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1.
Polymers (Basel) ; 14(12)2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35745916

RESUMO

The production of green plastic materials from defatted silkworm meal (SW) through a scalable technique (e.g., injection moulding) would permit the revalorization of a by-product of the textile industry. The textile by-product contains an estimable protein content (~50%) which can justify its applicability in the field of eco-materials. Thus, SW-based materials have been processed and characterized, sometimes requiring the addition of another biodegradable polymer, such as polycaprolactone (PCL), in the formulation. Thermomechanical, tensile and water uptake properties have been assessed at different PCL contents (from 0 to 20%). The viscoelasticity of the plastic composites when heated was greatly affected by the melting point of PCL, which also led generally to an increase in their extensibility and resistance. However, this effect of PCL was diminished when composites were processed at higher moulding temperatures. As PCL possesses a hydrophobic character, a decrease in the water uptake was generally detected as PCL content increased, which could also be related to the lower plasticizer content in the formulation. Silkworm meal is an adequate ingredient to consider in the production of green plastic materials that would eventually add value to a main by-product of the sericulture industry.

2.
Pediatr Pulmonol ; 57(5): 1339-1347, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35224889

RESUMO

BACKGROUND AND OBJECTIVES: Accurate and readily available biomarkers to predict the clinical course of bronchiolitis would enable enhanced decision-making in this setting. We explored the relationship of several biochemical parameters available at the pediatric emergency care setting with the need of advanced respiratory support (ARS): continuous positive airway pressure (CPAP), biphasic positive airway pressure (BiPAP), or invasive mechanical ventilation (MV) in bronchiolitis. METHODS: Single-center, prospective, observational, including infants aged less than 12 months diagnosed with acute bronchiolitis at the Pediatric Emergency Department. Determination of plasmatic values of several laboratory tests was performed at the time of hospital admission. Multivariate logistic analysis identified independent predictors for need of ARS. RESULTS: From October 1, 2018 to May 1, 2020, we recruited 149 infants (58% males; median age of 1 [0.5-2.5] month). Thirty-seven (25%) cases required ARS. After adjusting by age, bacterial superinfection, and comorbidities in the multivariate analysis, only higher levels of glycemia (p = 0.001), C-reactive protein (CRP) (p = 0.028), CRP/albumin ratio (p = 0.032), and NT-proBNP (p = 0.001) remained independently associated with ARS. These biomarkers reached moderate prediction accuracy with area under the curve of receiver operator curve curves ranging from 0.701 to 0.830 (p = 0.001). All they presented relatively high specificity (0.75-0.84) and negative predictive values (0.77-0.89) with low sensitivity and positive predictive values. They also correlated significantly with length of stay hospitalization (p = 0.001). CONCLUSION: Increased plasmatic levels of CRP, CRP/albumin ratio, glycemia, and NT-proBNP at hospital admission are associated with the need for ARS in infants with acute bronchiolitis.


Assuntos
Bronquiolite , Albuminas , Biomarcadores , Bronquiolite/diagnóstico , Bronquiolite/terapia , Criança , Pressão Positiva Contínua nas Vias Aéreas , Feminino , Humanos , Lactente , Masculino , Estudos Prospectivos
3.
Gels ; 7(4)2021 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-34698192

RESUMO

Chitosan-pectin hydrogels were prepared, and their rheological properties were assessed in order to select the best system to develop scaffolds by 3D printing. Hydrogels showed a weak gel behavior with shear thinning flow properties, caused by the physical interactions formed between both polysaccharides, as observed by FTIR analysis. Since systems with high concentration of pectin showed aggregations, the system composed of 2 wt% chitosan and 2 wt% pectin (CHI2PEC2) was selected for 3D printing. 3D printed scaffolds showed good shape accuracy, and SEM and XRD analyses revealed a homogeneous and amorphous structure. Moreover, scaffolds were stable and kept their shape and size after a cycle of compression sweeps. Their integrity was also maintained after immersion in PBS at 37 °C, showing a high swelling capacity, suitable for exudate absorption in wound healing applications.

