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1.
Artigo em Inglês | MEDLINE | ID: mdl-32752246

RESUMO

Within a socio-situational and socio-behavioural context, the relationships between the Big Five personality traits and the academic confidence of university students and how they differed by sex of the student was explored. Previous research has identified both conscientiousness and academic confidence as being linked to university performance. In respect of sex, female students have been found to score higher on all of the Big Five measures, whereas the relationship between sex and academic confidence has been mixed. Using self-report measures of personality and academic confidence from 1523 Spanish students, it was found that the female students were more confident in their grades, studying and attendance components of academic confidence and had higher scores for conscientiousness, agreeableness and neuroticism personality measures. A multiple regression analysis found that personality predicts academic confidence, with conscientiousness being the trait that statistically loaded the most strongly. This research further confirms the validity of the Academic Behavioural Confidence scale and suggests that measures of personality and, especially, academic confidence could be usefully used in student support situations to help students acquire the strategies and skills that lead to successful university study. It is suggested that further research in the area needs to include outcome or achievement measures and measures of hypothetical constructs, such as personality and academic confidence, that go beyond self-report measures.

2.
J Mater Chem B ; 2020 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-32627783

RESUMO

Tumor-derived extracellular vesicles have emerged as an alternative source of cancer biomarkers in liquid biopsies. Despite their clinical potential, traditional methods for isolation and analysis have hampered their translation into the clinic. The use of nanomaterial-based biosensors can speed up the development of analytical methods for quantifying extracellular vesicles in a specific, highly reproducible, robust, fast and inexpensive way. Here we review the utility of extracellular vesicles as a novel type of liquid biopsies and the recent advances in nanoparticle-based biosensors for their analysis. We aim to emphasise the limitations and challenges that hinder extracellular vesicle analysis using these biosensors and point out potential solutions.

3.
Small ; : e2003303, 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32700469

RESUMO

Nanotechnologies have reached maturity and market penetration that require nano-specific changes in legislation and harmonization among legislation domains, such as the amendments to REACH for nanomaterials (NMs) which came into force in 2020. Thus, an assessment of the components and regulatory boundaries of NMs risk governance is timely, alongside related methods and tools, as part of the global efforts to optimise nanosafety and integrate it into product design processes, via Safe(r)-by-Design (SbD) concepts. This paper provides an overview of the state-of-the-art regarding risk governance of NMs and lays out the theoretical basis for the development and implementation of an effective, trustworthy and transparent risk governance framework for NMs. The proposed framework enables continuous integration of the evolving state of the science, leverages best practice from contiguous disciplines and facilitates responsive re-thinking of nanosafety governance to meet future needs. To achieve and operationalise such framework, a science-based Risk Governance Council (RGC) for NMs is being developed. The framework will provide a toolkit for independent NMs' risk governance and integrates needs and views of stakeholders. An extension of this framework to relevant advanced materials and emerging technologies is also envisaged, in view of future foundations of risk research in Europe and globally.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32560173

RESUMO

Achievement emotions constitute one important variable among the many variables of students' learning. The aim of this research was to analyze the differential effect of university students' levels of self-regulation (1 = low, 2 = medium and 3 = high), and of their level of perceived stress in three academic situations (1 = class, 2 = study time and 3 = testing), on the type of achievement emotionality they experience (positive and negative emotions). The following hypotheses were established: (1) a higher level of student self-regulation would be accompanied by higher levels of positive emotionality and lower levels of negative emotionality and (2) a higher level of situational stress would predispose higher levels of negative emotionality and lower levels of positive emotionality. A total of 520 university students completed three self-reports with validated inventories. Descriptive, correlational, and structural prediction analyses (SEM) were performed, as well as 3 × 3 ANOVAs, under an ex post facto design by selection. The results showed overall fulfillment of the hypotheses, except for a few specific emotions. Implications for prevention and psychoeducational guidance in the sphere of university education are discussed.

