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2.
J Environ Manage ; 363: 121363, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38850911

RESUMEN

The footwear industry significantly impacts the environment, from raw material extraction to waste disposal. Transforming waste into new products is a viable option to mitigate the environmental consequences, reducing the reliance on virgin raw materials. This work aims to develop thermal and acoustic insulation materials using polyester waste from footwear industry. Two nonwoven and two compressed nonwoven structures, comprising 80% polyester waste and 20% commercial recycled polyester (matrix), were produced. The materials were created through needle-punching and compression molding techniques. The study included the production of sandwich and monolayer nonwoven structures, which were evaluated considering area weight, thickness, air permeability, mechanical properties, morphology using field emission scanning electron microscopy, and thermal and acoustic properties. The nonwoven samples presented high tensile strength (893 kPa and 629 kPa) and the highest strain (79.7% and 73.3%) and compressed nonwoven structures showed higher tensile strength (2700 kPa and 1291 kPa) but reduced strain (25.8% and 40.8%). Nonwoven samples showed thermal conductivity of 0.041 W/K.m and 0.037 W/K.m. Compressed nonwoven samples had higher values at 0.060 W/K.m and 0.070 W/K.m. While the sample with the highest conductivity exceeds typical insulation levels, other samples are suitable for thermal insulation. Nonwoven structures exhibited good absorption coefficients (0.640-0.644), suitable for acoustic insulation. Compressed nonwoven structures had lower values (0.291-0.536), unsuitable for this purpose. In summary, this study underscores the potential of 100% recycled polyester structures derived from footwear and textile industry waste, showcasing remarkable acoustic and thermal insulation properties ideal for the construction sector.


Asunto(s)
Acústica , Zapatos , Resistencia a la Tracción , Poliésteres/química , Reciclaje
3.
ACS Appl Mater Interfaces ; 16(13): 16861-16879, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38507790

RESUMEN

The endotracheal tube (ETT) affords support for intubated patients, but the increasing incidence of ventilator-associated pneumonia (VAP) is jeopardizing its application. ETT surfaces promote (poly)microbial colonization and biofilm formation, with a heavy burden for VAP. Devising safe, broad-spectrum antimicrobial materials to tackle the ETT bioburden is needful. Herein, we immobilized ciprofloxacin (CIP) and/or chlorhexidine (CHX), through polydopamine (pDA)-based functionalization, onto poly(vinyl chloride) (PVC) surfaces. These surfaces were characterized regarding physicochemical properties and challenged with single and polymicrobial cultures of VAP-relevant bacteria (Pseudomonas aeruginosa, Acinetobacter baumannii, Klebsiella pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis) and fungi (Candida albicans). The coatings imparted PVC surfaces with a homogeneous morphology, varied wettability, and low roughness. The antimicrobial immobilization via pDA chemistry was still evidenced by infrared spectroscopy. Coated surfaces exhibited sustained CIP/CHX release, retaining prolonged (10 days) activity. CIP/CHX-coated surfaces evidencing no A549 lung cell toxicity displayed better antibiofilm outcomes than CIP or CHX coatings, preventing bacterial attachment by 4.1-7.2 Log10 CFU/mL and modestly distressingC. albicans. Their antibiofilm effectiveness was endured toward polymicrobial consortia, substantially inhibiting the adhesion of the bacterial populations (up to 8 Log10 CFU/mL) within the consortia in dual- and even inP. aeruginosa/S. aureus/C. albicans triple-species biofilms while affecting fungal adhesion by 2.7 Log10 CFU/mL (dual consortia) and 1 Log10 CFU/mL (triple consortia). The potential of the dual-drug coating strategy in preventing triple-species adhesion and impairing bacterial viability was still strengthened by live/dead microscopy. The pDA-assisted CIP/CHX co-immobilization holds a safe and robust broad-spectrum antimicrobial coating strategy for PVC-ETTs, with the promise laying in reducing VAP incidence.


