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1.
Int J Mol Sci ; 25(13)2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-39000256

RESUMEN

Biomaterials have demonstrated their ability to serve as effective drug delivery platforms, enabling targeted and localized administration of therapeutic agents [...].


Asunto(s)
Antiinfecciosos , Materiales Biocompatibles , Sistemas de Liberación de Medicamentos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Humanos , Antiinfecciosos/farmacología , Antiinfecciosos/química , Sistemas de Liberación de Medicamentos/métodos , Animales
2.
Mar Drugs ; 21(1)2023 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-36662213

RESUMEN

The brown macroalgae of the species Rugulopteryx okamurae has reached European waters and the Strait of Gibraltar as an invasive species. The proliferation and colonization of the species in subtidal and intertidal zones of these regions imposes significant threats to local ecosystems and additionally represents a significant socioeconomic burden related to the large amounts of biomass accumulated as waste. As a way to minimize the effects caused by the accumulation of algae biomass, investigations have been made to employ this biomass as a raw material in value-added products or technologies. The present review explores the potential uses of R. okamurae, focusing on its impact for biogas production, composting, bioplastic and pharmaceutical purposes, with potential anti-inflammatory, antibacterial and α-glucosity inhibitory activities being highlighted. Overall, this species appears to present many attributes, with remarkable potential for uses in several fields of research and in various industries.


Asunto(s)
Phaeophyceae , Algas Marinas , Ecosistema , Biomasa
3.
Int J Mol Sci ; 24(7)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37047396

RESUMEN

The antibiotic crisis is a global concern [...].


Asunto(s)
Materiales Biocompatibles , Sistemas de Liberación de Medicamentos
4.
Int J Mol Sci ; 23(16)2022 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-36012640

RESUMEN

Biomaterials can be used as implantable devices or drug delivery platforms, which have significant impacts on the patient's quality of life [...].


Asunto(s)
Antiinfecciosos , Materiales Biocompatibles , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Humanos , Prótesis e Implantes , Calidad de Vida
5.
Mar Drugs ; 19(7)2021 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-34201803

RESUMEN

Marine-derived chitosan (CS) is a cationic polysaccharide widely studied for its bioactivity, which is mostly attached to its primary amine groups. CS is able to neutralize reactive oxygen species (ROS) from the microenvironments in which it is integrated, consequently reducing cell-induced oxidative stress. It also acts as a bacterial peripheral layer hindering nutrient intake and interacting with negatively charged outer cellular components, which lead to an increase in the cell permeability or to its lysis. Its biocompatibility, biodegradability, ease of processability (particularly in mild conditions), and chemical versatility has fueled CS study as a valuable matrix component of bioactive small-scaled organic drug-delivery systems, with current research also showcasing CS's potential within tridimensional sponges, hydrogels and sutures, blended films, nanofiber sheets and fabric coatings. On the other hand, renewable plant-derived extracts are here emphasized, given their potential as eco-friendly radical scavengers, microbicidal agents, or alternatives to antibiotics, considering that most of the latter have induced bacterial resistance because of excessive and/or inappropriate use. Loading them into small-scaled particles potentiates a strong and sustained bioactivity, and a controlled release, using lower doses of bioactive compounds. A pH-triggered release, dependent on CS's protonation/deprotonation of its amine groups, has been the most explored stimulus for that control. However, the use of CS derivatives, crosslinking agents, and/or additional stabilization processes is enabling slower release rates, following extract diffusion from the particle matrix, which can find major applicability in fiber-based systems within ROS-enriched microenvironments and/or spiked with microbes. Research on this is still in its infancy. Yet, the few published studies have already revealed that the composition, along with an adequate drug release rate, has an important role in controlling an existing infection, forming new tissue, and successfully closing a wound. A bioactive finishing of textiles has also been promoting high particle infiltration, superior washing durability, and biological response.