5.
Artigo em Inglês | MEDLINE | ID: mdl-32443929

RESUMO

The study focused on the analysis of linear relations between personality, self-regulation, coping strategies and achievement emotions. The main objective was to establish a model of linear, empirical, associative to infer needs and proposals for intervening in emotional health in the different profiles of university students. A total of 642 undergraduate students participated in this research. Evidence of associative relations between personality factors, self-regulation and coping strategies was found. The neuroticism factor had a significant negative associative relationship with Self-Regulation both globally and in its factors; especially important was its negative relation to decision making, and coping strategies focused in emotion. The results of Structural Equation Model showed an acceptable model of relationships, in each emotional context. Results and practical implications are discussed.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32235741

RESUMO

Achievement emotions that the university student experiences in the learning process can be significant in facilitating or interfering with learning. The present research looked for linear and predictive relations between university students' achievement emotions, coping strategies, and engagement-burnout, in three different learning situations (classroom, study time, and testing). Hypotheses were identified for a possible model that would analyze the two facets of perfectionism based on these relations. In the case of perfectionistic strivings, the test hypothesis was that positive emotions would predispose the use of problem-focused coping strategies and an emotional state of engagement; in the case of perfectionistic concerns, however, negative emotions would predispose the use of emotion-focused strategies and a state of burnout. A total of 654 university students participated in the study, using an online tool to complete validated questionnaires on the three study variables. All students provided informed consent and corresponding permissions. Given the ex-post facto linear design, the predictions could be verified for each situation by means of logistic regression analyses and Structural Equations Models (SEM). Empirical results lent support, in varying degree, to the proposed theoretical relations. The testing situation was of particular interest. We discuss implications for perfectionism research and for the practice of prevention, education and health care in the university setting.

7.
Animals (Basel) ; 10(4)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244765

RESUMO

The objective of this study was to evaluate the effect of replacing cereals and protein concentrates in a high-cereal concentrate (control) for light lambs with corn distiller's dried grains with solubles (DDGS; 18%), dried citrus pulp (DCP; 18%), and exhausted olive cake (EOC; 8%) in a byproduct (BYP) concentrate on growth performance, digestibility, ruminal fermentation, and plasma metabolites. Two homogeneous groups of Lacaune lambs (13.8 kg ± 0.25 kg) were fed one of each concentrates and barley straw ad libitum until reaching about 26 kg body weight. There were no differences between groups on feed intake, average daily gain, or feed conversion ratio, but the control diet had greater (p < 0.001) dry matter digestibility. Diet had no effect on post-mortem ruminal pH and total volatile fatty acid concentrations and profile, but NH3-N concentrations were lower (p = 0.003) for the BYP-fed group compared with the control one. However, plasma concentrations of amino acids, total proteins, urea, and hepatic enzymes were not affected by the diet. In conclusion, 44% of feed ingredients in the concentrate for light lambs can be replaced with a mixture of corn DDGS, DCP, and EOC without negatively affecting growing performance and animal health.

8.
J Colloid Interface Sci ; 573: 278-286, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32283416

RESUMO

The combination of different bioimaging techniques, mainly in the field of oncology, allows circumventing the defects associated with the individual imaging modalities, thus providing a more reliable diagnosis. The development of multimodal endogenous probes that are simultaneously suitable for various imaging modalities, such as magnetic resonance imaging (MRI), X-ray computed tomography (CT) and luminescent imaging (LI) is, therefore, highly recommended. Such probes should operate in the conditions imposed by the newest imaging equipment, such as MRI operating at high magnetic fields and dual-energy CT. They should show, as well, high photoluminescence emission intensity for their use in optical imaging and present good biocompatibility. In this context, we have designed a single nanoprobe, based on a core-shell architecture, composed of a luminescent Eu3+:Ba0.3Lu0.7F2.7 core surrounded by an external HoF3 shell that confers the probe with very high magnetic transverse relaxivity at high field. An intermediate, optically inert Ba0.3Lu0.7F2.7 layer was interposed between the core and the shell to hinder Eu3+-Ho3+ cross-relaxation and avoid luminescence quenching. The presence of Ba and Lu, with different K-edges, allows for good X-ray attenuation at high and low voltages. The core-shell nanoparticles synthesized are good potential candidates as trimodal bioprobes for MRI at high field, dual-energy CT and luminescent imaging.