Asunto(s)
Antiinfecciosos , Neumonía Asociada al Ventilador , Cloruro de Vinilo , Humanos , Clorhexidina/farmacología , Ciprofloxacina , Staphylococcus aureus , Antiinfecciosos/farmacología , Intubación Intratraqueal , Neumonía Asociada al Ventilador/microbiología , Neumonía Asociada al Ventilador/prevención & control , Bacterias , Biopelículas , Pseudomonas aeruginosa
4.
Artículo en Inglés | MEDLINE | ID: mdl-38111112

RESUMEN

INTRODUCTION: Single Nucleotide Polymorphisms (SNPs) are used as drug susceptibility biomarkers in metabolic diseases. Alterations in the gene encoding triggers the enzyme flavin monooxygenase 3 (FMO3), involved in the Sulindac metabolization, which also is responsible for the inherited metabolic disorder. Trimethylaminuria (TMAu, OMIM: 602079). DPYD gene variants are associated with the enzyme dihydropyrimidine dehydrogenase deficiency (DPD; OMIM: 274270). This autosomal recessive metabolic disorder, ultimately leads to the inability to metabolize fluoropyrimidines, which causes severe toxicity in individuals treated with these drugs. METHODS: Variants in genes responsible for the expression of enzymes that encode transporters or receptors involved in the metabolization pathways of certain drugs may condition the individuals response to certain drugs, compromising the therapeutic response and clinical prognosis. Thus the sequencing and identification of variants become relevant, not only gain knowledge on effects of these variants' on disease causality but also in terms of its side effects resulting from the coding enzymes responsible for drug metabolization. RESULTS: It was found that patients with the c.472G>A (p.Glu158Lys) and c.923A>G (p.Glu308Gly) polymorphisms, in homozygosity, in FMO3 gene did not develop polyps, thus have a protective effect in the treatment of Familial Adenomatous Polyposis (PAF). However, in the case of the DPYD gene, c.1905+1G>A (IVS14+1G>A), c.1679T>G (p.Ile560Ser), c.2846A>T (p.Asp949Val) e c.1236G>A/HapB3 variants can be lethal in cancer patients indicated for fluoropyrimidine-based chemotherapy. CONCLUSION: Knowledge on the drug mechanisms will affect the therapeutic response of patients treated with a given drug. Thus, pharmacogenetics is an essential tool in personalized medicine, since molecular studies allows the clinician to predict the probability of efficacy and toxicity of certain drugs, resulting higher efficiency in individualizing treatment and also improving the safety of the patient. From a personalized medicine perspective, the study of the characteristics of the drug and its metabolization site, the genes involved in the encoding of enzymes responsible for its metabolization will be of great interest.

5.
Molecules ; 28(7)2023 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-37049815

RESUMEN

Cancer remains one of the most challenging health problems worldwide, and localized therapeutic approaches based on micro/nanofibers have shown potential for its treatment. Micro/nanofibers offer several advantages as a drug delivery system, such as high surface area, tunable pore size, and sustained release properties, which can improve drug efficacy and reduce side effects. In addition, functionalization of these fibers with nanoparticles can enhance their targeting and therapeutic capabilities. Localized delivery of drugs and/or other therapeutic agents via micro/nanofibers can also help to overcome the limitations of systemic administration, such as poor bioavailability and off-target effects. Several studies have shown promising results in preclinical models of cancer, including inhibition of tumor growth and improved survival rates. However, more research is needed to overcome technical and regulatory challenges to bring these approaches to clinical use. Localized therapeutic approaches based on micro/nanofibers hold great promise for the future of cancer treatment, providing a targeted, effective, and minimally invasive alternative to traditional treatments. The main focus of this review is to explore the current treatments utilizing micro/nanofibers, as well as localized drug delivery systems that rely on fibrous structures to deliver and release drugs for the treatment of cancer in a specific area.


Asunto(s)
Nanofibras , Neoplasias , Humanos , Nanofibras/uso terapéutico , Nanofibras/química , Sistemas de Liberación de Medicamentos , Neoplasias/tratamiento farmacológico
6.
Analyst ; 148(7): 1595-1602, 2023 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-36897283