Asunto(s)
Antibacterianos/química , Quitosano/química , Extractos Vegetales/química , Antibacterianos/farmacología , Organismos Acuáticos , Sistemas de Liberación de Medicamentos , Nanofibras/química , Nanopartículas/química , Extractos Vegetales/farmacología
6.
Int J Mol Sci ; 22(4)2021 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-33669209

RESUMEN

Nisin Z, an amphipathic peptide, with a significant antibacterial activity against Gram-positive bacteria and low toxicity in humans, has been studied for food preservation applications. Thus far, very little research has been done to explore its potential in biomedicine. Here, we report the modification of sodium alginate (SA) and gelatin (GN) blended microfibers, produced via the wet-spinning technique, with Nisin Z, with the purpose of eradicating Staphylococcus aureus-induced infections. Wet-spun SAGN microfibers were successfully produced at a 70/30% v/v of SA (2 wt%)/GN (1 wt%) polymer ratio by extrusion within a calcium chloride (CaCl2) coagulation bath. Modifications to the biodegradable fibers' chemical stability and structure were then introduced via crosslinking with CaCl2 and glutaraldehyde (SAGNCL). Regardless of the chemical modification employed, all microfibers were labelled as homogeneous both in size (≈246.79 µm) and shape (cylindrical and defect-free). SA-free microfibers, with an increased surface area for peptide immobilization, originated from the action of phosphate buffer saline solution on SAGN fibers, were also produced (GNCL). Their durability in physiological conditions (simulated body fluid) was, however, compromised very early in the experiment (day 1 and 3, with and without Nisin Z, respectively). Only the crosslinked SAGNCL fibers remained intact for the 28 day-testing period. Their thermal resilience in comparison with the unmodified and SA-free fibers was also demonstrated. Nisin Z was functionalized onto the unmodified and chemically altered fibers at an average concentration of 178 µg/mL. Nisin Z did not impact on the fiber's morphology nor on their chemical/thermal stability. However, the peptide improved the SA fibers (control) structural integrity, guaranteeing its stability for longer, in physiological conditions. Its main effect was detected on the time-kill kinetics of the bacteria S. aureus. SAGNCL and GNCL loaded with Nisin Z were capable of progressively eliminating the bacteria, reaching an inhibition superior to 99% after 24 h of culture. The peptide-modified SA and SAGN were not as effective, losing their antimicrobial action after 6 h of incubation. Bacteria elimination was consistent with the release kinetics of Nisin Z from the fibers. In general, data revealed the increased potential and durable effect of Nisin Z (significantly superior to its free, unloaded form) against S. aureus-induced infections, while loaded onto prospective biomedical wet-spun scaffolds.


Asunto(s)
Alginatos/química , Antibacterianos/química , Antibacterianos/farmacología , Reactivos de Enlaces Cruzados/química , Gelatina/química , Nisina/análogos & derivados , Staphylococcus aureus/efectos de los fármacos , Materiales Biocompatibles/química , Plásticos Biodegradables/química , Biopolímeros/química , Cloruro de Calcio/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Glutaral/química , Cinética , Pruebas de Sensibilidad Microbiana , Nisina/química , Nisina/farmacología , Porosidad , Solubilidad , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Agua/química
7.
Int J Geriatr Psychiatry ; 33(8): 1011-1018, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29766579

RESUMEN

OBJECTIVE: Patients with amnestic Mild Cognitive Impairment (aMCI), usually considered an early stage of Alzheimer's disease, have deficits not only in retrospective memory (RM), that is, recalling of past events, words or people, but also on prospective memory (PM), the cognitive ability of remembering to execute delayed intentions in the future. This study investigated whether patients with aMCI refer more PM complaints as compared with RM complaints, and whether this might depend upon short-term vs long-term items or time-based vs event-based tasks. METHODS: Patients with aMCI (n = 178) and healthy controls (n = 160) underwent the Prospective and Retrospective Memory Questionnaire (PRMQ), a 16-item instrument to appraise differences between PM and RM complaints, as well as a general mental state examination, a subjective memory complaints questionnaire, objective memory tests, and assessment of depressive symptoms and activities of daily living. RESULTS: Patients with aMCI reported more memory complaints evaluated with the PRMQ (total score = 44.3 ± 10.8) as compared with controls (36.7 ± 9.8, P < 0.001). Using a mixed effect repeated-measures analysis of covariance (ANCOVA) showed that participants generally referred more retrospective than prospective memory complaints. Patients with aMCI had significantly more complaints on short-term memory as compared with long-term memory, and more complaints in time-based (auto-initiated) as compared with event-based tasks, than healthy controls. CONCLUSION: Patients with aMCI reported significantly more difficulties on short-term memory, presumably reflecting internal temporal lobe pathology typical of Alzheimer's disease, and more complaints on time-based tasks, which are cognitively very demanding, but did not seem particularly troubled regarding prospective memory.