9.
Viruses ; 12(1)2020 01 07.
Artigo em Inglês | MEDLINE | ID: mdl-31936013

RESUMO

The aim of this study is to evaluate the performance characteristics of the LIAISON XL Zika Capture IgM II. For this purpose we tested 128 samples obtained from recent infections caused by the Zika (ZIKV; 74 samples), dengue (DENV; 10 samples), chikungunya (CHIK V; 11 samples), rubella (RUBV; 10 samples) and measles (MeV; 10 samples) viruses, as well as human parvovirus B19 (HPVB19; 13 samples). The results of the assay under evaluation are compared with those obtained from an indirect immunofluorescence (IIF) assay, and the discrepancies are resolved by considering other laboratory results (PCR and a plaque-reduction neutralization test). The LIAISON showed excellent sensitivity (100%). The specificity (91.25%) was hampered by some false-positive results in recent dengue virus, chikungunya virus, measles virus and human parvovirus B19 infections. The method evaluated is adequate, but the low specificity makes it necessary to consider the clinical and epidemiological contexts of patients, as well as other laboratory results.

10.
Nanomedicine (Lond) ; 14(23): 3035-3055, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31686580

RESUMO

Aim: To study the difference in biodistribution of gold nanoprisms (NPr) and nanorods (NR), PEGylated to ensure colloidal stability. Materials & methods: Surface changes were studied for nanoparticles in different media, while the biodistribution was quantified and imaged in vivo. Results: Upon interaction with the mouse serum, NR showed more abrupt changes in surface properties than NPr. In the in vivo tests, while NPr accumulated similarly in the spleen and liver, NR showed much higher gold presence in the spleen than in liver; together with some accumulation in kidneys, which was nonexistent in NPr. NPr were cleared from the tissues 2 months after administration, while NR were more persistent. Conclusion: The results suggest that the differential biodistribution is caused by size-/shape-dependent interactions with the serum.

11.
Front Psychol ; 10: 2070, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31620044

RESUMO

The SRL vs.ERL Theory predicts that a student's own self-regulation and the regulatory nature of the context are factors that jointly determine the student's level of motivational-affective variables. However, this principle has not yet been verified in the case of achievement emotions. The aim of this research was to test this prediction, with the hypothesis that students' level of self-regulation (low-medium-high), in interaction with the regulatory nature of the teaching (low-medium-high), would determine positive or negative emotions as well as the degree of burnout/engagement. A total of 440 university students completed validated questionnaires on self-regulation; regulatory teaching; achievement emotions in class, in study and in testing situations; and on burnout/engagement. Using a quasi-experimental design by selection, ANOVAs and MANOVAs (3 × 3; 5 × 1) were carried out. The results confirmed that the level of self-regulation and the level of external regulation jointly determined university students' level of achievement emotions, as well as their level of burnout/engagement. Based on these results, a five-level progressive scale was configured. We conclude that this scale may be useful and adequate as a heuristic technique or model for understanding and analyzing the type of student-teacher interaction that is taking place in the university classroom, and thereby learn the probability of stressful effects and the students' level of emotional health.

12.
Theranostics ; 9(23): 6867-6884, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31660074

RESUMO

The low efficiency of photodynamic therapy (PDT) is caused by tumor hypoxia and the adaptive immune resistance/evasion of tumor cells, while the currently emerging immune checkpoint therapy restores the intrinsic immune capacities but can't directly attack the tumor cells. Methods: Herein we report an integrated nanoplatform that combines PDT with immunotherapy to enhance photodynamic therapeutic effects and simultaneously inhibit tumor cells resistance/evasion. To achieve this, we fabricated Mn@CaCO3/ICG nanoparticles and loaded them with PD-L1-targeting siRNA. Results: Thanks to the protection of CaCO3 on the loaded ICG and the oxygen produced by MnO2, an enhanced photodynamic therapeutic effect in vitro was observed. In vivo experiments demonstrated that the nanoplatform could efficiently deliver the loaded drug to the tumor tissues and significantly improve tumor hypoxia, which further contributes to the therapeutic effect of PDT in vivo. Moreover, the synergistic benefits derived from the siRNA, which silenced the checkpoint gene PD-L1 that mediates the immune resistance/evasion, resulted in a surprising therapeutic effect to rouse the immune system. Conclusions: The combination treatment strategy has great potential to be developed as a new and robust method for enhanced PDT therapy with high efficiency and a powerful antitumor immune response based on PD-L1 blockade.

