Dióxido de Silício/química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Ácido Fólico/farmacologia , Temperatura Alta , Humanos , Microscopia de Fluorescência , Nanotubos/ultraestrutura , Porosidade
13.
Biomacromolecules ; 16(1): 183-91, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-25409266

RESUMO

Hydrophilic nanogels based on partially hydrolyzed poly(2-ethyl-2-oxazoline) were synthesized in dilute aqueous media in the presence of 1,6-hexanediol diglycidyl ether as a cross-linker. Nanogel formation was monitored by DLS and HSQC NMR spectroscopy, and the final nano-objects were characterized by DLS, TEM, AFM, and NanoSight analyses. Nanogels with a hydrodynamic radius of 78 nm exhibiting a slight positive surface charge were obtained. MTS assays (cell metabolic activity test) evidenced that nanogels were nontoxic in the investigated concentration range (i.e., 0.1 to 400 µg/mL) and that no specific interaction with bovine serum albumin was observed.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas/química , Oxazóis/química , Polietilenoglicóis/química , Polietilenoimina/química , Animais , Materiais Biocompatíveis/metabolismo , Bovinos , Linhagem Celular , Camundongos , Nanogéis , Nanopartículas/metabolismo , Oxazóis/metabolismo , Polietilenoglicóis/metabolismo , Polietilenoimina/metabolismo , Soroalbumina Bovina/metabolismo
14.
J Biomed Mater Res B Appl Biomater ; 103(6): 1274-86, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25352276

RESUMO

Ophthalmic lenses are medical devices with considerable requirements in terms of optical, biomechanical and biological performance. There is limited number of materials used for their manufacturing, comprising mainly silicones and poly(meth)acrylates. This series of publications aims at investigating the applicability of thermoplastic polyurethane elastomers (TPU) for the manufacturing of ophthalmic lenses and examining the properties of the respective devices. This study is related to the synthesis of TPUs with chemical compositions that comprise chemically grafted filters for the hazardous-light. GC-MS, attenuated total reflectance Fourier transform infrared spectroscopy, and UV-vis spectroscopies confirmed the reaction completion and the beneficial effect of the filters on the light transmittance, respectively. Relatively high refractive index of the material was measured and allows for the manufacturing of thinner lenses. The contrast sensitivity determined for a model intraocular lens (IOL) was satisfactory. Few optical defects were, however, present on the model lens prepared by thermoplastic injection molding. The elasticity of the materials was evaluated in view to their potential applicability as foldable IOLs by determining their glass transition temperature and their Young modulus and measuring their shore A. The TPU materials demonstrated more bioadhesive character compared with a benchmark hydrophilic acrylic reference material, which is already used for IOL manufacturing.


Assuntos
Células Epiteliais/metabolismo , Lentes Intraoculares , Teste de Materiais , Poliuretanos/química , Animais , Adesão Celular , Células Cultivadas , Células Epiteliais/citologia , Humanos , Suínos
15.
J Proteomics ; 112: 250-61, 2015 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-25218866

RESUMO

Formalin-fixed paraffin-embedded (FFPE) specimens of patients are useful sources of materials for clinical research and have recently gained interest for use in the discovery of clinical proteomic biomarkers. However, the critical step in this field is the ability to obtain an efficient and repeatable extraction using the limited quantities of material available for research in hospital biobanks. This work describes the evaluation of the peptide/protein extraction using FFPE sections treated by the following two methods before shotgun proteomic analysis: a commercial solution (FFPE-FASP) (filter aided sample preparation) and an antigen retrieval-derived protocol (On Slice AR). Their efficiencies and repeatabilities are compared using data-independent differential quantitative label-free analysis. FFPE-FASP was shown to be globally better both qualitatively and quantitatively than On Slice AR. FFPE-FASP was tested on several samples, and differential analysis was used to compare the tissues of diverticulitis patients (healthy and inflammatory tissues). In this differential proteomic analysis using retrospective clinical FFPE material, FFPE-FASP was reproducible and provided a high number of confident protein identifications, highlighting potential protein biomarkers. BIOLOGICAL SIGNIFICANCE: In clinical proteomics, FFPE is an important resource for retrospective analysis and for the discovery of biomarkers. The challenge for FFPE shotgun proteomic analysis is preparation by an efficient and reproducible protocol, which includes protein extraction and digestion. In this study, we analyzed two different methods and evaluated their repeatabilities and efficiencies. We illustrated the reproducibility of the most efficient method, FFPE-FASP, by a pilot study on diverticulitis tissue and on FFPE samples amount accessible in hospital biobanks. These data showed that FFPE is suitable for use in clinical proteomics, especially when the FFPE-FASP method is combined with label-free shotgun proteomics as described in the workflow presented in this work.