Asunto(s)
Disfunción Cognitiva/psicología , Trastornos de la Memoria/etiología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/psicología , Estudios de Casos y Controles , Depresión/diagnóstico , Femenino , Humanos , Masculino , Memoria Episódica , Memoria a Corto Plazo , Persona de Mediana Edad , Pruebas Neuropsicológicas , Estudios Prospectivos , Estudios Retrospectivos , Encuestas y Cuestionarios
8.
J Neuroophthalmol ; 36(3): 275-9, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27261948

RESUMEN

BACKGROUND: In multiple sclerosis (MS), even in the absence of a clinical episode of optic neuritis (ON), the optic nerve and retinal nerve fiber layer (RNFL) may be damaged leading to dyschromatopsia. Subclinical dyschromatopsia has been described in MS associated with lower motor and cognitive performances. OBJECTIVES: To set the prevalence of dyschromatopsia in eyes of MS patients without a history of ON, to compare its prevalence in patients with and without ON history, and to explore the association between dyschromatopsia and disease duration, average peripapillary RNFL thickness, macular volume, and cognitive and motor performances. METHODS: An observational cross-sectional study was conducted at multiple medical centers. Data were collected after single neurological and ophthalmological evaluations. Dyschromatopsia was defined by the presence of at least 1 error using Hardy-Rand-Rittler plates. RESULTS: In our population of 125 patients, 79 patients (63.2%) never had ON and 35 (28.8%) had unilateral ON. The prevalence of dyschromatopsia in eyes of patients without ON was 25.7%. Patients with dyschromatopsia had a statistically significant lower RNFL thickness (P = 0.004 and P = 0.040, right and left eyes, respectively) and worse performance in symbol digit modalities test (P = 0.012). No differences were found in macular volume or motor function tasks. CONCLUSIONS: Dyschromatopsia occurs frequently in MS patients. It may be associated with a worse disease status and possibly serve as a marker for the detection of subclinical disease progression since it was detected even in the absence of ON. It correlated with thinner peripapillary RNFL thickness and inferior cognitive performance.


Asunto(s)
Defectos de la Visión Cromática/etiología , Visión de Colores/fisiología , Esclerosis Múltiple/complicaciones , Neuritis Óptica/complicaciones , Tomografía de Coherencia Óptica/métodos , Agudeza Visual , Adolescente , Adulto , Defectos de la Visión Cromática/diagnóstico , Defectos de la Visión Cromática/fisiopatología , Estudios Transversales , Progresión de la Enfermedad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/diagnóstico , Fibras Nerviosas/patología , Nervio Óptico/patología , Neuritis Óptica/diagnóstico , Células Ganglionares de la Retina/patología , Adulto Joven
9.
J Mater Sci Mater Med ; 26(11): 261, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26449451

