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1.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-38072359

RESUMO

BACKGROUND: Thiopurines such as azathioprine (AZA) and mercaptopurine (MP) are commonly utilized to treat inflammatory bowel disease (IBD). Their use is frequently restricted due to gastrointestinal intolerance (GI). Previous retrospective studies have reported that AZA-intolerant patients may benefit from a switch to MP; yet the effectiveness of this strategy has not been prospectively evaluated. AIMS: To assess GI tolerance to MP in patients who are intolerant to AZA, and to identify clinical predictors of GI intolerance to AZA or MP. METHODS: A prospective, observational, single-cohort study was performed in 92 thiopurine-naïve IBD patients. They were started on a 50mg dose of AZA and escalated to 2.5mg/kg per day by week 2. Those with GI intolerance were rechallenged with a 50% dose of AZA, after which another dose escalation attempt was made. If symptoms persisted, they were switched to MP. RESULTS: Thirty (32.6%) of the recruited patients suffered from GI intolerance to AZA. Of these, 15 did not present recurrence of symptoms after rechallenge with lower doses. Of 15 intolerant patients, 14 were switched to MP. Within the MP cohort, 8 patients (57%) were also intolerant to MP, 5 (36%) had no symptoms, and 1 (7%) was lost to follow-up. Female gender was the only independent predictor of GI intolerance to AZA. CONCLUSIONS: Up to half of the AZA-intolerant patients tolerated a 50% dose rechallenge that was successfully escalated. A switch to MP was tolerated in over a third of cases whom rechallenge failed. Our strategy (challenge-rechallenge-switch) achieved an overall GI tolerance to thiopurines in most of the patients.

2.
Int J Mol Sci ; 23(14)2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35886980

RESUMO

The emergence of antibiotic resistant bacteria coupled with the shortage of efficient antibacterials is one of the most serious unresolved problems for modern medicine. In this study, the nano-hybridization of the clinically relevant antibiotic, gentamicin, with the bacterial pro-pathological cell-to-cell communication-quenching enzyme, acylase, is innovatively employed to increase its antimicrobial efficiency against Pseudomonas aeruginosa planktonic cells and biofilms. The sonochemically generated hybrid gentamicin/acylase nano-spheres (GeN_AC NSs) showed a 16-fold improved bactericidal activity when compared with the antibiotic in bulk form, due to the enhanced physical interaction and disruption of the P. aeruginosa cell membrane. The nano-hybrids attenuated 97 ± 1.8% of the quorum sensing-regulated virulence factors' production and inhibited the bacterium biofilm formation in an eight-fold lower concentration than the stand-alone gentamicin NSs. The P. aeruginosa sensitivity to GeN_AC NSs was also confirmed in a real time assay monitoring the bacterial cells elimination, using a quartz crystal microbalance with dissipation. In protein-enriched conditions mimicking the in vivo application, these hybrid nano-antibacterials maintained their antibacterial and antibiofilm effectiveness at concentrations innocuous to human cells. Therefore, the novel GeN_AC NSs with complementary modes of action show potential for the treatment of P. aeruginosa biofilm infections at a reduced antibiotic dosage.


Assuntos
Pseudomonas aeruginosa , Percepção de Quorum , Antibacterianos/farmacologia , Biofilmes , Gentamicinas/farmacologia , Humanos
3.
Int J Mol Sci ; 23(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36012396

RESUMO

Current procedures for the assessment of chronic wound infection are time-consuming and require complex instruments and trained personnel. The incidence of chronic wounds worldwide, and the associated economic burden, urge for simple and cheap point-of-care testing (PoCT) devices for fast on-site diagnosis to enable appropriate early treatment. The enzyme myeloperoxidase (MPO), whose activity in infected wounds is about ten times higher than in non-infected wounds, appears to be a suitable biomarker for wound infection diagnosis. Herein, we develop a single-component foldable paper-based device for the detection of MPO in wound fluids. The analyte detection is achieved in two steps: (i) selective immunocapture of MPO, and (ii) reaction of a specific dye with the captured MPO, yielding a purple color with increasing intensity as a function of the MPO activity in infected wounds in the range of 20-85 U/mL. Ex vivo experiments with wound fluids validated the analytic efficiency of the paper-based device, and the results strongly correlate with a spectrophotometric assay.


