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1.
Clin Res Cardiol ; 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38112744

RESUMO

INTRODUCTION: The eradication of ventricular tachycardia (VT) isthmus sites constitutes the minimal procedural endpoint for VT ablation procedures. Contemporary high-resolution computed tomography (CT) imaging, in combination with computer-assisted analysis and segmentation of CT data, facilitates targeted elimination of VT isthmi. In this context, inHEART offers digitally rendered three-dimensional (3D) cardiac models which allow preoperative planning for VT ablations in ischemic and non-ischemic cardiomyopathies. To date, almost no data have been collected to compare the outcomes of VT ablations utilizing inHEART with those of traditional ablation approaches. METHODS: The presented data are derived from a retrospective analysis of n = 108 patients, with one cohort undergoing VT ablation aided by late-enhancement CT and subsequent analysis and segmentation by inHEART, while the other cohort received ablation through conventional methods like substrate mapping and activation mapping. The ablations were executed utilizing a 3D mapping system (Carto3), with the mapping generated via the CARTO® PENTARAY™ NAV catheter and subsequently merged with the inHEART model, if available. RESULTS: Results showed more successful outcome of ablations for the inHEART group with lower VT recurrence (27% vs. 42%, p < 0.06). Subsequent analyses revealed that patients with ischemic cardiomyopathies appeared to derive a significant benefit from inHEART-assisted VT ablation procedures, with a higher rate of successful ablation (p = 0.05). CONCLUSION: Our findings indicate that inHEART-guided ablation is associated with reduced VT recurrence compared to conventional procedures. This suggests that employing advanced imaging and computational modeling in VT ablation may be valuable for VT recurrences.

2.
Geohealth ; 7(10): e2023GH000901, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37799773

RESUMO

The objective of this study was to identify spatial disparities in the distribution of cancer hotspots within Romania. Additionally, the research aimed to track prevailing trends in cancer prevalence and mortality according to a cancer type. The study covered the timeframe between 2008 and 2017, examining all 3,181 territorial administrative units. The analysis of spatial distribution relied on two key parameters. The first parameter, persistence, measured the duration for which cancer prevalence exceeded the 75th percentile threshold. Cancer prevalence refers to the total number of individuals in a population who have been diagnosed with cancer at a specific time point, including both newly diagnosed cases (occurrence) and existing cases. The second parameter, the time continuity of persistence, calculated the consecutive months during which cancer prevalence consistently surpassed the 75th percentile threshold. Notably, persistence of elevated values was also evident in lowland regions, devoid of any discernible direct connection to environmental conditions. In conclusion, this work bears substantial relevance to regional health policies, by aiding in the formulation of prevention strategies, while also fostering a deeper comprehension of the socioeconomic and environmental factors contributing to cancer.

3.
Eur Rev Med Pharmacol Sci ; 26(18): 6796-6804, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36196728

RESUMO

OBJECTIVE: Cardiovascular atherosclerotic comorbidities represent an important cause of morbidity and mortality in patients diagnosed with psoriatic arthritis. In both atherosclerosis and Psoriatic arthritis, inflammation plays a pivotal role. Psoriatic arthritis is considered as an independent risk factor for the development of atherosclerosis with accelerated evolution. Development of atherosclerosis is initiated by the endothelial cell dysfunction along with inflammation and insulin resistance. The main aim of the study was to evaluate the endothelial function in Psoriatic arthritis patients, and to identify if it is related to the insulin resistance and Psoriatic arthritis disease activity. PATIENTS AND METHODS: In this case-control study, a group of 32 age and gender matched healthy controls was formed and compared to the group of 32 Psoriatic arthritis patients. We assessed the following parameters: Disease Activity in Psoriatic Arthritis Score, Homeostatic Model Assessment for Insulin Resistance, serum levels of the tumor necrosis factor alpha (TNFα), and the endothelial dysfunction by means of the flow-mediated dilation at brachial artery. The Student's t-test, the Pearson correlation and the ANOVA test were used to perform the statistical analysis of the data obtained; p-value <0.05 was considered as statistically significant. RESULTS: Compared to the patients in the control group, TNFα and Homeostatic Model Assessment for Insulin Resistance were increased (p-value <0.001), and flow-mediated dilation at brachial artery was decreased (p-value <0.001) in the disease group. In Psoriatic arthritis patients, significant correlations were found between Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance (r=0.8143, p-value <0.001), and between Disease Activity in Psoriatic Arthritis Score and flow-mediated dilation at brachial artery % (r= -0.8376, p-value <0.001). Psoriatic arthritis patients treated with Methotrexate exhibited reduced values of Disease Activity in Psoriatic Arthritis Score and Homeostatic Model Assessment for Insulin Resistance and increased values of flow-mediated dilation at brachial artery, when compared with the untreated patients. CONCLUSIONS: Endothelial dysfunction is present in Psoriatic arthritis patients and has a significant correlation with both, the course of the disease and the insulin resistance.