14.
J Mater Chem B ; 7(41): 6412-6419, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31642855

RESUMO

Microorganisms such as bacteria, fungi, algae and moulds are highly proficient at colonizing artistic and architectural heritage. The irreparable damage they cause to unique artefacts results in immeasurable cultural and societal losses to our shared cultural heritage, which represent an important social and economic resource for Europe. With the overall aim of preventing fungal deterioration of paper artefacts, we report the use of magnesium oxide nanoparticles (MgO NPs) of average diameter 12 nm as potent antifungal agents against fungi commonly found colonising paper heritage: A. niger, C. cladosporioides and T. reesei. Dispersions of MgO NPs on original 18th century paper samples from the Archives of the Spanish Royal Botanic Garden were effective at preventing fungal colonisation without altering the appearance of the paper artefacts. Importantly, MgO NPs also inhibit cellulase activity in the filamentous fungi T. resei and A. niger, two of the principle biodeteriogens of cellulosic materials. In addition, our report provides three simple new procedures for studying the fungal colonisation prevention properties of nanomaterials on paper samples. Overall this opens the door to the use of colourless, low-cost, and scalable nanomaterials for preventing biodeterioration in cellulose-based artefacts.

15.
Front Psychol ; 10: 1919, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31507487

RESUMO

The proliferation of research production in Psychology as a science has been increasing exponentially. This situation leads to the necessity of organizing the research production into different levels of analysis that make it possible to delimit each research domain. The objective of this analysis is to clearly distinguish the different levels of research: micro-analysis, molecular, and molar. Each level is presented, along with an analysis of its benefits and limitations. Next, this analysis is applied to the topics of Executive Functions, Self-Regulation, and External Regulation. Conclusions, limitations, and implications for future research are offered, with a view toward a better connection of research production across the different levels, and an allusion to ethical considerations.

16.
PLoS One ; 14(9): e0220684, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31479462

RESUMO

Bacterial resistance to antibiotics is widely regarded as a major public health concern with last resort MRSA treatments like vancomycin now encountering resistant strains. TFDs (Transcription Factor Decoys) are oligonucleotide copies of the DNA-binding sites for transcription factors. They bind to and sequester the targeted transcription factor, thus inhibiting transcription of many genes. By developing TFDs with sequences aimed at inhibiting transcription factors controlling the expression of highly conserved bacterial cell wall proteins, TFDs present as a potential method for inhibiting microbial growth without encountering typical resistance mechanisms. However, the efficient protection and delivery of the TFDs inside the bacterial cells is a critical step for the success of this technology. Therefore, in our study, specific TFDs against S. aureus were complexed with two different types of nanocarriers: cationic nanostructured lipid carriers (cNLCs) and chitosan-based nanoparticles (CS-NCs). These TFD-carrier nanocomplexes were characterized for size, zeta potential and TFD complexation or loading efficiency in a variety of buffers. In vitro activity of the nanocomplexes was examined alone and in combination with vancomycin, first in methicillin susceptible strains of S. aureus with the lead candidate advancing to tests against MRSA cultures. Results found that both cNLCs and chitosan-based carriers were adept at complexing and protecting TFDs in a range of physiological and microbiological buffers up to 72 hours. From initial testing, chitosan-TFD particles demonstrated no visible improvements in effect when co-administered with vancomycin. However, co-delivery of cNLC-TFD with vancomycin reduced the MIC of vancomycin by over 50% in MSSA and resulted in significant decreases in viability compared with vancomycin alone in MRSA cultures. Furthermore, these TFD-loaded particles demonstrated very low levels of cytotoxicity and haemolysis in vitro. To our knowledge, this is the first attempt at a combined antibiotic/oligonucleotide-TFD approach to combatting MRSA and, as such, highlights a new avenue of MRSA treatment combining traditional small molecules drugs and bacterial gene inhibition.


Assuntos
Antibacterianos/administração & dosagem , Lipídeos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Nanoestruturas , Fatores de Transcrição/administração & dosagem , Vancomicina/administração & dosagem , Antibacterianos/química , Quitosana/química , Portadores de Fármacos , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Estabilidade de Medicamentos , Sinergismo Farmacológico , Hemólise/efeitos dos fármacos , Humanos , Lipídeos/química , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Modelos Biológicos , Nanoestruturas/química , Infecções Estafilocócicas/microbiologia , Fatores de Transcrição/química
17.
Nanomedicine (Lond) ; 14(18): 2409-2422, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31456488

RESUMO

Aim: To determine whether a p38 MAPK inhibitor incorporated into nanoemulsion-based chitosan nanocapsules can reduce the activity of this kinase in the brain through their nasal administration in mice. Materials & methods: We selected the p38 MAPK inhibitor PH797804, an ATP-competitive inhibitor of p38α encapsulated in nanoemulsion-based chitosan nanocapsules. Biological effect was evaluated in microglial and neuronal cells in vitro and in ex vivo and in vivo systems, in a mouse model of Alzheimer's disease. Results: Encapsulated inhibitor retains enzymatic inhibitory activity and tissue penetration capacity in vitro, ex vivo and in vivo. Conclusion: Nasal administration of chitosan nanocapsules can be an effective approach for brain-restricted reduction of p38 MAPK activity, thus reducing the side effects of systemic administration.