Assuntos
Líquidos Corporais , Infecção dos Ferimentos , Colorimetria , Corantes , Humanos , Papel , Testes Imediatos , Infecção dos Ferimentos/diagnóstico
4.
Gastroenterol Hepatol ; 45(9): 697-705, 2022 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-34508808

RESUMO

BACKGROUND: COVID-19 pandemic increased medical services demand aside from interrupting daily clinical practice for other diseases such as inflammatory bowel disease (IBD). Here we present the results of a survey to gain the perception of IBD specialists in their patient-management using telemedicine in their daily practice. METHODS: This was an observational survey study among physicians focused on IBD (gastroenterologist, surgeons, and pediatricians) members of the Spanish Working Group on Crohn's Disease and Ulcerative Colitis (GETECCU), the Spanish Association of Gastroenterology (AEG), and the Spanish Association of Coloproctology (AECP), regarding changes of management of IBD patients. RESULTS: We received a total of 269 responses to the survey (from May to June 2020). Before the pandemic, nearly all the respondents reported performing very frequently their visits face-to-face (n=251, 93.3%) while, during the pandemic, the telephone visits were the most frequent visits performed (n=138, 51.3%). Regarding communication difficulties, 157 (58.4%) respondents reported the impossibility of performing a proper examination as the most relevant issue. Also, 114 (42.4%) respondents considered remote visits more time-consuming than face-to-face visits. Most gastroenterologists (n=188, 83.2%) considered patients with active perianal disease in special need of face-to-face consultation and more than half of the surgeons (n=35, 50.7%) reported having performed an immediate postoperative follow-up remotely. CONCLUSIONS: Most IBD units have implemented remote visits during the pandemic, but most professionals found them more time-consuming and unsuitable for some disease profiles. Therefore, there is a need for the development of better telemedicine systems that can meet professionals' and patients' requirements.


Assuntos
COVID-19 , Doenças Inflamatórias Intestinais , Telemedicina , Humanos , Pandemias/prevenção & controle , Espanha/epidemiologia , Doenças Inflamatórias Intestinais/terapia , Doenças Inflamatórias Intestinais/epidemiologia , Doença Crônica
5.
Gen Physiol Biophys ; 39(2): 195-202, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32329447

RESUMO

The current strategies to eradicate bacteria require that the antimicrobial agent either penetrate or disrupt the bacterial membrane. In Escherichia coli (E.coli) as a model of Gram-negative strains, the antimicrobials have to cross two barriers - the outer and the inner membrane being the latter composed by ~ 77% phosphatidylethanolamine (PE), ~ 13% phosphatidylglycerol (PG) and ~ 10% cardiolipin (CL) lipids. Each one of these lipid families shares the same headgroup, but contains acyl chains with varying length and degree of unsaturation. Bacteria adapt their membrane lipid composition and metabolism in response to environmental signals, such as the temperature, resulting in different interactions with exogenous molecules, e.g. antibacterial agents. Herein, bacterial model membranes are prepared to evaluate the lipid-lipid interactions in Langmuir monolayers of binary mixtures at several molar ratios of PE and PG or CL at human physiological temperature (37°C). Both PE:PG and PE:CL monolayers were stable at 37°C and presented higher molecular areas (> 20 Å2/molecule) than at 23°C. However, these lipid mixtures presented liquid-expanded state and rigidity (inverse of the compressibility modulus ~ 90 mN/m) slightly lower than at 23°C. Such athermalicity at biologically relevant temperatures may favour the preservation of the biological functions of E.coli.


Assuntos
Membrana Externa Bacteriana/química , Temperatura Corporal , Escherichia coli , Lipídeos de Membrana/química , Cardiolipinas , Membrana Celular/química , Humanos , Fosfatidiletanolaminas , Fosfatidilgliceróis
6.
Int J Mol Sci ; 21(16)2020 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-32796622

RESUMO

Ascorbate oxidases are an enzyme group that has not been explored to a large extent. So far, mainly ascorbate oxidases from plants and only a few from fungi have been described. Although ascorbate oxidases belong to the well-studied enzyme family of multi-copper oxidases, their function is still unclear. In this study, Af_AO1, an enzyme from the fungus Aspergillus flavus, was characterized. Sequence analyses and copper content determination demonstrated Af_AO1 to belong to the multi-copper oxidase family. Biochemical characterization and 3D-modeling revealed a similarity to ascorbate oxidases, but also to laccases. Af_AO1 had a 10-fold higher affinity to ascorbic acid (KM = 0.16 ± 0.03 mM) than to ABTS (KM = 1.89 ± 0.12 mM). Furthermore, the best fitting 3D-model was based on the ascorbate oxidase from Cucurbita pepo var. melopepo. The laccase-like activity of Af_AO1 on ABTS (Vmax = 11.56 ± 0.15 µM/min/mg) was, however, not negligible. On the other hand, other typical laccase substrates, such as syringaldezine and guaiacol, were not oxidized by Af_AO1. According to the biochemical and structural characterization, Af_AO1 was classified as ascorbate oxidase with unusual, laccase-like activity.