Assuntos
Diverticulite/metabolismo , Peptídeos , Proteômica/métodos , Biomarcadores/análise , Biomarcadores/química , Diverticulite/patologia , Feminino , Formaldeído/química , Humanos , Masculino , Inclusão em Parafina , Peptídeos/análise , Peptídeos/química , Peptídeos/isolamento & purificação
16.
PLoS One ; 9(12): e114973, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25501012

RESUMO

Posterior Capsular Opacification (PCO) is the capsule fibrosis developed on implanted IntraOcular Lens (IOL) by the de-differentiation of Lens Epithelial Cells (LECs) undergoing Epithelial Mesenchymal Transition (EMT). Literature has shown that the incidence of PCO is multifactorial including the patient's age or disease, surgical technique, and IOL design and material. Reports comparing hydrophilic and hydrophobic acrylic IOLs have shown that the former has more severe PCO. On the other hand, we have previously demonstrated that the adhesion of LECs is favored on hydrophobic compared to hydrophilic materials. By combining these two facts and contemporary knowledge in PCO development via the EMT pathway, we propose a biomimetically inspired strategy to promote LEC adhesion without de-differentiation to reduce the risk of PCO development. By surface grafting of a cell adhesion molecule (RGD peptide) onto the conventional hydrophilic acrylic IOL material, the surface-functionalized IOL can be used to reconstitute a capsule-LEC-IOL sandwich structure, which has been considered to prevent PCO formation in literature. Our results show that the innovative biomaterial improves LEC adhesion, while also exhibiting similar optical (light transmittance, optical bench) and mechanical (haptic compression force, IOL injection force) properties compared to the starting material. In addition, compared to the hydrophobic IOL material, our bioactive biomaterial exhibits similar abilities in LEC adhesion, morphology maintenance, and EMT biomarker expression, which is the crucial pathway to induce PCO. The in vitro assays suggest that this biomaterial has the potential to reduce the risk factor of PCO development.


Assuntos
Opacificação da Cápsula/patologia , Catarata/terapia , Transição Epitelial-Mesenquimal/efeitos dos fármacos , Lentes Intraoculares/efeitos adversos , Animais , Opacificação da Cápsula/cirurgia , Catarata/patologia , Extração de Catarata/efeitos adversos , Adesão Celular/efeitos dos fármacos , Desdiferenciação Celular/efeitos dos fármacos , Linhagem Celular , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/patologia , Humanos , Próteses e Implantes/efeitos adversos , Suínos
17.
OMICS ; 18(9): 539-52, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25105455

RESUMO

The concept of tissues appeared more than 200 years ago, since textures and attendant differences were described within the whole organism components. Instrumental developments in optics and biochemistry subsequently paved the way to transition from classical to molecular histology in order to decipher the molecular contexts associated with physiological or pathological development or function of a tissue. In 1941, Coons and colleagues performed the first systematic integrated examination of classical histology and biochemistry when his team localized pneumonia antigens in infected tissue sections. Most recently, in the early 21(st) century, mass spectrometry (MS) has progressively become one of the most valuable tools to analyze biomolecular compounds. Currently, sampling methods, biochemical procedures, and MS instrumentations allow scientists to perform "in depth" analysis of the protein content of any type of tissue of interest. This article reviews the salient issues in proteomics analysis of tissues. We first outline technical and analytical considerations for sampling and biochemical processing of tissues and subsequently the instrumental possibilities for proteomics analysis such as shotgun proteomics in an anatomical context. Specific attention concerns formalin fixed and paraffin embedded (FFPE) tissues that are potential "gold mines" for histopathological investigations. In all, the matrix assisted laser desorption/ionization (MALDI) MS imaging, which allows for differential mapping of hundreds of compounds on a tissue section, is currently the most striking evidence of linkage and transition between "classical" and "molecular" histology. Tissue proteomics represents a veritable field of research and investment activity for modern biomarker discovery and development for the next decade.