RESUMEN

Oxidative treatment of human red blood cells (RBCs) prior to freeze-drying appears to stabilize the RBCs to withstand dried storage at room temperature. To better understand the effects of oxidation and freeze-drying/rehydration on RBC lipids and proteins, single-cell measurements were performed by synchrotron-based Fourier transform infrared (FTIR) microspectroscopy 'live-cell' (unfixed) analysis. Lipid and protein spectral data of tert-butyl hydroperoxide (TBHP)-oxidized RBCs (oxRBCs), FDoxRBCs and control (untreated) RBCs were compared using principal component analysis (PCA) and band integration ratios. The oxRBCs and FDoxRBCs samples had similar spectral profiles that were clearly different to control RBCs. Spectral changes in the CH stretching region of oxRBCs and FDoxRBCs indicated the presence of increased saturated and shorter-chain lipids, consistent with lipid peroxidation and stiffening of the RBC membrane compared to control RBCs. The PCA loadings plot for the fingerprint region of control RBCs corresponding to the α-helical structure of hemoglobin, shows that oxRBCs and FDoxRBCs have conformational changes in the protein secondary structure to ß-pleated sheets and ß-turns. Finally, the freeze-drying process did not appear to compound or induce additional changes. In this context, FDoxRBCs could become a stable source of reagent RBCs for pre-transfusion blood serology testing. The synchrotron FTIR microspectroscopic live-cell protocol provides a powerful analytical tool to characterize and contrast the effects of different treatments on RBC chemical composition at the single cell level.


Asunto(s)
Eritrocitos , Sincrotrones , Humanos , Espectroscopía Infrarroja por Transformada de Fourier/métodos , Análisis de Fourier , Lípidos/química
7.
Children (Basel) ; 10(2)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36832435

RESUMEN

It is important to identify children who are struggling with emergent literacy skills as early as possible to provide them with the support they need to prevent future academic failure. Screening tools administered in groups are more cost-effective than those administered individually, but few are available in Portugal. The goal of this study was to explore the psychometric properties (difficulty, reliability, and validity) of a group emergent literacy screening test for Portuguese-speaking children. The test includes two phonological awareness tasks, one vocabulary task, and one concepts of print task. The sample comprised 1379 children from pre-K (n = 314), kindergarten (n = 579), and first grade of primary education (n = 486). Measures of emergent literacy, reading and writing skills, and academic achievement were used to test the validity of the screening test. The Rasch model results suggest that the tasks were suitably difficult for the kindergarten group, but had varying levels of difficulty for pre-K and first grade. Reliability was adequate for the tasks with an appropriate level of difficulty. Scores for the screening test were highly correlated with measures of literacy and with academic achievement. These findings suggest that the presented emergent literacy screening test is valid and reliable, making it a useful tool for practice and research.

8.
Acta Biomater ; 158: 32-55, 2023 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-36632877

RESUMEN

Ventilator-associated pneumonia (VAP) is an unresolved problem in nosocomial settings, remaining consistently associated with a lack of treatment, high mortality, and prolonged hospital stay. The endotracheal tube (ETT) is the major culprit for VAP development owing to its early surface microbial colonization and biofilm formation by multiple pathogens, both critical events for VAP pathogenesis and relapses. To combat this matter, gradual research on antimicrobial ETT surface coating/modification approaches has been made. This review provides an overview of the relevance and implications of the ETT bioburden for VAP pathogenesis and how technological research on antimicrobial materials for ETTs has evolved. Firstly, certain main VAP attributes (definition/categorization; outcomes; economic impact) were outlined, highlighting the issues in defining/diagnosing VAP that often difficult VAP early- and late-onset differentiation, and that generate misinterpretations in VAP surveillance and discrepant outcomes. The central role of the ETT microbial colonization and subsequent biofilm formation as fundamental contributors to VAP pathogenesis was then underscored, in parallel with the uncovering of the polymicrobial ecosystem of VAP-related infections. Secondly, the latest technological developments (reported since 2002) on materials able to endow the ETT surface with active antimicrobial and/or passive antifouling properties were annotated, being further subject to critical scrutiny concerning their potentialities and/or constraints in reducing ETT bioburden and the risk of VAP while retaining/improving the safety of use. Taking those gaps/challenges into consideration, we discussed potential avenues that may assist upcoming advances in the field to tackle VAP rampant rates and improve patient care. STATEMENT OF SIGNIFICANCE: The use of the endotracheal tube (ETT) in patients requiring mechanical ventilation is associated with the development of ventilator-associated pneumonia (VAP). Its rapid surface colonization and biofilm formation are critical events for VAP pathogenesis and relapses. This review provides a comprehensive overview on the relevance/implications of the ETT biofilm in VAP, and on how research on antimicrobial ETT surface coating/modification technology has evolved over the last two decades. Despite significant technological advances, the limited number of gathered reports (46), highlights difficulty in overcoming certain hurdles associated with VAP (e.g., persistent colonization/biofilm formation; mechanical ventilation duration; hospital length of stay; VAP occurrence), which makes this an evolving, complex, and challenging matter. Challenges and opportunities in the field are discussed.