Assuntos
Artrite Psoriásica , Aterosclerose , Resistência à Insulina , Artéria Braquial , Estudos de Casos e Controles , Endotélio Vascular , Humanos , Inflamação , Metotrexato , Fator de Necrose Tumoral alfa
4.
J Interv Card Electrophysiol ; 65(2): 491-497, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35748975

RESUMO

BACKGROUND: High-power short-duration (HPSD) radiofrequency ablation (RFA) is highly efficient and safe while reducing procedure and RF time in pulmonary vein isolation (PVI). The QDot™ catheter is a novel contact force ablation catheter that allows automated flow and power adjustments depending on the local tissue temperature to maintain a target temperature during 90 W/4 s lesions. We analysed intraprocedural data and periprocedural safety using the QDot-catheter in patients undergoing PVI for paroxysmal atrial fibrillation (PAF). METHODS: We included n = 48 patients undergoing PVI with the QDot-catheter with a temperature-controlled HPSD ablation mode with 90 W/4 s (TC-HPSD). If focal reconnection occurred besides repeat ablation, the ablation mode was changed to 50 W/15 s (QMode). N = 23 patients underwent cerebral MRI to detect silent cerebral lesions. RESULTS: Mean RF time was 8.1 ± 2.8 min, and procedure duration was 84.5 ± 30 min. The overall maximal measured catheter tip temperature was 52.0 °C ± 4.6 °C, mean overall applied current was 871 mA ± 44 mA and overall applied energy was 316 J ± 47 J. The mean local impedance drop was 12.1 ± 2.4 Ohms. During adenosine challenge, n = 14 (29%) patients showed dormant conduction. A total of n = 24 steam pops were detected in n = 18 patients (39.1%), while no pericardial tamponade occurred. No periprocedural thromboembolic complications occurred, while n = 4 patients (17.4%) showed silent cerebral lesion. CONCLUSIONS: TC-HPSD ablation with 90 W/4 s using the QDot-catheter led to a reduction of procedure and RF time, while no major complications occurred. Despite optimized temperature control and power adjustment, steam pops occurred in a rather high number of patients, while none of them leads to tamponade or to clinical or neurological deficits.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Humanos , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Temperatura , Vapor , Desenho de Equipamento , Ablação por Cateter/métodos , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Fibrilação Atrial/etiologia , Imageamento por Ressonância Magnética , Resultado do Tratamento
5.
Epidemiol Psychiatr Sci ; 31: e39, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35674122