4.
Polymers (Basel) ; 13(11)2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34072653

RESUMO

Composite materials based on proteins and carbohydrates normally offer improved water solubility, biodegradability, and biocompatibility, which make them attractive for a wide range of applications. Soy protein isolate (SPI) has shown superabsorbent properties that are useful in fields such as agriculture. Alginate salts (ALG) are linear anionic polysaccharides obtained at a low cost from brown algae, displaying a good enough biocompatibility to be considered for medical applications. As alginates are quite hydrophilic, the exchange of ions from guluronic acid present in its molecular structure with divalent cations, particularly Ca2+, may induce its gelation, which would inhibit its solubilization in water. Both biopolymers SPI and ALG were used to produce composites through injection moulding using glycerol (Gly) as a plasticizer. Different biopolymer/plasticizer ratios were employed, and the SPI/ALG ratio within the biopolymer fraction was also varied. Furthermore, composites were immersed in different CaCl2 solutions to inhibit the amount of soluble matter loss and to enhance the mechanical properties of the resulting porous matrices. The main goal of the present work was the development and characterization of green porous matrices with inhibited solubility thanks to the gelation of alginate.

5.
Foods ; 10(5)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33947093

RESUMO

A great amount of biowastes, comprising byproducts and biomass wastes, is originated yearly from the agri-food industry. These biowastes are commonly rich in proteins and polysaccharides and are mainly discarded or used for animal feeding. As regulations aim to shift from a fossil-based to a bio-based circular economy model, biowastes are also being employed for producing bio-based materials. This may involve their use in high-value applications and therefore a remarkable revalorization of those resources. The present review summarizes the main sources of protein from biowastes and co-products of the agri-food industry (i.e., wheat gluten, potato, zein, soy, rapeseed, sunflower, protein, casein, whey, blood, gelatin, collagen, keratin, and algae protein concentrates), assessing the bioplastic application (i.e., food packaging and coating, controlled release of active agents, absorbent and superabsorbent materials, agriculture, and scaffolds) for which they have been more extensively produced. The most common wet and dry processes to produce protein-based materials are also described (i.e., compression molding, injection molding, extrusion, 3D-printing, casting, and electrospinning), as well as the main characterization techniques (i.e., mechanical and rheological properties, tensile strength tests, rheological tests, thermal characterization, and optical properties). In this sense, the strategy of producing materials from biowastes to be used in agricultural applications, which converge with the zero-waste approach, seems to be remarkably attractive from a sustainability prospect (including environmental, economic, and social angles). This approach allows envisioning a reduction of some of the impacts along the product life cycle, contributing to tackling the transition toward a circular economy.

6.
Polymers (Basel) ; 13(5)2021 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-33802290

RESUMO

The replacement of common acrylic derivatives by biodegradable materials in the formulation of superabsorbent materials would lessen the associated environmental impact. Moreover, the use of by-products or biowastes from the food industry that are usually discarded would promote a desired circular economy. The present study deals with the development of superabsorbent materials based on a by-product from the meat industry, namely plasma protein, focusing on the effects of a freeze-drying stage before blending with glycerol and eventual injection molding. More specifically, this freeze-drying stage is carried out either directly on the protein flour or after its solubilization in deionized water (10% w/w). Superabsorbent materials obtained after this solubilization-freeze-drying process display higher Young's modulus and tensile strength values, without affecting their water uptake capacity. As greater water uptake is commonly related to poorer mechanical properties, the proposed solubilization-freeze-drying process is a useful strategy for producing strengthened hydrophilic materials.

7.
Artigo em Inglês | MEDLINE | ID: mdl-33546129

RESUMO

Inequalities between men and women in the workplace are reflected in professional sports, specifically football refereeing. This phenomenon sometimes becomes sexual harassment since it is a stereotypically considered male profession in which women are a minority. To measure that behavior, it is necessary to count on valid and reliable tools. Therefore, the goal of this study was to determine the factorial structure and the discriminant and convergent validity of the 'sexual experiences questionnaire', version of the Department of Defence (SEQ-DoD). Eighty-nine male football referees and ninety-four female football referees, with a mean age of 23.30 ± 4.85 years, participated in this studio conducted questionnaire in Andalusia, Spain. A confirmatory factor analysis was performed using the robust maximum-likelihood estimation method. The goodness of fit was assessed, and the factorial invariance was calculated to determine the stability of the model. Subsequently, the validity was confirmed. The results corroborated the validity and reliability of the questionnaire adapted to the population studied. Therefore, it can be used as a research instrument.