Assuntos
Ascorbato Oxidase/metabolismo , Aspergillus flavus/enzimologia , Lacase/metabolismo , Sequência de Aminoácidos , Ascorbato Oxidase/química , Cobre/metabolismo , Cinética , Lacase/química , Modelos Moleculares , Oxirredução , Especificidade por Substrato
7.
J Med Internet Res ; 21(9): e15505, 2019 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-31538948

RESUMO

BACKGROUND: Although electronic health interventions are considered safe and efficient, evidence regarding the cost-effectiveness of telemonitoring in inflammatory bowel disease is lacking. OBJECTIVE: We aimed to evaluate the cost-effectiveness and cost-utility of the Telemonitorización de la Enfermedad de Crohn y Colitis Ulcerosa (Telemonitoring of Crohn's Disease and Ulcerative Colitis [TECCU]) Web platform (G_TECCU intervention group) for telemonitoring complex inflammatory bowel disease, compared with standard care (G_control) and nurse-assisted telephone care (G_NT intervention group). METHODS: We analyzed cost-effectiveness from a societal perspective by comparing the 3 follow-up methods used in a previous 24-week randomized controlled trial, conducted at a tertiary university hospital in Spain. Patients with inflammatory bowel disease who initiated immunosuppressants or biologic agents, or both, to control inflammatory activity were recruited consecutively. Data on the effects on disease activity (using clinical indexes) and quality-adjusted life-years (using the EuroQol 5 dimensions questionnaire) were collected. We calculated the costs of health care, equipment, and patients' productivity and social activity impairment. We compared the mean costs per patient, utilities, and bootstrapped differences. RESULTS: We included 63 patients (21 patients per group). TECCU saved €1005 (US $1100) per additional patient in remission compared with G_control (95% CI €-13,518 to 3137; US $-14,798 to 3434), with a 79.96% probability of being more effective at lower costs. Compared with G_NT, TECCU saved €2250 (US $2463) per additional patient in remission (95% CI €-15,363 to 11,086; US $-16,817 to 12,135), and G_NT saved €538 (US $589) compared with G_control (95% CI €-6475 to 5303; US $-7088 to 5805). G_TECCU and G_NT showed an 84% and 67% probability, respectively, of producing a cost saving per additional quality-adjusted life-year (QALY) compared with G_control, considering those simulations that involved negative incremental QALYs as well. CONCLUSIONS: There is a high probability that the TECCU Web platform is more cost-effective than standard and telephone care in the short term. Further research considering larger cohorts and longer time horizons is required. TRIAL REGISTRATION: ClinicalTrials.gov NCT02943538; https://clinicaltrials.gov/ct2/show/NCT02943538 (http://www. webcitation.org/746CRRtDN).


Assuntos
Colite Ulcerativa/economia , Colite Ulcerativa/epidemiologia , Análise Custo-Benefício/métodos , Doença de Crohn/economia , Doença de Crohn/epidemiologia , Telemedicina/métodos , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
8.
Biomacromolecules ; 19(9): 3628-3636, 2018 09 10.
Artigo em Inglês | MEDLINE | ID: mdl-30052024

RESUMO

In this study, freestanding nanobiocomposite films were obtained by the sequential deposition of biopolymer-capped silver nanoparticles (AgNPs) and hyaluronic acid (HA). At first, dispersions of AgNPs decorated with chitosan (CS) or aminocellulose (AC) were synthesized by applying high intensity ultrasound. These polycationic nanoentities were layer-by-layer assembled with the HA polyanion to generate stable 3D supramolecular constructs, where the biopolymer-capped AgNPs play the dual role of active agent and structural element. SEM images of the assemblies revealed gradual increase of thickness with the number of deposited bilayers. The composites of ≥50 bilayers were safe to human cells and demonstrated 100% antibacterial activity against Staphylococcus aureus and Escherichia coli. Moreover, the films containing CSAgNPs brought about the total prevention of biofilm formation reducing the cells surface adherence by up to 6 logs. Such nanobiocomposites could serve as an effective barrier to control bacterial growth on injured skin, burns, and chronic wounds.


