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1.
World J Surg ; 46(12): 2910-2918, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36064868

RESUMO

BACKGROUND: Pilonidal disease can be a debilitating condition which carries a significant physical and economic burden. This systematic review and updated meta-analysis presents the evidence for the use of platelet-rich plasma (PRP) for wound healing following open and minimally-invasive sacrococcygeal pilonidal surgery. METHODS: A literature search was performed during December 2021 for studies relating to platelet-rich plasma and pilonidal wound healing following surgery. RESULTS: Nine studies remained after applying the exclusion criteria, incorporating a total of 621 (open surgery group) and 309 (minimally-invasive group) patients, respectively. Pooled analysis of the six open surgery group studies demonstrated a significant reduction in wound healing time (mean difference [MD] = - 13.98 days, 95% CI - 18.41 to - 9.55, p < 0.001, I2 = 98%). Three open surgery group studies compared post-operative time off work, while three recorded mean pain duration; pooled analysis also revealed a significant reduction in both outcomes, respectively (MD = - 8.7 days, 95% CI - 9.4 to - 8.0, p < 0.001, I2 = 57%; MD = - 9.5 days, 95% CI - 15.6 to - 3.3, p = 0.002, I2 = 98%). Methodological heterogeneity among the minimally-invasive studies precluded formal meta-analysis; however, two studies demonstrated a modest improvement in wound healing when treated with PRP. CONCLUSIONS: This systematic review and updated meta-analysis provide further evidence supporting the use of PRP for wound healing in sacrococcygeal pilonidal disease. PRP application was demonstrated to significantly reduce healing time, postoperative pain and time off work in the open surgery group. Nevertheless, there is still considerable heterogeneity among PRP manufacture and administration techniques, and further high-powered RCTs with consistent methodology are required to substantiate these findings.


Assuntos
Seio Pilonidal , Plasma Rico em Plaquetas , Humanos , Seio Pilonidal/cirurgia , Cicatrização , Procedimentos Cirúrgicos Minimamente Invasivos
2.
J Microsc ; 267(2): 227-236, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28394445

RESUMO

In this work, a new tool was developed, the MORIA program that readily translates Rutherford backscattering spectrometry (RBS) output data into visual information, creating a display of the distribution of elements in a true three-dimensional (3D) environment. The program methodology is illustrated with the analysis of yeast Saccharomyces cerevisiae cells, exposed to copper oxide nanoparticles (CuO-NP) and HeLa cells in the presence of gold nanoparticles (Au-NP), using different beam species, energies and nuclear microscopy systems. Results demonstrate that for both cell types, the NP internalization can be clearly perceived. The 3D models of the distribution of CuO-NP in S. cerevisiae cells indicate the nonuniform distribution of NP in the cellular environment and a relevant confinement of CuO-NP to the cell wall. This suggests the impenetrability of certain cellular organelles or compartments for NP. By contrast, using a high-resolution ion beam system, discretized agglomerates of Au-NP were visualized inside the HeLa cell. This is consistent with the mechanism of entry of these NPs in the cellular space by endocytosis enclosed in endosomal vesicles. This approach shows RBS to be a powerful imaging technique assigning to nuclear microscopy unparalleled potential to assess nanoparticle distribution inside the cellular volume.

3.
J Mater Sci Mater Med ; 27(4): 69, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26886817

RESUMO

The incidence of bone disorders, whether due to trauma or pathology, has been trending upward with the aging of the worldwide population. The currently available treatments for bone injuries are rather limited, involving mainly bone grafts and implants. A particularly promising approach for bone regeneration uses rapid prototyping (RP) technologies to produce 3D scaffolds with highly controlled structure and orientation, based on computer-aided design models or medical data. Herein, tricalcium phosphate (TCP)/alginate scaffolds were produced using RP and subsequently their physicochemical, mechanical and biological properties were characterized. The results showed that 60/40 of TCP and alginate formulation was able to match the compression and present a similar Young modulus to that of trabecular bone while presenting an adequate biocompatibility. Moreover, the biomineralization ability, roughness and macro and microporosity of scaffolds allowed cell anchoring and proliferation at their surface, as well as cell migration to its interior, processes that are fundamental for osteointegration and bone regeneration.