Asunto(s)
Antiinfecciosos , Neumonía Asociada al Ventilador , Humanos , Ecosistema , Intubación Intratraqueal/efectos adversos , Antiinfecciosos/farmacología , Antiinfecciosos/uso terapéutico , Biopelículas
9.
Chirurgia (Bucur) ; 117(5): 535-543, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36318683

RESUMEN

Background: Colonoscopy is currently the gold-standard for the detection of colorectal lesions, but its accuracy in tumor localization is limited. This study aims to determine the accuracy of colonoscopy in localization of colorectal malignancy, identify possible influencing factors and evaluate the surgical consequences of an incorrect preoperative localization. Methods: A retrospective cross-sectional study of all patients with colorectal malignant lesions diagnosed by colonoscopy who underwent subsequent resection surgery between January 2019 and December 2020 was performed. Colonoscopy accuracy was evaluated in terms of correspondence between endoscopic and intra-operative tumor localization. Results: A total of 115 patients were included, mostly males (63.5%), with mean age of 68.7 years. There was concordance between endoscopic and intra-operative localization in 76 cases, which corresponds to an accuracy of 66.1%. Colonoscopy completeness (p=0.008) and adequate bowel preparation (p=0.023) were significantly associated with greater concordance between endoscopic and intra-operative tumor location. Of the 39 incorrectly localized lesions, 19 (48.7%) required changes in surgical management. Conclusion: Colonoscopy is often inaccurate for localizing malignant colorectal lesions, which may frequently result in intra-operative changes in surgical strategy. Colonoscopy completeness and adequate bowel preparation were significant predictors for a correct endoscopic localization, underscoring the importance of colonoscopy quality for this particular indication.


Asunto(s)
Colonoscopía , Neoplasias Colorrectales , Masculino , Humanos , Anciano , Femenino , Estudios Retrospectivos , Estudios Transversales , Resultado del Tratamiento , Neoplasias Colorrectales/cirugía
10.
Vox Sang ; 117(11): 1302-1309, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36102143

RESUMEN

BACKGROUND AND OBJECTIVES: Pre-transfusion antibody screening requires the detection and identification of immunoglobulin G (IgG) antibodies against red blood cells (RBCs). Using the indirect antiglobulin test (IAT), plasma-RBC solutions are incubated at 37°C in gel cards, typically by heating block technology. Here, we apply the newly developed laser incubation method to detect RBC alloantibodies in the plasma from human donors. MATERIALS AND METHODS: Donated human plasma samples (N = 128) containing clinically significant IgG antibodies directed against Rh (D, C, c, Cw and E), Kell (K and Kpa ), Duffy (Fya and Fyb ), Kidd (Jka ) and MNS (S) blood group system antigens were tested by the indirect antiglobulin test (IAT). Samples were heated to 37°C by infrared laser (980 nm) for incubations of up to 5 min. Samples were also incubated in a heating block for comparison. RESULTS: When heating by laser, the presence of an alloantibody is detected after only a 1-min incubation for 96% of samples. No samples required longer than 3 min of laser incubation in order to detect the antibody. For all samples, incubation by laser gave the same or stronger result within 5 min. No samples required longer than 5 min to achieve an equivalent result to that of the 5-min heating block incubation. The laser was not found to damage cells or antibodies. CONCLUSION: Laser incubation provides comparable results in shorter time frames than the heating block. Laser incubation can rapidly detect even very weak antibodies.