RESUMO

AIMS: As refugees and asylum seekers are at high risk of developing mental disorders, we assessed the effectiveness of Self-Help Plus (SH + ), a psychological intervention developed by the World Health Organization, in reducing the risk of developing any mental disorders at 12-month follow-up in refugees and asylum seekers resettled in Western Europe. METHODS: Refugees and asylum seekers with psychological distress (General Health Questionnaire-12 ⩾ 3) but without a mental disorder according to the Mini International Neuropsychiatric Interview (M.I.N.I.) were randomised to either SH + or enhanced treatment as usual (ETAU). The frequency of mental disorders at 12 months was measured with the M.I.N.I., while secondary outcomes included self-identified problems, psychological symptoms and other outcomes. RESULTS: Of 459 participants randomly assigned to SH + or ETAU, 246 accepted to be interviewed at 12 months. No difference in the frequency of any mental disorders was found (relative risk [RR] = 0.841; 95% confidence interval [CI] 0.389-1.819; p-value = 0.659). In the per protocol (PP) population, that is in participants attending at least three group-based sessions, SH + almost halved the frequency of mental disorders at 12 months compared to ETAU, however so few participants and events contributed to this analysis that it yielded a non-significant result (RR = 0.528; 95% CI 0.180-1.544; p-value = 0.230). SH + was associated with improvements at 12 months in psychological distress (p-value = 0.004), depressive symptoms (p-value = 0.011) and wellbeing (p-value = 0.001). CONCLUSIONS: The present study failed to show any long-term preventative effect of SH + in refugees and asylum seekers resettled in Western European countries. Analysis of the PP population and of secondary outcomes provided signals of a potential effect of SH + in the long-term, which would suggest the value of exploring the effects of booster sessions and strategies to increase SH + adherence.


Assuntos
Transtornos Mentais , Angústia Psicológica , Refugiados , Transtornos de Estresse Pós-Traumáticos , Europa (Continente) , Comportamentos Relacionados com a Saúde , Humanos , Transtornos Mentais/epidemiologia , Refugiados/psicologia , Transtornos de Estresse Pós-Traumáticos/psicologia
6.
Sci Rep ; 11(1): 9591, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33953282

RESUMO

Three commercial powders of MgB2 were tested in vitro by MTS and LDH cytotoxicity tests on the HS27 dermal cell line. Depending on powders, the toxicity concentrations were established in the range of 8.3-33.2 µg/ml. The powder with the lowest toxicity limit was embedded into polyvinylpyrrolidone (PVP), a biocompatible and biodegradable polymer, for two different concentrations. The self-replenishing MgB2-PVP composite materials were coated on substrate materials (plastic foil of the reservoir and silicon tubes) composing a commercial urinary catheter. The influence of the PVP-reference and MgB2-PVP novel coatings on the bacterial growth of Staphylococcus aureus ATCC 25923, Enterococcus faecium DMS 13590, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, in planktonic and biofilm state was assessed in vitro at 6, 24, and 48 h of incubation time. The MgB2-PVP coatings are efficient both against planktonic microbes and microbial biofilms. Results open promising applications for the use of MgB2 in the design of anti-infective strategies for different biomedical devices and systems.


Assuntos
Antibacterianos/farmacologia , Derme/efeitos dos fármacos , Linhagem Celular , Materiais Revestidos Biocompatíveis/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/crescimento & desenvolvimento , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Humanos , Povidona/farmacologia , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento
7.
FASEB J ; 34(7): 8902-8919, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32519783

RESUMO

TOKs are outwardly rectifying K+ channels in fungi with two pore-loops and eight transmembrane spans. Here, we describe the TOKs from four pathogens that cause the majority of life-threatening fungal infections in humans. These TOKs pass large currents only in the outward direction like the canonical isolate from Saccharomyces cerevisiae (ScTOK), and distinct from other K+ channels. ScTOK, AfTOK1 (Aspergillus fumigatus), and H99TOK (Cryptococcus neoformans grubii) are K+ -selective and pass current above the K+ reversal potential. CaTOK (Candida albicans) and CnTOK (Cryptococcus neoformans neoformans) pass both K+ and Na+ and conduct above a reversal potential reflecting the mixed permeability of their selectivity filter. Mutations in CaTOK and ScTOK at sites homologous to those that open the internal gates in classical K+ channels are shown to produce inward TOK currents. A favored model for outward rectification is proposed whereby the reversal potential determines ion occupancy, and thus, conductivity, of the selectivity filter gate that is coupled to an imperfectly restrictive internal gate, permitting the filter to sample ion concentrations on both sides of the membrane.