Assuntos
Regeneração Óssea/fisiologia , Osteoblastos/fisiologia , Alicerces Teciduais , Materiais Biocompatíveis/farmacologia , Cálcio/metabolismo , Linhagem Celular , Humanos , Microscopia Eletrônica de Varredura , Fósforo/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Propriedades de Superfície
4.
Biometals ; 28(2): 367-80, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25725797

RESUMO

Burkholderia cenocepacia is a bacterial pathogen which causes severe respiratory infections in cystic fibrosis (CF). These studies were aimed at gaining an insight into the iron acquisition strategies of B. cenocepacia. In iron restricted conditions, genes associated with the synthesis and utilisation of ornibactin (pvdA, orbA, orb F) were significantly upregulated compared to the expression of pyochelin associated genes (pchD, fptA). In the absence of alternative iron sources, B. cenocepacia J2315 and 715j utilised ferritin and haemin, but not transferrin or lactoferrin for growth. Significantly, mutants unable to produce ornibactin, (715j-orbI) or ornibactin and pyochelin, (715j-pobA), utilised haemin and ferritin more efficiently than the wild-type. Moreover, both mutants were also able to utilise lactoferrin for growth (P ≤ 0.01) and additionally 715j-pobA utilised transferrin (P ≤ 0.01), potentially facilitating adaptation to the host environment. Furthermore, B. cenocepacia increased ornibactin gene expression in response to pyoverdine from Pseudomonas aeruginosa (P ≤ 0.01), demonstrating the capacity to compete for iron in co-colonised niches. Pyoverdine also significantly diminished the growth of B. cenocepacia (P < 0.001) which was related to its iron chelating activity. In a study of three B. cenocepacia sequential clonal isolates obtained from a CF patient over a 3.5 year period, ornibactin upregulation in response to pyoverdine was less pronounced in the last isolate compared to the earlier isolates, as was growth in the presence of haemin and ferritin, indicating alternative iron acquisition mechanism(s) may dominate as chronic infection progresses. These data demonstrate the multifaceted iron acquisition strategies of B. cenocepacia and their capacity to be differentially activated in the presence of P. aeruginosa and during chronic infection.


Assuntos
Burkholderia cenocepacia/metabolismo , Ferro/metabolismo , Sideróforos/genética , Adaptação Fisiológica , Infecções por Burkholderia/microbiologia , Burkholderia cenocepacia/genética , Fibrose Cística/microbiologia , Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Heme/metabolismo , Humanos , Pneumonia Bacteriana/microbiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/fisiologia , Sideróforos/biossíntese , Ativação Transcricional
5.
Nanotechnology ; 24(27): 275101, 2013 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-23759860

RESUMO

Bridging the gap between nanoparticulate delivery systems and translational gene therapy is a long sought after requirement in nanomedicine-based applications. However, recent developments regarding nanoparticle functionalization have brought forward the ability to synthesize materials with biofunctional moieties that mimic the evolved features of viral particles. Herein we report the versatile conjugation of both cell penetrating arginine and pH-responsive histidine moieties into the chitosan polymeric backbone, to improve the physicochemical characteristics of the native material. Amino acid coupling was confirmed by 2D TOCSY NMR and Fourier transform infrared spectroscopy. The synthesized chitosan-histidine-arginine (CH-H-R) polymer complexed plasmid DNA biopharmaceuticals, and spontaneously assembled into stable 105 nm nanoparticles with spherical morphology and positive surface charge. The functionalized delivery systems were efficiently internalized into the intracellular compartment, and exhibited remarkably higher transfection efficiency than unmodified chitosan without causing any cytotoxic effect. Additional findings regarding intracellular trafficking events reveal their preferential escape from degradative lysosomal pathways and nuclear localization. Overall, this assembly of nanocarriers with bioinspired moieties provides the foundations for the design of efficient and customizable materials for cancer gene therapy.


Assuntos
Arginina/análogos & derivados , Quitosana/análogos & derivados , DNA/administração & dosagem , Histidina/análogos & derivados , Nanopartículas/química , Transfecção , DNA/genética , Células HeLa , Humanos , Concentração de Íons de Hidrogênio , Nanopartículas/ultraestrutura , Plasmídeos/administração & dosagem , Plasmídeos/genética
6.
New Phytol ; 195(2): 356-371, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22578268