RESUMEN

The research developed on functionalized model or prosthetic surfaces with bioactive polymers has raised the possibility to modulate and/or control the biological in vitro and in vivo responses to synthetic biomaterials. The mechanisms underlying the bioactivity exhibited by sulfonated groups on surfaces involves both selective adsorption and conformational changes of adsorbed proteins. Indeed, surfaces functionalized by grafting poly(sodium styrene sulfonate) [poly(NaSS)] modulate the cellular and bacterial response by inducing specific interactions with fibronectin (Fn). Once implanted, a biomaterial surface is exposed to a milieu of many proteins that compete for the surface which dictates the subsequent biological response. Once understood, this can be controlled by dictating exposure of active binding sites. In this in vitro study, we report the influence of binary mixtures of proteins [albumin (BSA), Fn and collagen type I (Col I)] adsorbed on poly(NaSS) grafted Ti6Al4V on the adhesion and differentiation of MC3T3-E1 osteoblast-like cells and the adhesion and proliferation of Staphylococcus aureus (S. aureus). Outcomes showed that poly(NaSS) stimulated cell spreading, attachment strength, differentiation and mineralization, whatever the nature of protein provided at the interface compared with ungrafted Ti6Al4V (control). While in competition, Fn and Col I were capable of prevailing over BSA. Fn played an important role in the early interactions of the cells with the surface, while Col I was responsible for increased alkaline phosphatase, calcium and phosphate productions associated with differentiation. Poly(NaSS) grafted surfaces decreased the adhesion of S. aureus and the presence of Fn on these chemically altered surfaces increased bacterial resistance ≈70% compared to the ungrafted Ti6Al4V. Overall, our study showed that poly(NaSS) grafted Ti6Al4V selectively adsorbed proteins (particularly Fn) promoting the adhesion and differentiation of osteoblast-like cells while reducing bacterial adhesion to create a bioactive surface with potential for orthopaedic applications.


Asunto(s)
Proteínas Bacterianas/química , Polímeros/química , Staphylococcus aureus/fisiología , Titanio/química , Células 3T3 , Animales , Adhesión Bacteriana , Diferenciación Celular , Proliferación Celular , Ratones , Unión Proteica , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie
10.
Langmuir ; 30(31): 9477-83, 2014 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-25054428

RESUMEN

Functionalization of surfaces with poly(sodium styrenesulfonate) (poly(NaSS)) has recently been found to enhance osteointegration of implantable materials. Radical polymerization of poly(NaSS) on titanium (Ti)-based substrates has been used to improve their long-term performance by preventing fibrosis and consequently implant loosening. However, the influence of the sulfonate groups on the early cell behavior and the associated molecular phenomena remains to be understood. In this work, we used quartz crystal microbalance with dissipation (QCM-D) to elucidate the role of poly(NaSS) in enhancing osteoblastic cell attachment. This was measured by following the cell attachment using the MC3T3-E1 cell line, on fetal bovine serum (FBS) preadsorbed surfaces and on substrates adsorbed with a series of relevant proteins, bovine serum albumin (BSA), fibronectin (Fn), and collagen type I (Col I). Comparison of the performance of poly(NaSS) with other clinically important substrates such as Ti alloy Ti6Al4V, gold, and poly(desamino-tyrosyl-tyrosine ethyl ester carbonate) (poly(DTEc)) indicates poly(NaSS) to be a superior substrate for MC3T3-E1 cells attachment. This attachment was found to be integrin mediated in the presence of Fn and Col I. Antibodies specific to the RGD peptide and the N- and C-terminal HB-binding domains reacted more intensively with Fn adsorbed on poly(NaSS). Fn adapts a conformation favorable to RGD mediated cell attachment when adsorbed onto poly(NaSS).


Asunto(s)
Colágeno Tipo I/química , Fibronectinas/química , Osteoblastos/citología , Poliestirenos/química , Células 3T3 , Aluminio/química , Animales , Biopolímeros/química , Oro/química , Ratones , Conformación Molecular , Tamaño de la Partícula , Tecnicas de Microbalanza del Cristal de Cuarzo , Albúmina Sérica Bovina/química , Propiedades de Superficie , Titanio/química , Tirosina/análogos & derivados , Tirosina/química , Vanadio/química
11.
J Stroke Cerebrovasc Dis ; 23(6): 1416-20, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24560245