Asunto(s)
Antígenos de Grupos Sanguíneos , Isoanticuerpos , Humanos , Prueba de Coombs/métodos , Eritrocitos , Inmunoglobulina G
11.
Front Psychol ; 13: 963367, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35959030

RESUMEN

The COVID-19 pandemic challenged countries, regions, schools, and individuals. School closures due to lockdowns forced changes in the teaching practices and the learning support provided to children at home. This study aimed to provide insights on the changes between the first and the second lockdowns in Portugal, concerning remote teaching practices and family support to children's education. A self-report questionnaire was filled by 144 parents of third grade students. The results show that, between the two lockdowns, there was a significant decrease in the amount of support provided at home to school assignments and activities, as well as in the amount of time spent by students in TV broadcasted lessons and in reading training supported by the family. Inversely, families reported a significant increase in the amount of time spent by students in independent reading activities and in the time spent in training reading guided by teachers. The number of synchronous lessons with a teacher and the number of times students trained reading during a synchronous lesson also increased in the second lockdown. Additionally, in the second lockdown, parents perceived synchronous lessons to be more effective at improving their child's reading skills and perceived themselves as more capable of supporting their child in reading acquisition. These findings are used to discuss school responses and remote teaching and learning practices during the COVID-19 pandemic.

12.
Biofouling ; 38(6): 547-557, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35903005

RESUMEN

Biofilm formation on endotracheal tubes (ETT) is an important factor in the development of ventilator-associated pneumonia (VAP). This work aimed to investigate the effectiveness of colistin (COL) against the early stages of biofilm formation by Pseudomonas aeruginosa. Two strategies were used: pre-conditioning the adhesion surfaces with COL before biofilm formation and growing biofilms in its presence. The combined effect of treating P. aeruginosa 24-hours old biofilms with Ciprofloxacin (CIP) or colistin (COL) on clean and COL-conditioned surfaces was also assessed. Random deposition of COL residues altered the physico-chemical properties of the adhesion surfaces and impaired biofilm formation. Moreover, as a consequence of the reduced amount of biofilms attached to COL conditioned surfaces, adhered cells became more exposed to the subsequent action of CIP or COL, suggesting a combined outcome of prophylactic and therapeutic COL-based strategies. Results highlighted the promising use of COL to prevent the establishment of biofilms on ETT.


Asunto(s)
Antiinfecciosos , Infecciones por Pseudomonas , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Antiinfecciosos/farmacología , Biopelículas , Ciprofloxacina/farmacología , Colistina/farmacología , Colistina/uso terapéutico , Humanos , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa , Ventiladores Mecánicos
13.
Plants (Basel) ; 10(12)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34961170

RESUMEN

Invasive species are currently a world menace to the environment, although the study of their chemistry may provide a means for their future beneficial use. From a study of Portuguese Acacia melanoxylon R. Br. five known compounds were isolated: lupeol, 3ß-Z-coumaroyl lupeol, 3ß-E-coumaroyl lupeol (dioslupecin A), kolavic acid 15-methyl ester and vomifoliol (blumenol A). Their structures were elucidated by 1D and 2D NMR spectroscopy and mass spectrometry, and as a result some corrections are made to their previous 13C NMR assignments. Cytotoxicity of 3ß-E-coumaroyl lupeol (dioslupecin A) and kolavic acid 15-methyl ester was evaluated against HCT116 human colorectal cancer cells although biological activity was not evident.

14.
Pharmaceuticals (Basel) ; 14(11)2021 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-34832939

RESUMEN

Many bacteriophages are obligate killers of bacteria. That this property could be medically useful was first recognized over one hundred years ago, with 2021 being the 100-year anniversary of the first clinical phage therapy publication. Here we consider modern use of phages in clinical settings. Our aim is to answer one question: do phages serve as effective anti-bacterial infection agents when used clinically? An important emphasis of our analyses is on whether phage therapy-associated anti-bacterial infection efficacy can be reasonably distinguished from that associated with often coadministered antibiotics. We find that about half of 70 human phage treatment reports-published in English thus far in the 2000s-are suggestive of phage-mediated anti-bacterial infection efficacy. Two of these are randomized, double-blinded, infection-treatment studies while 14 of those studies, in our opinion, provide superior evidence of a phage role in observed treatment successes. Roughly three-quarters of these potentially phage-mediated outcomes are based on microbiological as well as clinical results, with the rest based on clinical success. Since many of these phage treatments are of infections for which antibiotic therapy had not been successful, their collective effectiveness is suggestive of a valid utility in employing phages to treat otherwise difficult-to-cure bacterial infections.