RESUMO

• The activation of high-affinity root transport systems is the best-conserved strategy employed by plants to cope with low inorganic phosphate (Pi) availability, a role traditionally assigned to Pi transporters of the Pht1 family, whose respective contributions to Pi acquisition remain unclear. • To characterize the Arabidopsis thaliana Pht1;9 transporter, we combined heterologous functional expression in yeast with expression/subcellular localization studies and reverse genetics approaches in planta. Double Pht1;9/Pht1;8 silencing lines were also generated to gain insight into the role of the closest Pht1;9 homolog. • Pht1;9 encodes a functional plasma membrane-localized transporter that mediates high-affinity Pi/H⁺ symport activity in yeast and is highly induced in Pi-starved Arabidopsis roots. Null pht1;9 alleles exhibit exacerbated responses to prolonged Pi limitation and enhanced tolerance to arsenate exposure, whereas Pht1;9 overexpression induces the opposite phenotypes. Strikingly, Pht1;9/Pht1;8 silencing lines display more pronounced defects than the pht1;9 mutants. • Pi and arsenic plant content analyses confirmed a role of Pht1;9 in Pi acquisition during Pi starvation and arsenate uptake at the root-soil interface. Although not affecting plant internal Pi repartition, Pht1;9 activity influences the overall Arabidopsis Pi status. Finally, our results indicate that both the Pht1;9 and Pht1;8 transporters function in sustaining plant Pi supply on environmental Pi depletion.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Fosfatos/metabolismo , Fósforo/deficiência , Raízes de Plantas/metabolismo , Adaptação Fisiológica/efeitos dos fármacos , Adaptação Fisiológica/genética , Arabidopsis/efeitos dos fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Arseniatos/toxicidade , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Genes de Plantas/genética , Fenótipo , Proteínas de Transporte de Fosfato/genética , Fósforo/farmacologia , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/genética , Plantas Geneticamente Modificadas , Simportadores de Próton-Fosfato/metabolismo , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/metabolismo , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo
7.
Nanotechnology ; 22(1): 015101, 2011 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-21135452

RESUMO

The encapsulation of DNA inside nanoparticles meant for gene delivery applications is a challenging process where several parameters need to be modulated in order to design nanocapsules with specific tailored characteristics. The purpose of this study was to investigate and improve the formulation parameters of plasmid DNA (pDNA) loaded in chitosan nanocapsules using tripolyphosphate (TPP) as polyanionic crosslinker. Nanocapsule morphology and encapsulation efficiency were analyzed as a function of chitosan degree of deacetylation and chitosan-TPP ratio. The manipulation of these parameters influenced not only the particle size but also the encapsulation and release of pDNA. Consequently the transfection efficiency of the nanoparticulated systems was also enhanced with the optimization of the particle characteristics. Overall, the differently formulated nanoparticulated systems possess singular properties that can be employed according to the desired gene delivery application.


Assuntos
Quitosana/química , DNA/química , Terapia Genética/métodos , Nanoconjugados/química , Plasmídeos/química , Polifosfatos/química , Acetilação , Análise de Variância , Linhagem Celular Tumoral , Química Farmacêutica/métodos , Quitosana/administração & dosagem , Reagentes de Ligações Cruzadas/química , DNA/administração & dosagem , DNA/farmacocinética , Eletroforese em Gel de Ágar , Técnicas de Transferência de Genes , Humanos , Microscopia Eletrônica de Varredura , Microscopia de Fluorescência , Nanocápsulas , Nanoconjugados/administração & dosagem , Nanotecnologia/métodos , Tamanho da Partícula , Plasmídeos/administração & dosagem , Plasmídeos/farmacocinética , Difração de Raios X
8.
Anal Biochem ; 397(1): 37-47, 2010 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-19766583

RESUMO

Recombinant monoclonal antibodies undergo extensive posttranslational modifications. In this article, we characterize major modifications, separated by cation exchange chromatography, on an immunoglobulin G1 (IgG1) monoclonal antibody (mAb). We found that N-terminal cyclization of glutamine residues to pyroglutamate on the light and heavy chains are the major isoforms resolved during cation exchange chromatography. However, using CEX, we also separated and identified isoforms with unpaired cysteine residues in the V(H) domain of the molecule (Cys22-Cys96). Omalizumab, a therapeutic anti-IgE antibody, has unpaired cysteine residues in the V(H) domain between Cys22 and Cys96, and the Fab fragment, containing the unpaired cysteine residues, is reported to have reduced potency. Dynamic interchain disulfide rearrangement, with slow kinetics, was recently reported to take place in serum for an IgG2 molecule and resulted in predictable mature isoforms. Analytical evaluation of our mAb, after recovery from serum, revealed that the unpaired intrachain cysteine residues (Cys22-Cys96) reformed their disulfide bond. The significance of this study is that correct pairing occurred rapidly, and we speculate that thiol molecules such as cysteine, homocysteine, and glutathione in serum provide an environment, outside the endoplasmic reticulum, for correct linkage.