Assuntos
Condutividade Elétrica , Ativação do Canal Iônico/fisiologia , Oócitos/fisiologia , Canais de Potássio/fisiologia , Potássio/metabolismo , Sequência de Aminoácidos , Animais , Candida albicans/genética , Candida albicans/crescimento & desenvolvimento , Candida albicans/metabolismo , Clonagem Molecular , Biologia Computacional , Cryptococcus neoformans/genética , Cryptococcus neoformans/crescimento & desenvolvimento , Cryptococcus neoformans/metabolismo , Potenciais da Membrana , Oócitos/citologia , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Homologia de Sequência , Xenopus laevis
8.
Food Res Int ; 120: 763-775, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31000296

RESUMO

Non-thermal food processing technologies are becoming more important in the organic food sector because, beyond preserving the organic feature, they could offer organic products with additional benefits in terms of enhanced nutritional content and healthiness as well as better sensory properties that could satisfy the more complex demands of organic consumers. Berries have a well-known health benefits and show increasing market shares in European markets while dehydration can increase the food convenience in terms of extended shelf-life. This study investigates for the first time organic consumers' stated preferences, attitudes and individual differences for a non-thermal organic processing technology. Specifically, we investigated consumers' preferences for organic dried strawberries varying in drying technology used, such as the most conventional (i.e. thermal) air drying and the most innovative (i.e. non-thermal) microwave drying, origin, price levels, and nutrient contents in three European countries: Norway, Romania and Turkey. Data from a total of 614 consumers were collected through an online choice experiment. Results show that on average consumers prefer organic dried strawberries produced with air drying technology that have national origin, with natural nutrient content and at low price, but country and individual differences are identified. Consumers who showed least rejection for microwave dried products are young, mostly from Norway and have higher positive attitudes towards new food technologies. Consumers who showed most rejection for microwave dried products are older, mostly from Turkey and have higher positive attitudes for organic, natural and ecological products. Organic producers who adopt microwave drying might better inform consumers about the characteristics, the process and highlight the nutritional benefits of such technology. Finally, this research informs policy makers about the need to define and regulate more clearly microwave drying as an organic technology, as well as to regulate labelling to ensure that consumers are not misled and correctly informed about the new technology.


Assuntos
Comportamento do Consumidor/estatística & dados numéricos , Dessecação/métodos , Manipulação de Alimentos/métodos , Preferências Alimentares , Alimentos Orgânicos/estatística & dados numéricos , Fragaria , Adolescente , Adulto , Idoso , Europa (Continente) , Feminino , Liofilização/métodos , Frutas , Humanos , Masculino , Micro-Ondas , Pessoa de Meia-Idade , Análise de Componente Principal , Adulto Jovem
9.
Nat Microbiol ; 4(6): 1014-1023, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30858573

RESUMO

Permeable (sandy) sediments cover half of the continental margin and are major regulators of oceanic carbon cycling. The microbial communities within these highly dynamic sediments frequently shift between oxic and anoxic states, and hence are less stratified than those in cohesive (muddy) sediments. A major question is, therefore, how these communities maintain metabolism during oxic-anoxic transitions. Here, we show that molecular hydrogen (H2) accumulates in silicate sand sediments due to decoupling of bacterial fermentation and respiration processes following anoxia. In situ measurements show that H2 is 250-fold supersaturated in the water column overlying these sediments and has an isotopic composition consistent with fermentative production. Genome-resolved shotgun metagenomic profiling suggests that the sands harbour diverse and specialized microbial communities with a high abundance of [NiFe]-hydrogenase genes. Hydrogenase profiles predict that H2 is primarily produced by facultatively fermentative bacteria, including the dominant gammaproteobacterial family Woeseiaceae, and can be consumed by aerobic respiratory bacteria. Flow-through reactor and slurry experiments consistently demonstrate that H2 is rapidly produced by fermentation following anoxia, immediately consumed by aerobic respiration following reaeration and consumed by sulfate reduction only during prolonged anoxia. Hydrogenotrophic sulfur, nitrate and nitrite reducers were also detected, although contrary to previous hypotheses there was limited capacity for microalgal fermentation. In combination, these experiments confirm that fermentation dominates anoxic carbon mineralization in these permeable sediments and, in contrast to the case in cohesive sediments, is largely uncoupled from anaerobic respiration. Frequent changes in oxygen availability in these sediments may have selected for metabolically flexible bacteria while excluding strict anaerobes.