15.
Mater Sci Eng C Mater Biol Appl ; 124: 112051, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33947545

RESUMEN

Three-dimensional (3D) cell culture systems include bioengineered microenvironments that mimic the complexity of human tissues and organs in vitro. Robust biological models, like organoids and spheroids, rely on biomaterials to emulate the biochemical and biomechanical properties found in the extracellular matrix (ECM). Collagen (COL) is the main protein component of the ECM and has been used to generate fibrous matrices for 3D cell culture. Whilst neat COL gels are commonly blended with inert polymers to improve their poor mechanical properties, whether nanocellulose (NC) fibers interact or can develop some synergic bioactive effect to support organoid systems has never been demonstrated. Here, we investigate collagen-nanocellulose (COL-NC) hydrogels as a thermo-responsive matrix for the formation and growth of intestinal organoids. Cellulose nanofibres grafted with fibronectin-like adhesive sites form a porous network with type I collagen, presenting a sol-gel transition and viscoelastic profile similar to those of standard animal-based matrices. Crypts embedded in COL-NC form organoids with evidence of epithelial budding. Cell viability and metabolic activity are preserved as well as the expression of key cell markers. The stiffness of COL-NC hydrogels is shown to be a determinant element for the formation and development organoids. COL-NC hydrogels provide an affordable, performant thermo-responsive and sustainable matrix for organoid growth.


Asunto(s)
Hidrogeles , Organoides , Animales , Técnicas de Cultivo de Célula , Colágeno , Matriz Extracelular , Humanos
16.
J Biomed Mater Res B Appl Biomater ; 109(11): 1689-1697, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33694280

RESUMEN

Prior to transfusion of red blood cells (RBCs), recipients must be tested for the presence of alloantibodies to avoid immune complications. Liquid-preserved reagent RBCs with known blood group antigen phenotypes are used for testing. However, these reagents have practical constraints, including limited shelf-life and require constant refrigeration. To address these issues, we explore the effects of rapid freeze-drying conditions with trehalose cryoprotectant (0.1-1 M concentrations) on human RBCs and storage of freeze-dried RBCs (FDRBCs) at room temperature (RT) for up to 12 months. We report that rapid freeze-drying of RBCs for 2.5 hr with 0.5 M trehalose achieves recoverable cells with near-normal morphological shape, although size-reduced. The FDRBCs are metabolically active and functional in antibody-agglutination tests by the column agglutination test (CAT) for ABO and Rhesus-D blood group antigens. Expression of the Duffy blood group protein (CD234) decreases by 50% after freeze-drying RBCs. The initial recovery rate is ≤25%; however, 43% of these FDRBCs are still recoverable after RT storage for 12 months. In this proof-of-principle study, we show that rapid freeze-drying can stabilize RBCs. Further refinements to improve the recovery rate and preservation of antigenic epitopes will make FDRBCs a practical alternative source of reagent RBCs for pre-transfusion alloantibody identification.


Asunto(s)
Conservación de la Sangre , Crioprotectores/química , Eritrocitos/química , Isoanticuerpos/química , Trehalosa/química , Liofilización , Humanos
17.
Mater Sci Eng C Mater Biol Appl ; 120: 111742, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-33545884

RESUMEN

A crucial factor in the pathogenesis of orthopedics associated infections is that bacteria do not only colonize the implant surface but also the surrounding tissues. This study aimed to engineer an antimicrobial release coating for stainless steel (SS) surfaces, to impart them with the ability to prevent Staphylococci colonization. Chlorhexidine (CHX) was immobilized using two polydopamine (pDA)-based approaches: a one-pot synthesis, where CHX is dissolved together with dopamine before its polymerization; and a two-step methodology, comprising the deposition of a pDA layer to which CHX is immobilized. To modulate CHX release, an additional layer of pDA was also added for both strategies. Immobilization of CHX using a one-step approach yielded surfaces with a more homogenous coating and less roughness than the other strategies. The amount of released CHX was lower for the one-step approach, as opposed to the two-step approach yielding the higher release, which could be decreased by applying an outward layer of pDA. Both one and two-step approaches provided the surfaces with the ability to prevent bacterial colonization of the surface itself and kill most of bacteria in the bulk phase up to 10 days. This long-term antimicrobial performance alluded a stable and enduring immobilization of CHX. In terms of biocompatibility, the amount of CHX released from the one-step approach did not compromise the growth of mammalian cells, contrary to the two-step strategy. Additionally, the few bacteria that managed to adhere to surfaces modified with one-step approach did not show evidence of resistance towards CHX. Overall data underline that one-step immobilization of CHX holds great potential to be further applied in the fight against orthopedic devices associated infections.