Assuntos
Dissulfetos/química , Imunoglobulina G/química , Região Variável de Imunoglobulina/química , Anticorpos Anti-Idiotípicos , Anticorpos Monoclonais/química , Anticorpos Monoclonais Humanizados , Cromatografia por Troca Iônica , Dissulfetos/metabolismo , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/isolamento & purificação , Imunoglobulina G/sangue , Cadeias Pesadas de Imunoglobulinas/química , Cadeias Leves de Imunoglobulina/química , Omalizumab , Papaína/metabolismo , Processamento de Proteína Pós-Traducional , Ácido Pirrolidonocarboxílico/química , Proteínas Recombinantes/química
9.
Gynecol Obstet Invest ; 70(4): 322-7, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21109742

RESUMO

Candida spp. are common causative agents of mucocutaneous infections. New therapeutic antifungal drugs are needed to treat chronic disease as these are frequently clinically resistant to azols. Chitosan, among other possible vehicles for active compounds, shows an added value as it appears to have intrinsic antimicrobial properties. The aim of the present study was to evaluate the anti-Candida activity of a medium-molecular-weight chitosan hydrogel (CH), to clarify its possible mechanism of action and to evaluate its cytotoxicity on human fibroblasts. CH antifungal activity was assessed according to CLSI reference M27-A3 protocol; its mechanism of action was investigated by flow cytometry, and its cytotoxicity was studied by MTT assay. CH demonstrated a full inhibition of C. tropicalis, C. krusei, C. guilliermondii and C. parapsilosis growth while impairing C. albicans and C. glabrata viability. Flow cytometry tests showed that CH acts by inducing primary lesion of the cytoplasmic membrane. However, CH showed no cytotoxic effect upon human fibroblasts cells. Resistant strains will require new therapeutic approaches. Chitosan being a good carrier and having itself anti-Candida activity seems to be a promising vehicle to be used for the treatment of mucocutaneous candidosis.


Assuntos
Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Quitosana/farmacologia , Hidrogéis/farmacologia , Morte Celular , Divisão Celular/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Quitosana/toxicidade , Fibroblastos/efeitos dos fármacos , Citometria de Fluxo , Humanos , Hidrogéis/toxicidade , Cinética
10.
J Cell Biol ; 146(4): 831-42, 1999 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-10459017

RESUMO

Cells adhere to the substratum through specialized structures that are linked to the actin cytoskeleton. Recent studies report that adhesion also involves the intermediate filament (IF) and microtubule cytoskeletons, although their mechanisms of interaction are unknown. Here we report evidence for a novel adhesion-dependent interaction between components of the actin and IF cytoskeletons. In biochemical fractionation experiments, fimbrin and vimentin coprecipitate from detergent extracts of macrophages using vimentin- or fimbrin-specific antisera. Fluorescence microscopy confirms the biochemical association. Both proteins colocalized to podosomes in the earliest stages of cell adhesion and spreading. The complex is also found in filopodia and retraction fibers. After detergent extraction, fimbrin and vimentin staining of podosomes, filopodia, and retraction fibers are lost, confirming that the complex is localized to these structures. A 1:4 stoichiometry of fimbrin binding to vimentin and a low percentage (1%) of the extracted vimentin suggest that fimbrin interacts with a vimentin subunit. A fimbrin-binding site was identified in the NH(2)-terminal domain of vimentin and the vimentin binding site at residues 143-188 in the CH1 domain of fimbrin. Based on these observations, we propose that a fimbrin-vimentin complex may be involved in directing the assembly of the vimentin cytoskeleton at cell adhesion sites.