Assuntos
Bactérias/genética , Bactérias/metabolismo , Fermentação , Sedimentos Geológicos/microbiologia , Hipóxia , Bactérias Anaeróbias/metabolismo , Ciclo do Carbono , Gammaproteobacteria/metabolismo , Hidrogênio/metabolismo , Hidrogenase/classificação , Hidrogenase/genética , Metagenômica , Microbiota , Nitratos/metabolismo , Nitritos/metabolismo , Oceanos e Mares , Oxirredução , RNA Ribossômico 16S , Sulfatos/metabolismo
10.
Mater Sci Eng C Mater Biol Appl ; 71: 322-334, 2017 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-27987714

RESUMO

The novel Ti-20Zr-5Ta-2Ag alloy was characterised concerning its microstructure, morphology, mechanical properties, its passive film composition and thickness, its long-term electrochemical stability, corrosion resistance, ion release rate in Ringer solution of acid, neutral and alkaline pH values and antibacterial activity. The new alloy has a crystalline α microstructure (by XRD). Long-term XPS and SEM analyses show the thickening of the passive film and the deposition of hydroxyapatite in neutral and alkaline Ringer solution. The values of the electrochemical parameters confirm the over time stability of the new alloy passive film. All corrosion parameters have very favourable values in time which attest a high resistance to corrosion. Impedance spectra evinced a bi-layered passive film formed by the barrier, insulating layer and the porous layer. The monitoring of the open circuit potentials indicated the stability of the protective layers and their thickening in time. The new alloy releases (by ICP-MS measurements) very low quantities of Ti, Zr, Ag ions and no Ta ions. The new alloy exhibits a low antibacterial activity.


Assuntos
Ligas/química , Antibacterianos/química , Implantes Experimentais , Prata/química , Titânio/química , Zircônio/química , Fatores de Tempo
11.
Sci Rep ; 6: 31947, 2016 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-27535168

RESUMO

High precision measurements of molecules containing more than one heavy isotope may provide novel constraints on element cycles in nature. These so-called clumped isotope signatures are reported relative to the random (stochastic) distribution of heavy isotopes over all available isotopocules of a molecule, which is the conventional reference. When multiple indistinguishable atoms of the same element are present in a molecule, this reference is calculated from the bulk (≈average) isotopic composition of the involved atoms. We show here that this referencing convention leads to apparent negative clumped isotope anomalies (anti-clumping) when the indistinguishable atoms originate from isotopically different populations. Such statistical clumped isotope anomalies must occur in any system where two or more indistinguishable atoms of the same element, but with different isotopic composition, combine in a molecule. The size of the anti-clumping signal is closely related to the difference of the initial isotope ratios of the indistinguishable atoms that have combined. Therefore, a measured statistical clumped isotope anomaly, relative to an expected (e.g. thermodynamical) clumped isotope composition, may allow assessment of the heterogeneity of the isotopic pools of atoms that are the substrate for formation of molecules.