Asunto(s)
Antiinfecciosos , Clorhexidina , Animales , Antibacterianos , Clorhexidina/farmacología , Dopamina , Acero Inoxidable
18.
Front Cell Infect Microbiol ; 10: 550505, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33262953

RESUMEN

Modern medicine is currently facing huge setbacks concerning infection therapeutics as microorganisms are consistently knocking down every antimicrobial wall set before them. The situation becomes more worrying when taking into account that, in both environmental and disease scenarios, microorganisms present themselves as biofilm communities that are often polymicrobial. This comprises a competitive advantage, with interactions between different species altering host responses, antimicrobial effectiveness, microbial pathogenesis and virulence, usually augmenting the severity of the infection and contributing for the recalcitrance towards conventional therapy. Pseudomonas aeruginosa and Candida albicans are two opportunistic pathogens often co-isolated from infections, mainly from mucosal tissues like the lung. Despite the billions of years of co-existence, this pair of microorganisms is a great example on how little is known about cross-kingdom interactions, particularly within the context of coinfections. Given the described scenario, this study aimed to collect, curate, and analyze all published experimental information on the molecular basis of P. aeruginosa and C. albicans interactions in biofilms, in order to shed light into key mechanisms that may affect infection prognosis, increasing this area of knowledge. Publications were optimally retrieved from PubMed and Web of Science and classified as to their relevance. Data was then systematically and manually curated, analyzed, and further reconstructed as networks. A total of 641 interactions between the two pathogens were annotated, outputting knowledge on important molecular players affecting key virulence mechanisms, such as hyphal growth, and related genes and proteins, constituting potential therapeutic targets for infections related to these bacterial-fungal consortia. Contrasting interactions were also analyzed, and quorum-sensing inhibition approaches were highlighted. All annotated data was made publicly available at www.ceb.uminho.pt/ISCTD, a database already containing similar data for P. aeruginosa and Staphylococcus aureus communication. This will allow researchers to cut on time and effort when studying this particular subject, facilitating the understanding of the basis of the inter-species and inter-kingdom interactions and how it can be modulated to help design alternative and more effective tailored therapies. Finally, data deposition will serve as base for future dataset integration, whose analysis will hopefully give insights into communications in more complex and varied biofilm communities.


Asunto(s)
Coinfección , Pseudomonas aeruginosa , Biopelículas , Candida albicans , Comunicación , Humanos , Percepción de Quorum
19.
Rev. Bras. Psicoter. (Online) ; 22(3): 81-93, 20200000.
Artículo en Portugués | INDEXPSI, LILACS | ID: biblio-1349384

RESUMEN

O presente artigo tem como objetivo analisar as dimensões do self na perspectiva da terapia cognitiva pós-Racionalista de Vittorio Guidano. Trata-se de um estudo qualitativo, exploratório e teórico, que teve como fonte a literatura especializada na área. Apresenta os principais conceitos e formulações da terapia cognitivo pós-racionalista, descrevendo o self como um processo emocional, afetivo e cognitivo, que se estabelece nos níveis tácito e explícito. Analisa também a dimensão autopoética e ortogenética, situando o self como um sistema complexo, que se autoproduz e se complexifica a partir de transformações internas. Conclui que os vínculos afetivos possuem um papel fundamental para a estruturação de tonalidades emotivas, que atuam como unidades organizadoras do autoconhecimento. Essas unidades possibilitam conhecer a forma específica que assume a auto-organização no desenvolvimento da identidade.(AU)