Assuntos
Actinas/metabolismo , Citoesqueleto/metabolismo , Macrófagos/citologia , Glicoproteínas de Membrana/metabolismo , Proteínas dos Microfilamentos , Vimentina/metabolismo , Animais , Sítios de Ligação , Adesão Celular , Linhagem Celular , Polaridade Celular , Tamanho Celular , Filamentos Intermediários/metabolismo , Macrófagos/metabolismo , Macrófagos/ultraestrutura , Glicoproteínas de Membrana/química , Glicoproteínas de Membrana/genética , Camundongos , Microscopia de Fluorescência , Modelos Moleculares , Peso Molecular , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/metabolismo , Polímeros , Ligação Proteica , Pseudópodes/metabolismo , Deleção de Sequência , Vimentina/química , Vimentina/genética
11.
Eur J Clin Microbiol Infect Dis ; 27(11): 1101-11, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18600352

RESUMO

The treatment of cystic fibrosis (CF) patients chronically infected with Burkholderia cepacia complex (Bcc) bacteria requires extensive and aggressive antibiotics therapy, exposing these bacteria to prolonged antibiotics-selective pressure. In the present study, we have compared the susceptibility patterns to 13 antimicrobials of 94 Bcc isolates obtained from 15 Portuguese CF patients in the course of chronic infection during a five-year survey. These isolates were previously genotyped and represent 11 different strains of the species B. cenocepacia (subgroups A and B), B. cepacia, B. multivorans, and B. stabilis. The results are consistent with the notion that CF Bcc isolates are resistant to the most clinically relevant antimicrobials and suggest an uneven distribution of resistance rates among the different species, with B. cenocepacia subgroup A isolates being the most resistant. Phenotypic variants exhibiting differences in the antimicrobial susceptibility patterns were obtained from the sputum samples of clinically deteriorated CF patients during chronic lung infection. The isolation of resistant variants coincided with periods of pulmonary exacerbation and antibiotics therapy.


Assuntos
Infecções por Burkholderia/microbiologia , Complexo Burkholderia cepacia/efeitos dos fármacos , Complexo Burkholderia cepacia/isolamento & purificação , Fibrose Cística/complicações , Pneumonia/microbiologia , Adolescente , Adulto , Antibacterianos/farmacologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , Humanos , Lactente , Testes de Sensibilidade Microbiana , Portugal , Escarro/microbiologia
12.
Rev Esp Anestesiol Reanim (Engl Ed) ; 65(3): 149-153, 2018 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28967439

RESUMO

Mechanical ventilation in thoracic surgery has undergone significant changes in recent years due to the implementation of the protective ventilation. This review will analyze recent ventilatory strategies in one-lung ventilation. A MEDLINE research was performed using Mesh term "One-Lung Ventilation" including randomized clinical trials, metanalysis, reviews and systematic reviews published in the last 6 years. Search was performed on 21st March 2017. A total of 75 articles were initially found. After title and abstract review 14 articles were included. Protective ventilation is not simply synonymous of low tidal volume ventilation, but it also includes routine use of PEEP and alveolar recruitment maneuver. New techniques are still in discussion namely PEEP adjustment, ratio inspiration:expiration, ideal type of anesthesia during one-lung ventilation and hypercapnic ventilation.


Assuntos
Ventilação Monopulmonar/métodos , Anestesia por Inalação , Animais , Humanos , Hipercapnia , Metanálise como Assunto , Modelos Animais , Respiração com Pressão Positiva/métodos , Atelectasia Pulmonar/prevenção & controle , Ensaios Clínicos Controlados Aleatórios como Assunto , Suínos , Volume de Ventilação Pulmonar
13.
Colloids Surf B Biointerfaces ; 159: 7-15, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-28778063

RESUMO

Coaxial electrospinning is a technique that allows the production of nanofibers with a core-shell structure. Such fibers present several advantages as materials for the preparation of scaffolds, namely due to the possibility of combining a core with the desired mechanical properties with a shell prepared from biocompatible materials that will establish proper interactions with the host. Herein, core-shell fibrous meshes, composed of a polycaprolactone (PCL) core and a functionalized gelatin shell, were prepared by coaxial electrospinning and then photocrosslinked under UV light aiming to be used in vascular tissue regeneration. The suitability of the meshes for the pretended biomedical application was evaluated by assessing their chemical/physical properties as well as their haemo and biocompatibility in vitro. The obtained results revealed that meshes' shell prepared with a higher content of gelatin showed fibers with diameters presenting a unimodal distribution and a mean value of 600nm. Moreover, those fibers with higher content of gelatin also displayed lower water contact angles, and therefore higher hydrophilicities. Such features are crucial for the good biologic performance displayed by these meshes, when in contact with blood and with Normal Human Dermal Fibroblasts cells.