Assuntos
Futebol Americano , Assédio Sexual , Adolescente , Adulto , Análise Fatorial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , Espanha , Inquéritos e Questionários , Adulto Jovem
8.
Front Microbiol ; 11: 2006, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013743

RESUMO

Herpes simplex viruses (HSVs) type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent in the human population, and the infections they produce are lifelong with frequent reactivations throughout life. Both viruses produce uncomfortable and sometimes painful lesions in the orofacial and genital areas, as well as herpetic gingivostomatitis, among other clinical manifestations. At present, the most common treatments against HSVs consist of nucleoside analogs that target the viral polymerases. However, such drugs are poorly effective for treating skin lesions, as they only reduce in 1-2 days the duration of the herpetic lesions. Additionally, viral isolates resistant to these drugs can emerge in immunosuppressed individuals, and second-line drugs for such variants are frequently accompanied by adverse effects requiring medical supervision. Thus, novel or improved therapeutic drugs for treating HSV lesions are needed. Here, we assessed the potential antiviral activity of aqueous extracts obtained from two brown macroalgae, namely Macrocystis pyrifera and Durvillaea antarctica against HSVs. Both extracts showed antiviral activity against acyclovir-sensitive and acyclovir-resistant HSV-1 and HSV-2. Our analyses show that there is a significant antiviral activity associated with proteins in the extract, although other compounds also seem to contribute to inhibiting the replication cycle of these viruses. Evaluation of the algae extracts as topical formulations in an animal model of HSV-1 skin infection significantly reduced the severity of the disease more than acyclovir, as well as the duration of the herpetic lesions, when compared to mock-treated animals, with the D. antarctica extract performing best. Taken together, these findings suggest that these algae extracts may be potential phytotherapeutics against HSVs and may be useful for the treatment and reduction of common herpetic manifestations in humans.

9.
J Environ Manage ; 263: 110353, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32883472

RESUMO

Nowadays, as the world population is in need of creating alternative materials that can replace conventional plastics, microalgae biomass may be identified as a viable source for producing more environmentally friendly materials. Scenedesmus sp and Desmodesmus sp are the main components (~80%) of a microalgae consortium (MC) that first has been used to remove Nitrogen and Phosphorus from wastewater. The potential to develop bioplastic materials from MC considering its relatively high protein content (~48%) has been assessed in the present manuscript, using as a reference a commercial biomass rich an Arthrospira specie (AM) also present in the studied consortium. Bioplastics were obtained through injection moulding of blends obtained after mixing with different amounts of glycerol, and eventually characterized using Dynamic Mechanical Thermal Analysis (DMTA), water immersion and tensile tests. All bioplastics displayed a glass transition temperature around 60 °C, showing a thermoplastic behavior which is less pronounced in the CM based bioplastics. This would imply a greater thermal resistance of bioplastics produced from the biomass harvested in wastewater. Moreover, these bioplastics showed a lower ability to absorb water when immersed, due to the lower deformability displayed in the tensile tests. The mechanical properties of all samples, independently of the nature of the biomass, were improved when the presence of the biomass was higher. Therefore, results here presented prove the potential of valorisation of microalgae consortia used in the effective treatment of wastewater through the development of bioplastic materials.


Assuntos
Microalgas , Scenedesmus , Biomassa , Nitrogênio/análise , Fósforo , Águas Residuárias
10.
Front Microbiol ; 11: 139, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117158