12.
Mater Sci Eng C Mater Biol Appl ; 63: 628-36, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27040258

RESUMO

Carboxymethyl guar gum (CMGG) synthesized from commercially available polysaccharide was formulated into nanoparticles via ionic gelation using trisodium trimetaphosphate (STMP) as cross-linking agent. Characterisation using a range of analytical techniques (FTIR, NMR, GPC, TGA and DLS) confirmed the CMGG structure and revealed the effect of the CMGG and STMP concentration on the main characteristics of the obtained nanoformulations. The average nanoparticle diameter was found to be around 208 nm, as determined by dynamic light scattering (DLS) and confirmed by scanning electron microscopy (SEM) and nanoparticle tracking analysis (NTA). Experiments using simulated gastric and intestinal fluids evidenced significant pH-dependent drug release behaviour of the nanoformulations loaded with Rhodamine B (RhB) as a model drug (loading capacity in excess of 83%), as monitored by UV-Vis. While dose-dependent cytotoxicity was observed, the nanoformulations appeared completely non-toxic at concentrations below 0.3 mg/mL. Results obtained so far suggest that carboxymethylated guar gum nanoparticles formulated with STMP warrant further investigations as polysaccharide based biocompatible drug nanocarriers.


Assuntos
Portadores de Fármacos/química , Galactanos/química , Mananas/química , Nanopartículas/química , Gomas Vegetais/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Reagentes de Ligações Cruzadas/química , Liberação Controlada de Fármacos , Difusão Dinâmica da Luz , Humanos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Tamanho da Partícula , Rodaminas/química , Rodaminas/metabolismo , Rodaminas/toxicidade , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
13.
Rev Med Chir Soc Med Nat Iasi ; 119(2): 484-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26204656

RESUMO

AIM: To evaluate intraocular biodistribution of fluorescent nanoparticles composed of dexamethasone bound to chitosan after intravitreal administration in rabbit eyes. MATERIAL AND METHODS: The chitosan and gelatin based nanoparticles were synthetized using a reverse emulsion-double crosslinking technique (ionic and covalent) and then dexamethasone was bound. Two units of 1% suspension of these nanoparticles in saline solution were injected intravitreally into rabbit eyes. The histologic sections obtained at 72 hours were analyzed by confocal microscopy. RESULTS: The chitosan-fluorescein conjugate bound to dexamethasone was present in all ocular tissues at 72 hours. The nanoparticles were present in the retina and lens in a larger amount than in the other ocular tissues. CONCLUSIONS: The reverse emulsion-double crosslinking technique was efficient in synthesizing a biocompatible polymeric nanosystem. The in vivo study of intraocular biodistribution of fluorescein-marked nanoparticles capable of binding dexamethasone revealed their affinity for the retina and lens after intravitreal administration.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Quitosana/administração & dosagem , Dexametasona/administração & dosagem , Olho/metabolismo , Glucocorticoides/administração & dosagem , Injeções Intravítreas , Nanopartículas/administração & dosagem , Animais , Materiais Biocompatíveis/farmacocinética , Química Farmacêutica , Quitosana/farmacocinética , Cristalinas/metabolismo , Dexametasona/farmacocinética , Modelos Animais de Doenças , Glucocorticoides/farmacocinética , Microscopia de Fluorescência , Coelhos , Retina/metabolismo , Distribuição Tecidual , Corpo Vítreo/metabolismo
14.
Int J Biol Macromol ; 72: 614-23, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25239193

RESUMO

Flaxseed lignans are a natural source of useful biologically active components that show a diverse spectrum of health-promoting properties. The valuable effects of the phenolic molecules are mainly due to their antioxidant activity by preventing oxidative stress and stimulate collagen synthesis, therefore, providing benefits to the skin. The present work highlights the development of flaxseed extract formulation as novel wound healing agent. The recognition of key structural features within flaxseed extract was crucial for the design and development of the therapeutic cream. Chromatographic analyses were employed for bioactive compounds identification and quantification. Folin-Ciocalteu method determined the total phenolic content and the antioxidant properties were evaluated by DPPH assay. The storage and loss modulus and tan δ were calculated for cream rheological properties evaluation. In vitro diffusion capacity and in vivo wound healing activity of phenolic cream were evaluated on Wistar rats. The collective properties and healing effect of the flaxseed suggested wound healing capacity.