Assuntos
Gelatina/química , Poliésteres/química , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Materiais Biocompatíveis/química , Teste de Materiais
14.
J Clin Neurosci ; 45: 257-260, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28844615

RESUMO

Multiple Sclerosis (MS) treatment with natalizumab is associated with Progressive Multifocal Leukoencephalopathy (PML). The risk of PML being related to the anti-JCV antibody index is well established, but there is less known about seroconversion rates in natalizumab-treated patients and longitudinal variation in the anti-JCV antibody index. Our objective was to assess anti-JCV antibody prevalence in an MS population and to evaluate the evolution of the anti-JCV antibody index in natalizumab-treated patients. To assess anti-JCV antibody prevalence, we included all patients who had the anti-JCV antibody test in our consultation, regardless of the treatment. To evaluate the evolution of the anti-JCV antibody index and seroconversion, only natalizumab-treated patients with at least two samples were selected. Demographic characteristics were evaluated. From a total of 371 patients included, 68.19% (n=253) were seropositive for anti-JCV antibodies (JCV+). There was a significant difference in anti-JCV antibody seropositivity concerning gender (male 76.27% vs. female 64.43%, p=0.023), but not age. To evaluate seroconversion, 85 patients who were initially seronegative (JCV-) were selected. The annual rate of seroconversion in the first two years was stable, but after that there was a significant increase with treatment duration (ρ=0.90, p=0.037): in the first year it was 5.88% (n=5/85); in the second, 5.71% (n=4/70); in the third, 6.82% (n=3/44); in the fourth, 10.34% (n=3/29); and in the fifth, 15.0% (n=3/20). The mean index variability was higher in patients who experienced seroconversion (1.16±0.97), followed by JCV+ patients (0.44±0.48), compared to JCV- patients (0.08±0.05). In conclusion, anti-JCV antibody prevalence in our population is comparable to other reported cohorts. The seroconversion rate increased with treatment duration. We found a high fluctuation in the antibody index in JCV+ patients.


Assuntos
Anticorpos Antivirais/sangue , Fatores Imunológicos/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Natalizumab/efeitos adversos , Soroconversão , Adulto , Feminino , Humanos , Vírus JC/imunologia , Leucoencefalopatia Multifocal Progressiva/induzido quimicamente , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/imunologia , Prevalência , Estudos Retrospectivos , Caracteres Sexuais
15.
Int Immunopharmacol ; 46: 105-111, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28282574

RESUMO

OBJECTIVES: Natalizumab long-term effectiveness data in real-world relapsing-remitting multiple sclerosis (RRMS) is needed. Our objective is to report the long-term effectiveness and safety of natalizumab in a cohort of RRMS patients. METHODS: This is a retrospective study of natalizumab treatment for two years or longer in RRMS. Annualized relapse rate, Expanded Disability Status Scale (EDSS), brain magnetic resonance imaging T2 lesion volume, JC virus antibody status, previous treatments and adverse events were analysed. RESULTS: Seventy-one patients were included with a mean treatment duration of 44.86±17.39months. Over the treatment duration there was a significant decrease in annualized relapse rate (88.37%) and EDSS (28.57%); no evidence of clinical disease activity in 73.24% and 61.97% after one and two-years respectively; and brain magnetic resonance imaging T2 lesion volume remained stable. Forty patients suspended natalizumab, in 85% due to high risk of developing progressive multifocal leukoencephalopathy (PML). The major complication was PML (n=3). CONCLUSIONS: Natalizumab showed effectiveness in the long-term follow up period of our cohort, with reduction of ARR, EDSS, and MRI lesion load stabilization. PML was the major complication.


Assuntos
Encéfalo/efeitos dos fármacos , Leucoencefalopatia Multifocal Progressiva/prevenção & controle , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Natalizumab/uso terapêutico , Adolescente , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Leucoencefalopatia Multifocal Progressiva/diagnóstico , Leucoencefalopatia Multifocal Progressiva/etiologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente/complicações , Esclerose Múltipla Recidivante-Remitente/diagnóstico , Portugal , Estudos Retrospectivos , Risco , Suspensão de Tratamento , Adulto Jovem
16.
Colloids Surf B Biointerfaces ; 156: 95-103, 2017 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-28531880