Assuntos
Antibacterianos/química , Nanocompostos/química , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Celulose/análogos & derivados , Quitosana/análogos & derivados , Escherichia coli/efeitos dos fármacos , Ácido Hialurônico/química , Nanopartículas Metálicas/química , Prata/química , Staphylococcus aureus/efeitos dos fármacos
9.
J Med Internet Res ; 20(11): e11602, 2018 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-30482739

RESUMO

BACKGROUND: The reported efficacy of telemedicine in patients with inflammatory bowel disease (IBD) is inconsistent among studies, and data for complex IBD are lacking. OBJECTIVE: We aimed to evaluate the impact of remote monitoring using a Web system-Telemonitorización de la Enfermedad de Crohn y Colitis Ulcerosa or Telemonitoring of Crohn's Disease and Ulcerative Colitis (TECCU)-as compared to standard care and telephone care on health outcomes and health care in patients with complex IBD. METHODS: We performed a 3-arm randomized controlled trial. Adult patients with IBD who received immunosuppressants and biological agents were recruited from the IBD Unit of a tertiary university hospital. The patients were randomized into groups to receive remote monitoring (G_TECCU), nurse-assisted telephone care (G_NT), or standard care with in-person visits (G_control). All patients completed the study visits at baseline and at 12 and 24 weeks in addition to each type of intervention. The primary outcome was the percentage of patients in remission at 24 weeks. Secondary health outcomes were quality of life, medication adherence, adverse effects, satisfaction, and social activities. Data on the number of outpatient visits and telephone calls, emergency visits, hospitalizations, IBD-related surgeries, and corticosteroid courses were also collected. RESULTS: A total of 63 patients were selected (21 patients in each group). During the study, 90.5% (19/21) of patients in G_control, 95.2% (20/21) in G_NT, and 85.7% (18/21) in G_TECCU were compliant to the intervention. After 24 weeks, the percentage of patients in remission was higher in G_TECCU (17/21, 81%) than in G_NT (14/21, 66.7%) and G_control (15/21, 71.4%). A higher improvement in disease activity was observed in G_TECCU than in G_control in terms of the Harvey-Bradshaw/Mayo (odds ratio=0.12, 95% CI=0.003-2.162, P=.19) and Harvey-Bradshaw/Walmsley (odds ratio=0.11, 95% CI=0.004-1.55, P=.13) indexes. Improvement in disease activity was associated with a larger reduction in fecal calprotectin values in G_TECCU compared to G_control (estimated intervention effect: odds ratio=-0.90; 95% CI=-1.96 to 0.16, P=.11). All completers adhered to treatment in G_TECCU. In addition, the quality of life, social activities, and satisfaction improved in all 3 groups. Although the number of outpatient visits and telephone calls was lower in G_TECCU than in G_NT and G_control, the safety profile was similar in all 3 groups. CONCLUSIONS: This pilot clinical trial suggests that the TECCU Web-based system is a safe strategy for improving health outcomes in patients with complex IBD and reducing the use of health care resources. TRIAL REGISTRATION: ClinicalTrials.gov NCT02943538; https://clinicaltrials.gov/ct2/show/NCT02943538 (Archived by WebCite at http://www.webcitation.org/746CRRtDN).


Assuntos
Colite Ulcerativa/psicologia , Colite Ulcerativa/terapia , Doença de Crohn/psicologia , Doença de Crohn/terapia , Doenças Inflamatórias Intestinais/psicologia , Doenças Inflamatórias Intestinais/terapia , Qualidade de Vida/psicologia , Telemedicina/métodos , Adulto , Feminino , Humanos , Internet , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Adulto Jovem
10.
Biomacromolecules ; 18(5): 1544-1555, 2017 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-28421746

RESUMO

The healing of chronic wounds requires intensive medical intervention at huge healthcare costs. Dressing materials should consider the multifactorial nature of these wounds comprising deleterious proteolytic and oxidative enzymes and high bacterial load. In this work, multifunctional hydrogels for chronic wound application were produced by enzymatic cross-linking of thiolated chitosan and gallic acid. The hydrogels combine several beneficial to wound healing properties, controlling the matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) activities, oxidative stress, and bacterial contamination. In vitro studies revealed above 90% antioxidant activity, and MPO and collagenase inhibition by up to 98 and 23%, respectively. Ex vivo studies with venous leg ulcer exudates confirmed the inhibitory capacity of the dressings against MPO and MMPs. Additionally, the hydrogels reduced the population of the most frequently encountered in nonhealing wounds bacterial strains. The stable at physiological conditions and resistant to lysozyme degradation hydrogels showed high biocompatibility with human skin fibroblasts.