RESUMEN

BACKGROUND: Nowadays, the number of patients undergoing carotid artery stenting (CAS) is increasing rapidly, and these patients require follow-up to monitor the patency of the device and the potential development of an in-stent restenosis (ISR). METHODS: Patients undergoing CAS at our institution underwent duplex ultrasound (DUS) at 6 months, 12 months, and yearly thereafter, using a prespecified protocol. Restenosis was defined as a more than 50% diameter-reducing stenosis. Patients with DUS-diagnosed restenosis underwent carotid computerized tomography angiography (CTA) to confirm the presence of ISR. The frequency of restenosis was calculated by Kaplan-Meier survival estimates and was compared during a 2-year follow-up period. Interactions between restenosis and baseline variables were assessed using odds ratio. RESULTS: Between August 2007 and March 2012 were performed 100 procedures in 96 patients, with a median age of 72.9 years. The mean duration of follow-up was 29.2 months (±8.4). Restenosis occurred in 6 carotid arteries. The Kaplan-Meier estimate for the frequency of restenosis in 2 years was 6.0% and for severe restenosis was 3.0%. There were no occlusions. Diabetic patients seem to have a higher risk of ISR (OR=3.23, 95% CI .55-18.9). Carotid CTA was in agreement with the degree of stenosis estimated by DUS in all cases. CONCLUSIONS: Our results, using a DUS protocol and a specific peak systolic velocity threshold, showed that the frequency of restenosis at 2 years after CAS is 6.0% and so that CAS is probably a durable revascularization procedure. We emphasize the diagnostic agreement achieved between DUS and carotid CTA.


Asunto(s)
Arteria Carótida Común/cirugía , Estenosis Carotídea/cirugía , Endarterectomía Carotidea/métodos , Stents , Anciano , Anciano de 80 o más Años , Arteria Carótida Común/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Ultrasonografía
12.
Int J Biol Macromol ; 277(Pt 4): 134565, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39116984

RESUMEN

Chronic wounds represent a serious worldwide concern, being often associated with bacterial infections. As the prevalence of bacterial infections increase, it is crucial to search for alternatives. Essential oils (EOs) constitute a promising option to antibiotics due to their strong anti-inflammatory, analgesic, antioxidant and antibacterial properties. However, such compounds present high volatility. To address this issue, a drug delivery system composed of coaxial wet-spun fibers was engineered and different EOs, namely clove oil (CO), cinnamon leaf oil (CLO) and tea tree oil (TTO), were loaded. Briefly, a coaxial system composed of two syringe pumps, a coagulation bath of deionized water, a cylindrical-shaped collector and a coaxial spinneret was used. A 10 % w/v polycaprolactone (PCL) solution was combined with the different EOs at 2 × minimum bactericidal concentration (MBC) and loaded to a syringe connected to the inner port, whereas a 10 % w/v cellulose acetate (CA) solution mixed with 10 % w/v polyethylene glycol (PEG) at a ratio of 90:10 % v/v (to increase the fibers' elasticity) was loaded to the syringe connected to the outer port. This layer was used as a barrier to pace the release of the entrapped EO. The CA's inherent porosity in water coagulation baths allowed access to the fiber's core. CA was also mixed with 10 % w/v polyethylene glycol (PEG) at a ratio of 90:10 % v/v (CA:PEG), to increase the fibers' elasticity. Microfibers maintained their structural integrity during 28 days of incubation in physiological-like environments. They also showed high elasticities (maximum elongations at break >300 %) and resistance to rupture in mechanical assessments, reaching mass losses of only ≈ 2.29 % - 57.19 %. The EOs were released from the fibers in a prolonged and sustained fashion, in which ≈ 30 % of EO was released during the 24 h of incubation in physiological-like media, demonstrating great antibacterial effectiveness against Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli and Pseudomonas aeruginosa, the most prevalent bacteria in chronic wounds. Moreover, microfibers showed effective antioxidant effects, presenting up to 59 % of reduction of 2,2-diphenyl-1-picrylhydrazyl (DPPH) activity. Furthermore, the coaxial system was deemed safe for contact with fibroblasts and human keratinocytes, reaching metabolic activities higher than 80 % after 48 h of incubation. Data confirmed the suitability of the engineered system for potential therapeutics of chronic wounds.