RESUMO

Intraocular lenses (IOLs) present an alternative for extended, local drug delivery in the prevention of post-operative acute endophthalmitis. In the present work, we modified the surface of a hydrophilic acrylic material, used for manufacturing of IOLs, through plasma-assisted grafting copolymerization of 2-acrylamido-2-methylpropane sulfonic acid (AMPS) or [2-(methacryloyloxy)ethyl]dimethyl-(3-sulfopropyl)ammonium hydroxide (SBMA), with the aim of achieving a controlled and effective drug release. The material was loaded with moxifloxacin (MFX), a commonly used antibiotic for endophthalmitis prevention. The characterization of the modified material showed that relevant properties, like swelling capacity, wettability, refractive index and transmittance, were not affected by the surface modification. Concerning the drug release profiles, the most promising result was obtained when AMPS grafting was done in the presence of MFX. This modification led to a higher amount of drug being released for a longer period of time, which is a requirement for the prevention of endophthalmitis. The material was found to be non-cytotoxic for rabbit corneal endothelial cells. In a second step, prototype IOLs were modified with AMPS and loaded with MFX as previously and, after sterilization and storage (30days), they were tested under dynamic conditions, in a microfluidic cell with volume and renovation rate similar to the eye aqueous humour. MFX solutions collected in this assay were tested against Staphylococcus aureus and Staphylococcus epidermidis and the released antibiotic proved to be effective against both bacteria until the 12th day of release.


Assuntos
Antibacterianos/administração & dosagem , Argônio , Fluoroquinolonas/administração & dosagem , Lentes Intraoculares , Gases em Plasma , Polímeros/química , Animais , Microscopia Eletrônica de Varredura , Moxifloxacina , Coelhos , Propriedades de Superfície
17.
Clin Nutr ; 36(1): 49-64, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27642056

RESUMO

BACKGROUND: A lack of agreement on definitions and terminology used for nutrition-related concepts and procedures limits the development of clinical nutrition practice and research. OBJECTIVE: This initiative aimed to reach a consensus for terminology for core nutritional concepts and procedures. METHODS: The European Society of Clinical Nutrition and Metabolism (ESPEN) appointed a consensus group of clinical scientists to perform a modified Delphi process that encompassed e-mail communication, face-to-face meetings, in-group ballots and an electronic ESPEN membership Delphi round. RESULTS: Five key areas related to clinical nutrition were identified: concepts; procedures; organisation; delivery; and products. One core concept of clinical nutrition is malnutrition/undernutrition, which includes disease-related malnutrition (DRM) with (eq. cachexia) and without inflammation, and malnutrition/undernutrition without disease, e.g. hunger-related malnutrition. Over-nutrition (overweight and obesity) is another core concept. Sarcopenia and frailty were agreed to be separate conditions often associated with malnutrition. Examples of nutritional procedures identified include screening for subjects at nutritional risk followed by a complete nutritional assessment. Hospital and care facility catering are the basic organizational forms for providing nutrition. Oral nutritional supplementation is the preferred way of nutrition therapy but if inadequate then other forms of medical nutrition therapy, i.e. enteral tube feeding and parenteral (intravenous) nutrition, becomes the major way of nutrient delivery. CONCLUSION: An agreement of basic nutritional terminology to be used in clinical practice, research, and the ESPEN guideline developments has been established. This terminology consensus may help to support future global consensus efforts and updates of classification systems such as the International Classification of Disease (ICD). The continuous growth of knowledge in all areas addressed in this statement will provide the foundation for future revisions.


Assuntos
Desnutrição/diagnóstico , Desnutrição/terapia , Política Nutricional , Terminologia como Assunto , Caquexia/complicações , Consenso , Dieta , Nutrição Enteral , Fragilidade/complicações , Humanos , Avaliação Nutricional , Estado Nutricional , Obesidade/complicações , Sobrepeso/complicações , Nutrição Parenteral , Sarcopenia/complicações , Sociedades Científicas
18.
Artigo em Inglês | MEDLINE | ID: mdl-16946483

RESUMO

The cloning, expression, purification, crystallization and preliminary crystallographic analysis of glucose-1-phosphate uridylyltransferase (UgpG) from Sphingomonas elodea ATCC 31461 bound to glucose-1-phosphate are reported. Diffraction data sets were obtained from seven crystal forms in five different space groups, with highest resolutions ranging from 4.20 to 2.65 A. The phase problem was solved for a P2(1) crystal form using multiple isomorphous replacement with anomalous scattering from an osmium derivative and a SeMet derivative. The best native crystal in space group P2(1) has unit-cell parameters a = 105.5, b = 85.7, c = 151.8 A, beta = 105.2 degrees . Model building and refinement are currently under way.