Assuntos
Bandagens , Quitosana/análogos & derivados , Hidrogéis/química , Cicatrização , Antibacterianos/química , Antibacterianos/farmacologia , Biocatálise , Células Cultivadas , Reagentes de Ligações Cruzadas/química , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Ácido Gálico/análogos & derivados , Humanos , Hidrogéis/síntese química , Hidrogéis/farmacologia , Hidrogéis/uso terapêutico , Metaloproteinases da Matriz/metabolismo , Estresse Oxidativo , Peroxidase/metabolismo , Compostos de Sulfidrila/química
11.
Eur Phys J E Soft Matter ; 40(6): 62, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28620696

RESUMO

Artificial lipid bilayers have been extensively studied as models that mimic natural membranes (biomimetic membranes). Several attempts of biomimetic membranes inserting ubiquinone (UQ) have been performed to enlighten which the position of UQ in the lipid layer is, although obtaining contradictory results. In this work, pure components (DPPC and UQ) and DPPC:UQ mixtures have been studied using surface pressure-area isotherms and Langmuir-Blodgett (LB) films of the same compounds have been transferred onto solid substrates being topographically characterized on mica using atomic force microscopy and electrochemically on indium tin oxide slides. DPPC:UQ mixtures present less solid-like physical state than pure DPPC indicating a higher-order degree for the latter. UQ influences considerably DPPC during the fluid state, but it is mainly expelled after the phase transition at [Formula: see text] 26 mN·m^-1 for the 5:1 ratio and at [Formula: see text] 21 mN·m^-1 for lower UQ content. The thermodynamic studies confirm the stability of the DPPC:UQ mixtures before that event, although presenting a non-ideal behaviour. The results indicate that UQ position can be tuned by means of the surface pressure applied to obtain LB films and the UQ initial content. The UQ positions in the biomimetic membrane are distinguished by their formal potential: UQ located in "diving" position with the UQ placed in the DPPC matrix in direct contact with the electrode surface ( -0.04±0.02 V), inserted between lipid chains without contact to the substrate ( 0.00±0.01 V) and parallel to the substrate, above the lipid chains ( 0.09±0.02 V).


Assuntos
Materiais Biomiméticos/química , Bicamadas Lipídicas/química , Ubiquinona/química , 1,2-Dipalmitoilfosfatidilcolina/química , Simulação de Dinâmica Molecular
12.
Appl Opt ; 56(18): 5258-5267, 2017 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-29047579

RESUMO

The control of surface errors as a function of spatial frequency is critical during the fabrication of modern optical systems. A large-scale surface figure error is controlled by a guided removal process, such as computer-controlled optical surfacing. Smaller-scale surface errors are controlled by polishing process parameters. Surface errors of only a few millimeters may degrade the performance of an optical system, causing background noise from scattered light and reducing imaging contrast for large optical systems. Conventionally, the microsurface roughness is often given by the root mean square at a high spatial frequency range, with errors within a 0.5×0.5 mm local surface map with 500×500 pixels. This surface specification is not adequate to fully describe the characteristics for advanced optical systems. The process for controlling and minimizing mid- to high-spatial frequency surface errors with periods of up to ∼2-3 mm was investigated for many optical fabrication conditions using the measured surface power spectral density (PSD) of a finished Zerodur optical surface. Then, the surface PSD was systematically related to various fabrication process parameters, such as the grinding methods, polishing interface materials, and polishing compounds. The retraceable experimental polishing conditions and processes used to produce an optimal optical surface PSD are presented.