Asunto(s)
Antioxidantes , Celulosa , Aceites Volátiles , Poliésteres , Poliésteres/química , Antioxidantes/farmacología , Antioxidantes/química , Aceites Volátiles/farmacología , Aceites Volátiles/química , Celulosa/química , Celulosa/análogos & derivados , Celulosa/farmacología , Antiinfecciosos/farmacología , Antiinfecciosos/química , Antibacterianos/farmacología , Antibacterianos/química , Humanos , Cicatrización de Heridas/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos
13.
Biomater Adv ; 162: 213931, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38924805

RESUMEN

Microbial colonization and development of infections in wounds is a sign of chronicity. The prevailing approach to manage and treat these wounds involves dressings. However, these often fail in effectively addressing infections, as they struggle to both absorb exudates and maintain optimal local moisture. The system here presented was conceptualized with a three-layer design: the outer layer made of a fibrous polycaprolactone (PCL) film, to act as a barrier for preventing microorganisms and impurities from reaching the wound; the intermediate layer formed of a sodium alginate (SA) hydrogel loaded with ampicillin (Amp) for fighting infections; and the inner layer comprised of a fibrous film of PCL and polyethylene glycol (PEG) for facilitating cell recognition and preventing wound adhesion. Thermal evaluations, degradation, wettability and release behavior testing confirmed the system resistance overtime. The sandwich demonstrated the capability for absorbing exudates (≈70 %) and exhibited a controlled release of Amp for up to 24 h. Antimicrobial testing was performed against Staphylococcus aureus and Escherichia coli, as representatives of Gram-positive and Gram-negative bacteria: >99 % elimination of bacteria. Cell cytotoxicity assessments showed high cytocompatibility levels, confirming the safety of the proposed sandwich system. Adhesion assays confirmed the system ease of detaching without mechanical effort (0.37 N). Data established the efficiency of the sandwich-like system, suggesting promising applications in infected wound care.


Asunto(s)
Alginatos , Antibacterianos , Escherichia coli , Poliésteres , Staphylococcus aureus , Infección de Heridas , Alginatos/química , Infección de Heridas/tratamiento farmacológico , Infección de Heridas/microbiología , Staphylococcus aureus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antibacterianos/química , Antibacterianos/administración & dosificación , Poliésteres/química , Ampicilina/farmacología , Ampicilina/uso terapéutico , Ampicilina/química , Humanos , Hidrogeles/química , Polietilenglicoles/química , Animales , Vendajes , Pruebas de Sensibilidad Microbiana , Ratones , Cicatrización de Heridas/efectos de los fármacos
14.
Pharmaceutics ; 16(7)2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-39065608

RESUMEN

In diabetic ulcers, an increased secretion of human neutrophil elastase (HNE) and bacterial infections play crucial roles in hindering healing. Considering that, the present study proposed the development of multi-action polycaprolactone (PCL)/polyethylene glycol (PEG) electrospun fibers incorporating elastase-targeting peptides, AAPV and WAAPV, via blending. Characterization confirmed WAAPV's efficacy in regulating proteolytic enzymes by inhibiting HNE. The engineered fibers, particularly those containing PEG, exhibited optimal wettability but an accelerated degradation that was mitigated with the peptide's inclusion, thus promoting a sustained peptide release over 24 h. Peptide loading was verified indirectly through thermal stability and hydration capacity studies (hydrophobic bonding between PCL and WAAPV and hydrophilic affinities between PCL/PEG and AAPV) and determined at ≈51.1 µg/cm2 and ≈46.0 µg/cm2 for AAPV and ≈48.5 µg/cm2 and ≈51.3 µg/cm2 for WAAPV, respectively, for PCL and PCL/PEG. Both AAPV and WAAPV effectively inhibited HNE, with PEG potentially enhancing this effect by interacting with the peptides and generating detectable peptide-PEG complexes (≈10% inhibition with PCL + peptide fibers after 6 h of incubation, and ≈20% with PCL/PEG + peptide fibers after 4 h incubation). Peptide-loaded fibers demonstrated antibacterial efficacy against Staphylococcus aureus (up to ≈78% inhibition) and Escherichia coli (up to ≈66% inhibition), with peak effectiveness observed after 4 and 2 h of incubation, respectively. This study provides initial insights into the WAAPV's potential for inhibiting HNE and bacteria activities, showing promise for applications in diabetic ulcer management.