Assuntos
Lignanas/administração & dosagem , Estresse Oxidativo/efeitos dos fármacos , Fenóis/química , Cicatrização/efeitos dos fármacos , Animais , Antioxidantes/administração & dosagem , Antioxidantes/química , Química Farmacêutica , Linho/química , Lignanas/química , Fenóis/administração & dosagem , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Ratos , Reologia , Pele/efeitos dos fármacos , Pele/patologia
15.
J Biol Chem ; 290(2): 889-903, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25425649

RESUMO

The calcium-activated chloride channel ANO1 regulates multiple physiological processes. However, little is known about the mechanism of channel gating and regulation of ANO1 activity. Using a high-throughput, random mutagenesis-based variomics screen, we generated and functionally characterized ∼6000 ANO1 mutants and identified novel mutations that affected channel activity, intracellular trafficking, or localization of ANO1. Mutations such as S741T increased ANO1 calcium sensitivity and rendered ANO1 calcium gating voltage-independent, demonstrating a critical role of the re-entrant loop in coupling calcium and voltage sensitivity of ANO1 and hence in regulating ANO1 activation. Our data present the first unbiased and comprehensive study of the structure-function relationship of ANO1. The novel ANO1 mutants reported have diverse functional characteristics, providing new tools to study ANO1 function in biological systems, paving the path for a better understanding of the function of ANO1 and its role in health and diseases.


Assuntos
Canais de Cloreto/metabolismo , Canais Iônicos/metabolismo , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Relação Estrutura-Atividade , Animais , Anoctamina-1 , Células CHO , Canais de Cloreto/química , Canais de Cloreto/genética , Cricetulus , Células HEK293 , Humanos , Canais Iônicos/química , Canais Iônicos/genética , Mutagênese Sítio-Dirigida , Proteínas de Neoplasias/genética , Conformação Proteica
16.
Phys Chem Chem Phys ; 16(47): 25896-905, 2014 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-25355433

RESUMO

The study proposes modeling calcein release kinetics (considered as a hydrophilic drug model) from an interpenetrating network matrix of hydrogels, based on the combination of two polymers, of which chitosan is the most commonly used polymer. The release process is analyzed for different increasing time intervals, based on the evolution of the release kinetics. For each time interval, a dominant release mechanism was identified and quantitative analyses were performed, to probe the existence of four distinct stages during its evolution with each stage governed by a different kinetics model. An interesting and original aspect, which is analyzed through a novel approach, is that of drug release at longer time scales, which is often overlooked. It revealed that the system behaves as a complex one and its evolution can be described through a nonlinear theoretical model, which offers us new insights into its order-disorder evolution.


Assuntos
Quitosana/química , Fluoresceínas/química , Hidrogéis/química , Cinética , Modelos Moleculares
17.
J Nanosci Nanotechnol ; 14(7): 5473-9, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24758052

RESUMO

The photoluminescence properties and formation mechanism of a novel stoichiometric phosphor are presented. Nanoplates of pure single-phase crystalline Eu2O2CO3 oxycarbonate (hexagonal type-II) were synthesized by dry autoclaving under autogenic pressure (under 3 MPa) using an efficient, high yield solid state green-chemistry route that can be extended to other rare-earth oxycarbonate and oxide systems, resulting in the full conversion of a simple commercial precursor in single-crystalline nanoplates with strong visible luminescence. Phosphors made of an oxide host and an active luminescent dopant ion are the commercial standard (i.e., Y2O3:Eu). It is generally considered that the activity of luminescent species, such as Eu3+, is quenched and disappears above a certain concentration of them in the lattice (concentration quenching). The truly stoichoimetric oxycarbonate phosphor without active dopant ions exhibits very strong red emission when excited by different excitations, in the UV and visible range, without any concentration quenching effect. The bright red light emission spectra of the of the photo-excited phosphor nanoplates under UV and visible light excitation is compared with that of a standard Y2O3:Eu commercial red phosphor powder, and the thermal conversion mechanism is proposed to obtain the single-phase stable stoichiometric oxycarbonate nanoplates.

