34 research outputs found
EPIDURAL BLOOD PATCH IN SPONTANEOUS INTRACRANIAL HYPOTENSION
Background: Spontaneous Intracranial Hypotension (SIH) is a rare condition caused by a spinal cerebrospinal fluid (CSF) leak. It is usually described as an orthostatic headache, frequently associated with neck pain, nausea, vomiting, diplopia, blurred vision and distorted hearing. Initial treatment consists of bed rest, fluid supplementation, caffeine and analgesics. If conservative treatment fails, an epidural blood patch (EBP) therapy should be considered.
Methods: A healthy 31-year-old female patient presented with a spontaneous occipital headache during the expulsive period of a miscarriage. Six days later, she was referred to Neurology due to worsening symptoms (orthostatic headache, vertigo and diplopia). CAT scan, lumbar puncture and carotid ecodoppler were normal. Magnetic Resonance Imaging (MRI) revealed an epidural CSF collection suggesting a CSF fistula. After 21 days of conservative treatment and no clinical improvement, she was referred to Anaesthesiology to perform a lumbar EBP. Hospital discharged occurred five days later with no symptoms. The follow-up MRI was normal.
Discussion: Treatment of SIH aims to maintain CSF volume. The effect of EBP is twofold: an early effect related to volume replacement and a latent effect that results from sealing the leak. Symptomatic relief is usually obtained in few days but EBP may be repeated if symptoms recur. Complications such as transient paraesthesia, radicular pain, repeated inadvertent dural puncture and epidural infection are possible but rare.
Conclusions: The high success rate and the low incidence of complications have established the EBP as the best available treatment of SIH refractory to conservative measures
Magnetoliposomes based on magnetite nanoparticles
In this work, magnetic nanoparticles of magnetite were prepared by soft chemical methods, using different surfactants as templating media. These nanoparticles were either covered with a lipid bilayer, forming dry magnetoliposomes, or entrapped in liposomes - aqueous magnetoliposomes.FCT, FEDER, COMPETE/QREN/EU for financial support to CFUM (Strategic Project PEst-C/FIS/UI0607/2011) and to the research project PTDC/QUI/81238/2006 (FCOMP-01-0124-FEDER-007467)
Development of nickel-based magnetoliposomes
Liposomes entrapping nickel-based magnetic nanoparticles (magnetoliposomes) were prepared and characterized.This work was supported by FEDER through the COMPETE Program and by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Project of CFUM [PEst-C/FIS/UI0607/2011 (F-COMP-01-0124-FEDER-022711)]. FCT is also acknowledged for the PhD grant of A.R.O. Rodrigues (SFRH/BD/90949/2012)
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
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 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)
Magnetoliposomes based on nickel/silica core/shell nanoparticles
In this work, magnetic nanoparticles of nickel core with silica shell were prepared by soft chemical methods, using tetraethyl orthosilicate (TEOS) and different surfactants as templating media.
These nanoparticles were either covered with a lipid bilayer or entrapped in liposomes.FCT, FEDER, COMPETE/QREN/EU for financial support to CFUM (Strategic Project PEst-C/FIS/UI0607/2011) and to the research project PTDC/QUI/81238/2006 (FCOMP-01-0124-FEDER-007467)
Conservation Biogeography of the Sahara‐Sahel: additional protected areas are needed to secure unique biodiversity
Aim Identification of priority conservation areas and evaluation of coverage of
the current protected areas are urgently needed to halt the biodiversity loss.
Identifying regions combining similar environmental traits (climate regions)
and species assemblages (biogroups) is needed for conserving the biodiversity
patterns and processes. We identify climate regions and biogroups and map
species diversity across the Sahara-Sahel, a large geographical area that exhibits
wide environmental heterogeneity and multiple species groups with distinct
biogeographical affinities, and evaluate the coverage level of current network of
protected areas for biodiversity conservation.
Location Sahara-Sahel, Africa.
Methods We use spatially explicit climate data with the principal component
analysis and model-based clustering techniques to identify climate regions.
We use distributions of 1147 terrestrial vertebrates (and of 125 Sahara-Sahel
endemics) and apply distance clustering methods to identify biogroups for
both species groups. We apply reserve selection algorithms targeting 17% of
species distribution, climate regions and biogroups to identify priority areas
and gap analysis to assess their representation within the current protected
areas.
Results Seven climate regions were identified, mostly arranged as latitudinal
belts. Concentrations of high species richness were found in the Sahel, but the
central Sahara gathers most endemic and threatened species. Ten biogroups
(five for endemics) were identified. A wide range of biogroups tend to overlap
in specific climate regions. Identified priority areas are inadequately represented
in protected areas, and six new top conservation areas are needed to achieve
conservation targets.
Main conclusions Biodiversity distribution in Sahara-Sahel is spatially structured and apparently related to environmental variation. Although the majority of priority conservation areas are located outside the areas of intense
human activities, many cross multiple political borders and require internationally coordinated efforts for implementation and management. Optimized
biodiversity conservation solutions at regional scale are needed. Our work
contradicts the general idea that deserts are uniform areas and provide
options for the conservation of endangered species.info:eu-repo/semantics/publishedVersio