15.
J Neurol Sci ; 464: 123176, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-39146881

RESUMEN

INTRODUCTION: Neuromyelitis optica spectrum disorders (NMOSD) and MOG-associated disease (MOGAD) are an increasingly recognized group of demyelinating disorders of the central nervous system. Previous studies suggest that prognosis is predicted by older age at onset, number of relapses, the severity of the first attack and autoantibody status. OBJECTIVE: To study prognostic factors associated with disability progression and additional relapses in the 3-year follow-up of a national NMOSD/MOGAD cohort. RESULTS: Out of 180 of the initial Portuguese cohort, data on 82 patients was available at the end of the follow-up period (2019-2022). Two patients died. Twenty (24.4%) patients had one or more attack in this period (25 attacks in total), mostly transverse myelitis (TM) (56.0%) or optic neuritis (32.0%). MOGAD was significantly associated with a monophasic disease course (p = 0.03), with milder attacks (p = 0.01), while AQP4 + NMOSD was associated with relapses (p = 0.03). The most common treatment modalities were azathioprine (38.8%) and rituximab (18.8%). AQP4 + NMOSD more frequently required chronic immunosuppressive treatment, particularly rituximab (p = 0.01). Eighteen (22.5%) had an EDSS ≥6 at the end of the follow-up. AQP4 + NMOSD (p < 0.01) and the occurrence of transverse myelitis (TM) during disease (p = 0.04) correlated with an EDSS≥6 at the end of the follow-up period. MOGAD was significantly associated with an EDSS<6 (p < 0.01), and MOG+ cases that reached an EDSS>6 were significantly older (64.0 ± 2.8 versus 31.0 ± 17.1, p = 0.017). A bivariate logistic regression model including the serostatus and TM attacks during disease history successfully predicted 72.2% of patients that progressed to an EDSS≥6. CONCLUSION: This study highlights that myelitis predict increased disability (EDSS≥6) in NMOSD/MOGAG and AQP4 positivity is associated with increased disability.


Asunto(s)
Glicoproteína Mielina-Oligodendrócito , Neuromielitis Óptica , Sistema de Registros , Humanos , Neuromielitis Óptica/epidemiología , Femenino , Masculino , Portugal/epidemiología , Adulto , Pronóstico , Persona de Mediana Edad , Glicoproteína Mielina-Oligodendrócito/inmunología , Estudios de Cohortes , Progresión de la Enfermedad , Autoanticuerpos/sangre , Personas con Discapacidad , Evaluación de la Discapacidad , Acuaporina 4/inmunología , Adulto Joven , Estudios de Seguimiento , Anciano , Recurrencia
16.
Antibiotics (Basel) ; 12(7)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37508223

RESUMEN

In the last couple of years, the awareness of climate change and high pollution levels have raised our sense of ecological responsibility [...].

17.
Pharmaceutics ; 15(1)2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36678887

RESUMEN

Diabetic foot ulcers (DFUs) are one of the main complications of diabetes and are characterized by their complexity and severity, which are frequently aggravated by overexpressed inflammatory factors and polymicrobial infections. Most dressing systems offer a passive action in the treatment of DFUs, being frequently combined with antibiotic or immunomodulatory therapies. However, in many instances due to these combined therapies' inability to properly fight microbial presence, and provide a suitable, breathable and moist environment that is also capable of protecting the site from secondary microbial invasions or further harm, aggravation of the wound state is unavoidable and lower limb amputations are necessary. Considering these limitations and knowing of the urgent demand for new and more effective therapeutic systems for DFU care that will guarantee the quality of life for patients, research in this field has boomed in the last few years. In this review, the emerging innovations in DFU dressing systems via fiber-based scaffolds modified with bioactive compounds have been compiled; data focused on the innovations introduced in the last five years (2017-2022). A generalized overview of the classifications and constraints associated with DFUs healing and the bioactive agents, both antimicrobial and immunomodulatory, that can contribute actively to surpass such issues, has also been provided.