18.
Mater Sci Eng C Mater Biol Appl ; 35: 291-9, 2014 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-24411380

RESUMO

This paper presents the synthesis and characterization of gellan gum derivatives containing quaternary ammonium groups, with the purpose of obtaining particulate controlled release systems for ciprofloxacin. Quaternized gellan derivatives were synthesized by grafting N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride onto gellan primary hydroxyl groups by nucleophilic substitution, in the presence of alkali, under specific reaction conditions using various gellan/N-(3-chloro-2-hydroxypropyl)-trimethyl ammonium chloride molar ratios. Degree of quaternization was determined by (1)H NMR spectroscopy and AgNO3 conductometric titration. Thermal behavior was investigated for all materials by thermogravimetric analysis. A study of the degree of quaternization and effect of the reaction conditions upon activation energy of quaternized gellan derivatives for the main degradation step by applying the Kissinger method at four heating rates is also reported. The novelty that this work brings refers to obtaining quaternized gellan and chitosan based particles with retention of quaternary ammonium moieties' antibacterial activity. In vitro transdermal release tests of ciprofloxacin from loaded particles were carried out on rat skin in isotonic phosphate buffer solution (pH=7.43). Ciprofloxacin was released up to 24 h, confirming quaternized gellan-chitosan particles' potential as controlled release systems for topical dermal applications.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Ciprofloxacina/administração & dosagem , Ciprofloxacina/farmacocinética , Preparações de Ação Retardada/síntese química , Polissacarídeos Bacterianos/química , Compostos de Amônio Quaternário/síntese química , Absorção Cutânea/fisiologia , Administração Tópica , Animais , Antibacterianos/administração & dosagem , Antibacterianos/síntese química , Antibacterianos/farmacocinética , Sobrevivência Celular/efeitos dos fármacos , Ciprofloxacina/química , Preparações de Ação Retardada/administração & dosagem , Difusão , Teste de Materiais , Ratos
19.
Biopolymers ; 101(3): 228-36, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23784667

RESUMO

Maleic anhydride (CMA) and itaconic anhydride modified collagen (CITA) were prepared as precursors for production of interpenetrated polymer networks (IPN). Calculated values for Huggins coefficient in aqueous diluted and semi-diluted solutions of modified collagen indicated a slightly tendency of aggregation for itaconic anhydride-modified collagen. In semi-diluted solution collagen (Coll) and CMA present slightly differences in the thixotropic behavior, while CITA has a pronounced thixotropic behavior. Flow and oscillatory measurements revealed an elastic behavior of the collagen solutions, pure and modified with MA or ITA, as the storage modulus (G') has always a superior value compared with the loss modulus (G″). The denaturation temperature (Td) of unmodified collagen increased from 34°C to 40°C for CMA and to 39°C for CITA respectively, by formation of covalent bonds that stabilize the triple helix.


Assuntos
Anidridos , Reologia , Anidridos/química , Colágeno/química , Soluções , Temperatura , Viscosidade
20.
J Nanosci Nanotechnol ; 14(8): 6394-8, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25936124

RESUMO

We prepared solid spheres, with diameters between 100 and 400 nm, encapsulating silver nanocrystallites (about 20 ± 10 nm in diameter), by heating colloidal solutions of silver in methoxyethanol at 120 °C. Stable coatings were obtained using spin coating and rapid thermal processing on optical glass substrates. UV-Vis spectroscopy measurements demonstrated the remarkable stability against aggregation and particle growth, even after prolonged heating at 120 °C and exposed at direct sunlight, of the solutions, even using high concentrations of silver (1 M), and coatings of spheres encapsulating silver.

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