This article aims to analyze the dimensions of the Self in the perspective of Vittorio Guidanos Post-Rationalist Cognitive Therapy. This is a qualitative, exploratory and theoretical study, based on specialized literature in the area. It presents the main concepts and formulations of Post-Rationalist Cognitive Therapy, describing the Self as an emotional, affective and cognitive process, which is established on the tacit and explicit levels. It also analyzes the auto-poetic and orthogenetic dimension, placing the Self as a complex system, which self-produces and becomes more complex based on internal transformations. It concludes that affective bonds play a fundamental role in structuring emotional tones, which act as organizing units for the sense of itself. These units make it possible to know the specific form that self-organization takes in the development of the identity.(AU)


Este artículo tiene como objetivo analizar las dimensiones del "sí mismo" en la perspectiva de la Terapia Cognitiva Posracionalista de Vittorio Guidano. Este es un estudio cualitativo, exploratorio y teórico, basado en literatura especializada en el área. Presenta los principales conceptos y formulaciones de la Terapia Cognitiva PostRacionalista, describiendo el "sí mismo" como un proceso emocional, afectivo y cognitivo, que se establece en los niveles tácito y explícito. También analiza la dimensión autopoética y ortogenética, colocando el "sí mismo" como un sistema complejo, que se auto-produce y se vuelve más complejo en función de las transformaciones internas. Concluye que los vínculos afectivos tienen un papel fundamental en la estructuración de los matices emocionales, que actúan como unidades organizadoras para el sentido de uno mismo. Estas unidades permiten conocer la forma específica que toma la autoorganización en el desarrollo del "sí mismo".(AU)


Asunto(s)
Cognición , Emociones , Apego a Objetos
20.
Artículo en Inglés | MEDLINE | ID: mdl-32974221

RESUMEN

Cystic fibrosis (CF) disease provokes the accumulation of thick and viscous sputum in the lungs, favoring the development of chronic and polymicrobial infections. Pseudomonas aeruginosa is the main bacterium responsible for these chronic infections, and much of the difficulty involved in eradicating it is due to biofilm formation. However, this could be mitigated using adjuvant compounds that help or potentiate the antibiotic action. Therefore, the main goal of this study was to search for substances that function as adjuvants and also as biofilm-controlling compounds, preventing or dismantling P. aeruginosa biofilms formed in an in vitro CF airway environment. Dual combinations of compounds with subinhibitory (1 and 2 mg/L) and inhibitory concentrations (4 mg/L) of ciprofloxacin were tested to inhibit the bacterial growth and biofilm formation (prophylactic approach) and to eradicate 24-h-old P. aeruginosa populations, including planktonic cells and biofilms (treatment approach). Our results revealed that aspartic acid (Asp) and succinic acid (Suc) restored ciprofloxacin action against P. aeruginosa. Suc combined with 2 mg/L of ciprofloxacin (Suc-Cip) was able to eradicate bacteria, and Asp combined with 4 mg/L of ciprofloxacin (Asp-Cip) seemed to eradicate the whole 24-h-old populations, including planktonic cells and biofilms. Based on biomass depletion data, we noted that Asp induced cell death and Suc seemed somehow to block or reduce the expression of ciprofloxacin resistance. As far as we know, this kind of action had not been reported up till now. The presence of Staphylococcus aureus and Burkholderia cenocepacia did not affect the efficacy of the Asp-Cip and Suc-Cip therapies against P. aeruginosa and, also important, P. aeruginosa depletion from polymicrobial communities did not create a window of opportunity for these species to thrive. Rather the contrary, Asp and Suc also improved ciprofloxacin action against B. cenocepacia. Further studies on the cytotoxicity using lung epithelial cells indicated toxicity of Suc-Cip caused by the Suc. In conclusion, we provided evidences that Asp and Suc could be potential ciprofloxacin adjuvants to eradicate P. aeruginosa living within polymicrobial communities. Asp-Cip and Suc-Cip could be promising therapeutic options to cope with CF treatment failures.


Asunto(s)
Coinfección , Fibrosis Quística , Infecciones por Pseudomonas , Antibacterianos/farmacología , Ácido Aspártico , Biopelículas , Ciprofloxacina/farmacología , Fibrosis Quística/complicaciones , Humanos , Pruebas de Sensibilidad Microbiana , Infecciones por Pseudomonas/tratamiento farmacológico , Pseudomonas aeruginosa , Ácido Succínico
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