13.
Gastroenterol Hepatol ; 40(9): 641-647, 2017 Nov.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-28797518

RESUMO

Inflammatory bowel disease (IBD) is a chronic and relapsing disorder with significant medical, social and financial impacts. IBD patients require continuous follow-up, and healthcare resource use in this context increases over time. In the last decade, telemedicine has influenced the treatment of chronic diseases like IBD via the application of information and communication technologies to provide healthcare services remotely. Telemedicine and its various applications (telemanagement, teleconsulting and tele-education) enable closer follow-up and provide education resources that promote patient empowerment, encouraging treatment optimisation over the entire course of the disease. We describe the impact of using telemedicine on IBD health outcomes and discuss the limitations of implementing these systems in the real-life management of IBD patients.


Assuntos
Doenças Inflamatórias Intestinais/terapia , Telemedicina , Humanos , Internet
14.
Biochim Biophys Acta ; 1848(6): 1341-51, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25771450

RESUMO

The photosynthesis is the process used by plants and bacteria cells to convert inorganic matter in organic thanks to the light energy. This process consist on several steps, being one of them the electronic transport from the photosystem II to the cytochrome thanks to plastoquinone-9 (PQ). Here we prepare membranes that mimic the characteristics and composition of natural photosynthetic cell membranes and we characterize them in order to obtain the PQ molecules position in the membrane and their electrochemical behaviour. The selected galactolipid is digalactosyldiacylglycerol (DGDG) that represents the 30% of the thylakoid membrane lipid content. The results obtained are worthful for several science fields due to the relevance of galactolipids as anti-algal, anti-viral, anti-tumor and anti-inflammatory agents and the antioxidant and free radical scavenger properties of prenylquinones. Both pure components (DGDG and PQ) and the DGDG:PQ mixtures have been studied using surface pressure-area isotherms. These isotherms give information about the film stability and indicate the thermodynamic behaviour of the mixture and their physical state. The Langmuir-Blodgett (LB) film has been transferred forming a monolayer that mimics the bottom layer of the biological membranes. This monolayer on mica has been topographically characterized using AFM and both the height and the physical state that they present have been obtained. Moreover, these monolayers have been transferred onto ITO that is a hydrophilic substrate with good optical and electrical features, so that, it is suitable for studying the electrochemical behaviour of these systems and it is a good candidate for energy producing devices.


Assuntos
Materiais Biomiméticos/química , Galactolipídeos/química , Plastoquinona/química , Eletroquímica , Eletrólitos/química , Microscopia de Força Atômica , Oxirredução , Pressão , Temperatura , Compostos de Estanho/química
16.
Eur Phys J E Soft Matter ; 39(3): 39, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27021656

RESUMO

The relevance of biomimetic membranes using galactolipids has not been expressed in any extensive experimental study of these lipids. Thus, on the one hand, we present an in-depth article about the presence and role of monogalactosyldiacylglycerol (MGDG) and digalactosyldiacylglycerol (DGDG) in thylakoid membranes, their physical states and their applications. On the other hand, we use the Langmuir and Langmuir-Blodgett (LB) techniques to prepare biomimetic monolayers of saturated galactolipids MGDG, DGDG and MGDG:DGDG 2:1 mixture (MD)--biological ratio--. These monolayers are studied using surface pressure-area isotherms and their data are processed to enlighten their physical states and mixing behaviour. These monolayers, once transferred to a solid substrate at several surface pressures are topographically studied on mica using atomic force microscopy (AFM) and using cyclic voltammetry for studying the electrochemical behaviour of the monolayers once transferred to indium-tin oxide (ITO), which has good optical and electrical properties. Moreover, MD presents other differences in comparison with its pure components that are explained by the presence of different kinds of galactosyl headgroups that restrict the optimal orientation of the MGDG headgroups.


Assuntos
Materiais Biomiméticos/química , Fenômenos Biofísicos , Galactolipídeos/química , Membrana Celular/química , Eletroquímica , Propriedades de Superfície , Tilacoides/química
18.
World J Gastroenterol ; 29(7): 1139-1156, 2023 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-36926667