Assuntos
Histologia/tendências , Proteômica/tendências , Imuno-Histoquímica , Microdissecção e Captura a Laser , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
18.
J Cataract Refract Surg ; 40(9): 1536-44, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25135546

RESUMO

PURPOSE: To compare hydrophilic and hydrophobic acrylic materials designed for intraocular lenses in a multiparametric investigation in a liquid environment to highlight their properties in terms of adhesion forces, lens epithelial cell (LEC) adhesion, and tissue response as indicators of the risk for posterior capsule opacification (PCO) development. SETTING: University of Liège, Liège, Belgium. DESIGN: Experimental study. METHODS: The hydrophobicity and surface adhesion force were assessed using contact-angle and atomic force microscopy measurements. The bioadhesiveness of the disks and the tissue response were determined by in vitro experiments using bovine serum albumin and porcine LECs and by in vivo rabbit subcutaneous implantation, respectively. RESULTS: Increasing surface hydrophobicity led to a greater surface-adhesion force and greater LEC adhesion. After 1 month, the rabbit subcutaneous implants showed a similar thin layer of fibrous capsule surrounding the disks without extensive inflammation. A layer of rounded cells in contact with disks was detected on the hydrophobic samples only. CONCLUSIONS: Hydrophobic acrylic disks that have been associated with a reduced risk for PCO in clinical studies showed increased tackiness. FINANCIAL DISCLOSURES: Proprietary or commercial disclosures are listed after the references.


Assuntos
Resinas Acrílicas , Adesão Celular/fisiologia , Células Epiteliais/fisiologia , Cristalino/citologia , Lentes Intraoculares , Soroalbumina Bovina/metabolismo , Adsorção , Animais , Materiais Biocompatíveis , Células Cultivadas , Interações Hidrofóbicas e Hidrofílicas , Implante de Lente Intraocular , Microscopia de Força Atômica , Ligação Proteica , Coelhos , Tela Subcutânea/cirurgia , Propriedades de Superfície , Suínos , Aderências Teciduais
19.
J Mater Chem B ; 2(1): 59-70, 2014 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-32261299

RESUMO

Core-shell nanoparticles made of a maghemite core and a mesoporous silica shell were developed as drug delivery systems (DDS). Doxorubicin® (DOX, DNA intercalating drug) was loaded within the mesoporous cavities, while phase-change molecules (PCMs), e.g. 1-tetradecanol (TD) with a melting temperature (Tm) of 39 °C, were introduced as gatekeepers to regulate the release behaviours. An overall loading amount of ca. 20 wt% (TD/DOX ca. 50/50 wt/wt) was confirmed. Heat-triggered release of DOX evidenced a "zero premature release" (<3% of the entire payload in 96 h release) under physiological conditions (37 °C), and however, a sustainable release (ca. 40% of the entire payload in 96 h) above Tm of TD (40 °C). It also demonstrated the possibility to deliver drug payloads in small portions (pulsatile release mode) via multiple heating on/off cycles, due to the reversible phase change of the PCMs. In vitro heat-triggered release of DOX within cell culture of the MEL-5 melanoma cell line was also tested. It was found that DOX molecules were trapped efficiently within the mesopores even after internalization within the cytoplasm of MEL-5 cells at 37 °C, with the potential toxicity of DOX strongly quenched (>95% viability after 72 h incubation). However, continuous cell apoptosis was detected at cell culture temperature above Tm of TD, due to the heat-triggered release of DOX (<50% viability after 72 h incubation at 40 °C). Moreover, due to the presence of a maghemite core within the DDS, T2-weighted magnetic resonance imaging performance was also confirmed. These as-designed core-shell nanoparticles are envisaged to become promising DDS for "on-demand" heat-triggered release.

20.
J Mater Chem B ; 2(8): 1009-1023, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32261619

RESUMO

Reversibly crosslinked (RCL) nanogels made of thermo-responsive poly(vinyl alcohol)-b-poly(N-vinylcaprolactam) copolymers were combined with maghemite nanoparticles and developed as new drug delivery systems (DDS). The crosslinking was formed via boronate/diol bonding from the surface-functionalized superparamagnetic maghemite nanoparticles, endowing the DDS with thermo-, pH- and glucose-responsiveness. The capability to load a hydrophobic drug model Nile red (NR) within the RCL nanogels was evaluated, and stimuli-triggered drug release behaviours under different conditions were tested. Zero premature release behaviour was detected at physiological pH in the absence of glucose, whereas triggered release was observed upon exposure to acidic pH (5.0) and/or in the presence of glucose. In light of the superparamagnetic properties of the maghemite nanoparticles and RCL nanogels, magnetically-induced heating, MR imaging performance, as well as remotely magnetically-triggered drug release under alternating magnetic field (AMF), were investigated. Cytotoxicity against fibroblast-like L929 and human melanoma MEL-5 cell lines was assessed via the MTS assay. In vitro stimuli-triggered release of tamoxifen, a chemotherapeutic drug, was also studied within MEL-5 cell cultures under different conditions. These innovative RCL nanogels, integrating different stimuli-responsive components, hydrophobic chemotherapeutic moieties and also diagnostic agents together via reversible crosslinking, are promising new theranostic platforms.

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