18.
J Colloid Interface Sci ; 554: 520-530, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31330425

RESUMO

A one-pot simple procedure for the synthesis of uniform, ellipsoidal Eu3+-doped sodium lanthanum tungstate and molybdate (NaLa(XO4)2, X  = W, Mo) nanophosphors, functionalized with carboxylate groups, is described. The method is based on a homogeneous precipitation process at 120 °C from appropriate Na+, Ln3+ and tungstate or molybdate precursors dissolved in ethylene glycol/water mixtures containing polyacrylic acid. A comparative study of the luminescent properties of both luminescent materials as a function of the Eu3+ doping level has been performed to find the optimum nanophosphor, whose efficiency as X-ray computed tomography contrast agent is also evaluated and compared with that of a commercial probe. Finally, the cell viability and colloidal stability in physiological pH medium of the optimum samples have also been studied to assess their suitability for biomedical applications.


Assuntos
Meios de Contraste/química , Európio/química , Lantânio/química , Substâncias Luminescentes/química , Molibdênio/química , Compostos de Tungstênio/química , Animais , Chlorocebus aethiops , Meios de Contraste/síntese química , Substâncias Luminescentes/síntese química , Tomografia Computadorizada por Raios X , Compostos de Tungstênio/síntese química , Células Vero
19.
Animals (Basel) ; 9(7)2019 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-31277374

RESUMO

The objective of this study was to analyze the efficacy of a treatment (MAH) of sunflower seed (SS) and meal (SM) with a malic acid solution (1 M; 400 mL/kg) and heating (150 °C, 2 h) to protect protein against rumen degradation and to improve the growth of lambs. Two homogeneous groups of 12 Lacaune lambs each (14.2 ± 0.35 kg body weight) were fed either a concentrate including untreated SS and SM or a concentrate with MAH-treated SS and SM. Lambs were fed concentrate and barley straw ad libitum for 40 days (about 26 kg body weight); feed intake and growth of lambs were recorded; blood samples were taken on days 0, 20, and the slaughter day for analysis of urea-N and amino acid-N; diet digestibility was determined; and ruminal and cecal samples were collected after slaughter. The in vitro incubation of both concentrates with sheep ruminal fluid for 12 h showed that the MAH-treatment tended to reduce NH3-N concentrations and increased propionate production. However, there were no differences (p > 0.05) between groups in any of the tested variables in the in vivo trial.

20.
Dalton Trans ; 48(30): 11480-11491, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31290885

RESUMO

Manganese/iron ferrite nanoparticles with different Mn2+/3+ doping grades have been prepared by a thermal decomposition optimized approach so as to ascertain the doping effect on magnetic properties and, especially, on the magnetic hyperthermia response. The oxidation state and interstitial position of Mn in the spinel structure is found to be critical. The particle size effect has also been studied by growing one of the prepared samples (from 10 to 15 nm in diameter) by a seed mediated growth mechanism. After analyzing the main structural and chemical parameters such as the Mn/Fe rate, crystalline structure, particle diameter, shape and organic coating, some Mn doping induced changes have been observed, such as the insertion of Mn2+ cations yielded more anisotropic shapes. Magnetic characterization, carried out by DC magnetometry (M(H), M(T)) and electron magnetic resonance (EMR) techniques, has shown interesting differences between samples with varying compositions. Lower Mn doping levels lead to larger saturation magnetization values, while an increase of the Mn content causes the decrease of the effective magnetic anisotropy constant at low T. The homogeneous magnetic response under applied magnetic fields, together with the great effect of nanoparticle size and shape in such a response, has been confirmed by the EMR analysis. Finally, a detailed magnetic hyperthermia analysis has demonstrated the large influence of NP size and shape on the magnetic hyperthermia response. The optimized Mn0.13Fe2.87O4_G sample with a diameter of 15 nm and slightly truncated octahedral shape is presented as an interesting candidate for future magnetic hyperthermia mediated biomedical treatments.

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