RESUMO

This review summarizes the evidence about telemonitoring in patients with inflammatory bowel disease (IBD). To give an overview of the advances performed, as well as the enablers and barriers which favoured/hindered telemonitoring implementation. We performed a literature search in PubMed, EMBASE, MEDLINE, Cochrane Database, Web of Science and Conference Proceedings. Titles and abstracts published up to September 2022 were screened for a set of inclusion criteria: telemonitoring intervention, IBD as the main disease, and a primary study performed. Ninety-seven reports were selected for full review. Finally, 20 were included for data extraction and critical appraisal. Most studies used telemonitoring combined with tele-education, and programs evolved from home telemanagement systems towards web portals through mHealth applications. Web systems demonstrated patients' acceptance, improvement in quality of life, disease activity and knowledge, with a good cost-effectiveness profile in the short-term. Initially, telemonitoring was almost restricted to ulcerative colitis, but new patient reported outcome measures, home-based tests and mobile devices favoured its expansion to different patients´ categories. However, technological and knowledge advances led to legal, ethical, economical and logistic issues. Standardization of remote healthcare is necessary, to improve the interoperability of systems as well as to address liability concerns and users´ preferences. Telemonitoring IBD is well accepted and improves clinical outcomes at a lower cost in the short-term. Funders, policymakers, providers, and patients need to align their interests to overcome the emerging barriers for its full implementation.


Assuntos
Colite Ulcerativa , Doenças Inflamatórias Intestinais , Telemedicina , Humanos , Qualidade de Vida , Doenças Inflamatórias Intestinais/diagnóstico , Doenças Inflamatórias Intestinais/terapia , Computadores de Mão
19.
ACS Appl Mater Interfaces ; 15(51): 59731-59745, 2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38091526

RESUMO

A novel biobased pickering emulsion (PE) material was prepared by the encapsulation of Cyanex 923 (Cy923) into chitosan (CS) to selectively recover rare earth elements (REEs) from the aqueous phase. The preparation of PE was optimized through sequentially applying a 23 full factorial design, followed by a 33 Box-Behnken design varying the Cy923 content, CS concentration, and pH of CS. The material was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), optical microscopy, rheological, compositional, and stability measurements. The resultant material was evaluated in the removal of yttrium by pH influence, nitrate concentration, kinetics, equilibrium isotherms, reusability, and a comparison with liquid-liquid (L-L) extraction and tested in a real scenario to extract Y from a fluorescent lamp powder waste. In addition, the selectivity of PE for REE was investigated with Y/Ca, Gd/Ca, and La/Ni systems. PE extracts REE at 1 ≤ pH ≤ 5 at nitrate concentrations up to 2 mol/L. The kinetics and equilibrium studies showed reaction times <5 min and a maximum sorption capacity of 89.98 mg/g. Compared with L-L extraction, PE consumed 48% less Cy923 without using organic diluents. PE showed a remarkable selectivity for REE in the systems evaluated, showing separation factors of 22.62, 9.35, and 504.64 for the blends Y/Ca, Gd/Ca/Mg, and La/Ni, respectively. PE showed excellent selectivity extracting Y from a real aqueous liquor from the fluorescent lamp powder. PE demonstrates to be an effective and sustainable alternative for REE recovering due to its excellent efficiency in harsh conditions, favorable green chemistry metrics, and use of a biopolymer material in its composition avoiding the use of organic solvents used in L-L extraction.

20.
ACS Sens ; 8(8): 3032-3042, 2023 08 25.
Artigo em Inglês | MEDLINE | ID: mdl-37467113

RESUMO

Health initiatives worldwide demand affordable point-of-care devices to aid in the reduction of morbidity and mortality rates of high-incidence infectious and noncommunicable diseases. However, the production of robust and reliable easy-to-use diagnostic platforms showing the ability to quantitatively measure several biomarkers in physiological fluids and that could in turn be decentralized to reach any relevant environment remains a challenge. Here, we show the particular combination of paper-microfluidic technology, electrochemical transduction, and magnetic nanoparticle-based immunoassay approaches to produce a unique, compact, and easily deployable multiplex device to simultaneously measure interleukin-8, tumor necrosis factor-α, and myeloperoxidase biomarkers in sputum, developed with the aim of facilitating the timely detection of acute exacerbations of chronic obstructive pulmonary disease. The device incorporates an on-chip electrochemical cell array and a multichannel paper component, engineered to be easily aligned into a polymeric cartridge and exchanged if necessary. Calibration curves at clinically relevant biomarker concentration ranges are produced in buffer and artificial sputum. The analysis of sputum samples of healthy individuals and acutely exacerbated patients produces statistically significant biomarker concentration differences between the two studied groups. The device can be mass-produced at a low cost, being an easily adaptable platform for measuring other disease-related target biomarkers.


Assuntos
Microfluídica , Nanopartículas , Humanos , Escarro , Sistemas Automatizados de Assistência Junto ao Leito , Biomarcadores/análise
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