Assuntos
Proteínas de Bactérias/química , Glucofosfatos/metabolismo , Sphingomonas/enzimologia , Sphingomonas/genética , UTP-Glucose-1-Fosfato Uridililtransferase/química , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Sítios de Ligação/genética , Clonagem Molecular , Cristalização , Cristalografia por Raios X/métodos , Regulação Bacteriana da Expressão Gênica , Glucofosfatos/química , Glucofosfatos/genética , Especificidade por Substrato/genética , UTP-Glucose-1-Fosfato Uridililtransferase/biossíntese , UTP-Glucose-1-Fosfato Uridililtransferase/genética
19.
Virulence ; 7(5): 558-77, 2016 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-27191378

RESUMO

The Cek1 MAP kinase (MAPK) mediates vegetative growth and cell wall biogenesis in the fungal pathogen Candida albicans. Alterations in the fungal cell wall caused by a defective Cek1­mediated signaling pathway leads to increased ß­1,3­glucan exposure influencing dectin­1 fungal recognition by immune cells. We show here that cek1 cells also display an increased exposure of α­1,2 and ß­1,2­mannosides (α­M and ß­M), a phenotype shared by strains defective in the activating MAPKK Hst7, suggesting a general defect in cell wall assembly. cek1 cells display walls with loosely bound material as revealed by transmission electron microscopy and are sensitive to tunicamycin, an inhibitor of N­glycosylation. Transcriptomal analysis of tunicamycin treated cells revealed a differential pattern between cek1 and wild type cells which involved mainly cell wall and stress related genes. Mapping α­M and ß­M epitopes in the mannoproteins of different cell wall fractions (CWMP) revealed an important shift in the molecular weight of the mannan derived from mutants defective in this MAPK pathway. We have also assessed the role of galectin­3, a member of a ß­galactoside­binding protein family shown to bind to and kill C. albicans through ß­M recognition, in the infection caused by cek1 mutants. Increased binding of cek1 to murine macrophages was shown to be partially blocked by lactose. Galectin-3(-/-) mice showed increased resistance to fungal infection, although galectin-3 did not account for the reduced virulence of cek1 mutants in a mouse model of systemic infection. All these data support a role for the Cek1­mediated pathway in fungal cell wall maintenance, virulence and antifungal discovery.


Assuntos
Candida albicans/imunologia , Parede Celular/química , Proteínas Fúngicas/metabolismo , Manosídeos/imunologia , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Animais , Candida albicans/efeitos dos fármacos , Candida albicans/genética , Candida albicans/patogenicidade , Candidíase/microbiologia , Parede Celular/efeitos dos fármacos , Parede Celular/imunologia , Parede Celular/metabolismo , Modelos Animais de Doenças , Proteínas Fúngicas/genética , Galectina 3/genética , Galectina 3/metabolismo , Perfilação da Expressão Gênica , Regulação Fúngica da Expressão Gênica , Sistema de Sinalização das MAP Quinases , Manosídeos/química , Camundongos , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Tunicamicina/farmacologia , Virulência , beta-Glucanas/imunologia
20.
Int J Biol Macromol ; 93(Pt B): 1539-1548, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27185071

RESUMO

Cardiovascular disease is the leading cause of morbidity and mortality among industrialized countries. Vascular grafts are often required for the surgical treatments. Considering the limitations associated with the use of autografts and with the currently available synthetic materials, a growing demand in tissue engineered vascular grafts has been registered. During the work here described, electrospinning technique was used to prepared fibrous matrices to be applied as vascular implants. For that purpose, electrospun polycaprolactone (PCL) fibrous mats were produced and afterwards coated with different hydrogel formulations based in photocrosslinkable gelatin (GelMA) and the macromers poly(ethylene glycol) acrylate (PEGA) and poly(ethylene glycol) diacrylate (PEGDA). These were further photocrosslinked under UV irradiation using Irgacure® 2959 (by BASF) as the photoinitiator. The suitability of the coated scaffolds for the intended application, was evaluated by assessing their chemical/physical properties as well as their interaction with blood and endothelial cells.


Assuntos
Prótese Vascular , Gelatina/química , Poliésteres/química , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Bioprótese , Células Cultivadas , Técnicas Eletroquímicas , Teste de Materiais , Polietilenoglicóis/química , Polimerização , Coelhos , Propriedades de Superfície , Engenharia Tecidual , Raios Ultravioleta
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