18.
Biomedicines ; 11(7)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37509502

RESUMEN

The potential of nanoparticles as effective drug delivery systems combined with the versatility of fibers has led to the development of new and improved strategies to help in the diagnosis and treatment of diseases. Nanoparticles have extraordinary characteristics that are helpful in several applications, including wound dressings, microbial balance approaches, tissue regeneration, and cancer treatment. Owing to their large surface area, tailor-ability, and persistent diameter, fibers are also used for wound dressings, tissue engineering, controlled drug delivery, and protective clothing. The combination of nanoparticles with fibers has the power to generate delivery systems that have enhanced performance over the individual architectures. This review aims at illustrating the main possibilities and trends of fibers functionalized with nanoparticles, focusing on inorganic and organic nanoparticles and polymer-based fibers. Emphasis on the recent progress in the fabrication procedures of several types of nanoparticles and in the description of the most used polymers to produce fibers has been undertaken, along with the bioactivity of such alliances in several biomedical applications. To finish, future perspectives of nanoparticles incorporated within polymer-based fibers for clinical use are presented and discussed, thus showcasing relevant paths to follow for enhanced success in the field.

19.
Biomater Adv ; 151: 213488, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37285725

RESUMEN

In chronic wound (CW) scenarios, Staphylococcus aureus-induced infections are very prevalent. This leads to abnormal inflammatory processes, in which proteolytic enzymes, such as human neutrophil elastase (HNE), become highly expressed. Alanine-Alanine-Proline-Valine (AAPV) is an antimicrobial tetrapeptide capable of suppressing the HNE activity, restoring its expression to standard rates. Here, we proposed the incorporation of the peptide AAPV within an innovative co-axial drug delivery system, in which the peptide liberation was controlled by N-carboxymethyl chitosan (NCMC) solubilization, a pH-sensitive antimicrobial polymer effective against Staphylococcus aureus. The microfibers' core was composed of polycaprolactone (PCL), a mechanically resilient polymer, and AAPV, while the shell was made of the highly hydrated and absorbent sodium alginate (SA) and NCMC, responsive to neutral-basic pH (characteristic of CW). NCMC was loaded at twice its minimum bactericidal concentration (6.144 mg/mL) against S. aureus, while AAPV was loaded at its maximum inhibitory concentration against HNE (50 µg/mL), and the production of fibers with a core-shell structure, in which all components could be detected (directly or indirectly), was confirmed. Core-shell fibers were characterized as flexible and mechanically resilient, and structurally stable after 28-days of immersion in physiological-like environments. Time-kill kinetics evaluations revealed the effective action of NCMC against S. aureus, while elastase inhibitory activity examinations proved the ability of AAPV to reduce HNE levels. Cell biology testing confirmed the safety of the engineered fiber system for human tissue contact, with fibroblast-like cells and human keratinocytes maintaining their morphology while in contact with the produced fibers. Data confirmed the engineered drug delivery platform as potentially effective for applications in CW care.


Asunto(s)
Quitosano , Infecciones Estafilocócicas , Humanos , Alginatos/farmacología , Quitosano/farmacología , Quitosano/química , Elastasa de Leucocito/metabolismo , Elastasa de Leucocito/farmacología , Péptidos/farmacología , Polímeros/farmacología , Staphylococcus aureus/metabolismo , Valina/farmacología , Heridas y Lesiones/complicaciones , Heridas y Lesiones/microbiología , Heridas y Lesiones/terapia , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología
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