122 research outputs found
Magnetoliposomes based on nickel/silica core/shell nanoparticles : synthesis and characterization
"Available online 18 September 2014"In the present work, nickel magnetic nanoparticles with diameters lower than 100nm, with and without silica shell, were synthesized by microheterogeneous templating. The magnetic properties of the nanoparticles show a typical ferromagnetic behavior with a coercive field of 80Oe. Dry magnetoliposomes (DMLs) with diameter between 58nm and 76nm were obtained from the synthesis of nanoparticles in the presence of a lipid or surfactant layer, and aqueous magnetoliposomes (AMLs) were obtained by encapsulation of the nanoparticles in liposomes. FRET (Förster resonance energy transfer) experiments were performed to study the non-specific interactions between aqueous magnetoliposomes and giant unilamellar vesicles (GUVs), as models of cell membranes. It was possible to detect membrane fusion between GUVs and AMLs containing both NBD-C6-HPC (donor) and the dye Nile Red (acceptor).This work was supported by FEDER through the COMPETE/QREN/EU Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project of CFUM [PEst-C/FIS/UI0607/2013 (F-COMP-01-0124-FEDER-022711)] and through the research project PTDC/QUI/81238/2006 (FCOMP-01-0124-FEDER-007467). FCT, POPH-QREN and FSE are acknowledged for the PhD grant of A.R.O. Rodrigues (SFRH/BD/90949/2012) and for financial support to MAP-Fis PhD Programme
Magnetic liposomes based on nickel ferrite and manganese ferrite nanoparticles for biomedical applications
In this work, nickel ferrite and manganese ferrite nanoparticles were synthesized and characterized. These nanoparticles were incorporated in liposomes for biomedical applications.Fundação para a Ciência e a Tecnologia (FCT
Magnetic liposomes based on nickel ferrite nanoparticles as nanocarriers for new potential antitumor compounds
Guided transport of biologically active molecules (most of them toxic and with systemic side
effects) to target specific sites in human body has been a focus of research in therapeutics in
the past years. Magnetoliposomes (liposomes entrapping magnetic nanoparticles) are of large
importance, as they can overcome many pharmacokinetics problems and can be guided and
localized to the therapeutic site of interest by external magnetic field gradients [1,2]. In this
work, nickel ferrite nanoparticles (NPs) with size distribution of 11±5 nm were obtained.
Synthesized NPs show superparamagnetic behaviour at room temperature (magnetic
squareness of 7.2×10-5 and coercivity field of 12 Oe), being suitable for biological applications.
These NPs were either entrapped in liposomes, originating aqueous magnetoliposomes
(AMLs), or covered with a lipid bilayer, forming dry magnetoliposomes (DMLs), the last ones
prepared by a new promising route. Recently, AMLs and DMLs containing nickel-based
nanoparticles were successfully prepared and characterized [3]. A potential antitumor
compound [4] was successfully incorporated into the lipid bilayer of magnetoliposomes. DMLs
structure was evaluated by FRET (Förster Resonance Energy Transfer) measurements
between the fluorescent-labeled lipids NBD-C12-HPC (donor) included in the second lipid layer
and rhodamine B DOPE (acceptor) in the first lipid layer. A FRET efficiency of 23% was
calculated, with a corresponding donor-acceptor distance (r) of 3.11 nm, confirming DMLs
structure. Preliminary assays of the non-specific interactions of both types of magnetoliposomes
with biological membranes (modeled by giant unilamellar vesicles, GUVs) were performed,
keeping in mind future applications of drug delivery using this type of magnetic systems.
Membrane fusion between magnetoliposomes and GUVs was confirmed by FRET.FCT - Fundação para a Ciência e a Tecnologia, PEst-C/FIS/UI0607/2013 (F-COMP-01-0124-FEDER-022711
Magnetoliposomes based on manganese ferrite nanoparticles as nanocarriers for antitumor drugs
Publicado em "NanoPT2016 book of abstracts"In this work, manganese ferrite (MnFe2O4) nanoparticles with superparamagnetic behaviour at room temperature and size distribution of 26 ± 5 nm, were obtained by coprecipitation method. Structural and magnetic properties of the nanoparticles (NPs) were evaluated by XRD, HR-TEM and SQUID. The synthesized NPs were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs).This work was supported by FEDER through the COMPETE/QREN/EU Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Projects of CFUM [PEst-C/FIS/UI0607/2013 (F-COMP-01-0124-FEDER-022711)] and CQ/UM [PEst-C/QUI/UI0686/2013 (FCOMP-01-0124-FEDER -022716)]. FCT, POPH-QREN and FSE are acknowledged for the PhD grant of A.R.O. Rodrigues (SFRH/BD/90949/2012) and for financial support to MAP-Fis PhD Programme
Magnetoliposomes based on manganese ferrite nanoparticles for guided transport of antitumor drugs
Publicado em "RICI6 abstract book"In this work, manganese ferrite nanoparticles with size distribution of 46 ± 17 nm and superparamagnetic behavior were synthesized by coprecipitation method. These magnetic nanoparticles were either entrapped in liposomes, originating aqueous magnetoliposomes (AMLs), or covered with a lipid bilayer, forming solid magnetoliposomes (SMLs).MAP-Fis PhD Programme, FEDER, COMPETE/QREN/EU for financial support to CFUM (PEst-C/FIS/UI0607/2013) and FCT and POPH/QREN for PhD grant (SFRH/BD/90949/2012)
Maternal γδ T cells shape offspring pulmonary type 2 immunity in a microbiota-dependent manner.
Immune development is profoundly influenced by vertically transferred cues. However, little is known about how maternal innate-like lymphocytes regulate offspring immunity. Here, we show that mice born from γδ T cell-deficient (TCRδ-/-) dams display an increase in first-breath-induced inflammation, with a pulmonary milieu selectively enriched in type 2 cytokines and type 2-polarized immune cells, when compared with the progeny of γδ T cell-sufficient dams. Upon helminth infection, mice born from TCRδ-/- dams sustain an increased type 2 inflammatory response. This is independent of the genotype of the pups. Instead, the offspring of TCRδ-/- dams harbors a distinct intestinal microbiota, acquired during birth and fostering, and decreased levels of intestinal short-chain fatty acids (SCFAs), such as pentanoate and hexanoate. Importantly, exogenous SCFA supplementation inhibits type 2 innate lymphoid cell function and suppresses first-breath- and infection-induced inflammation. Taken together, our findings unravel a maternal γδ T cell-microbiota-SCFA axis regulating neonatal lung immunity
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