RESUMO

Herpes simplex viruses type 1 (HSV-1) and type 2 (HSV-2) are highly prevalent within the human population and are characterized by lifelong infections and sporadic recurrences due to latent neuron infection. Upon reactivations, HSVs may manifest either, symptomatically or asymptomatically and be shed onto others through mucosae body fluids. Although, HSVs can produce severe disease in humans, such as life-threatening encephalitis and blindness, the most common symptoms are skin and mucosal lesions in the oro-facial and the genital areas. Nucleoside analogs with antiviral activity can prevent severe HSV infection, yet they are not very effective for treating skin manifestations produced by these viruses, as they only reduce in a few days at most the duration of lesions. Additionally, HSV variants that are resistant to these antivirals may arise, especially in immunosuppressed individuals. Thus, new antivirals that can reduce the severity and duration of these cutaneous manifestations would certainly be welcome. Here, we review currently available anti-herpetic therapies, novel molecules being assessed in clinical trials and new botanical compounds reported in the last 20 years with antiviral activities against HSVs that might represent future treatments against these viruses.

11.
Neural Regen Res ; 14(6): 1060-1068, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30762019

RESUMO

Spinal cord injury is a very common pathological event that has devastating functional consequences in patients. In recent years, several research groups are trying to find an effective therapy that could be applied in clinical practice. In this study, we analyzed the combination of different strategies as a potential therapy for spinal cord injury. Immunization with neural derived peptides (INDP), inhibition of glial scar formation (dipyridyl: DPY), as well as the use of biocompatible matrix (fibrin glue: FG) impregnated with bone marrow mesenchymal stem cells (MSCs) were combined and then its beneficial effects were evaluated in the induction of neuroprotection and neuroregeneration after acute SCI. Sprague-Dawley female rats were subjected to a moderate spinal cord injury and then randomly allocated into five groups: 1) phosphate buffered saline; 2) DPY; 3) INDP + DPY; 4) DPY+ FG; 5) INDP + DPY + FG + MSCs. In all rats, intervention was performed 72 hours after spinal cord injury. Locomotor and sensibility recovery was assessed in all rats. At 60 days after treatment, histological examinations of the spinal cord (hematoxylin-eosin and Bielschowsky staining) were performed. Our results showed that the combination therapy (DPY+ INDP + FG + MSCs) was the best strategy to promote motor and sensibility recovery. In addition, significant increases in tissue preservation and axonal density were observed in the combination therapy group. Findings from this study suggest that the combination theapy (DPY+ INDP + FG + MSCs) exhibits potential effects on the protection and regeneration of neural tissue after acute spinal cord injury. All procedures were approved by the Animal Bioethics and Welfare Committee (approval No. 178544; CSNBTBIBAJ 090812960) on August 15, 2016.

12.
Org Lett ; 21(3): 705-708, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30672295

RESUMO

An iodine-mediated Hofmann-Löffler reaction has been developed that enables the first enantioselective synthesis of nicotine based on this synthetic methodology. The effect of the free pyridine core on the involved electrophilic iodine reagents was explored in detail. The final synthesis proceeds under moderate reaction conditions that tolerate the free pyridine core. The same synthetic sequence is also applicable to a number of derivatives with higher substituted pyridine cores, including bipyridine derivatives.

13.
Chemistry ; 24(65): 17225-17229, 2018 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-30189118

RESUMO

An innovative approach to position-selective polyhalogenation of aliphatic hydrocarbon bonds is presented. The reaction proceeded within the Hofmann-Löffler manifold with amidyl radicals as the sole mediators to induce selective 1,5- and 1,6-hydrogen-atom transfer followed by halogenation. Multiple halogenation events of up to four innate C-H bond functionalizations were accomplished. The broad applicability of this new entry into polyhalogenation and the resulting synthetic possibilities were demonstrated for a total of 27 different examples including mixed halogenations.

14.
Org Lett ; 19(22): 6236-6239, 2017 11 17.
Artigo em Inglês | MEDLINE | ID: mdl-29112447

RESUMO

The transition-metal-free diastereoselective C(sp2)-C(sp3) cross-coupling between unprotected diols and boronic acids or potassium organotrifluoroborates is reported. Depending on the reaction conditions, the syn or the anti reaction products are obtained in a stereocomplementary fashion. This type of coupling is developed with alkenyl-, heteroaryl- and arylboron compounds as carbon nucleophiles.

15.
Rev. psicol. deport ; 18(3): 357-361, 2009. ilus
Artigo em Inglês | IBECS | ID: ibc-75452

RESUMO

Coaches are reference models for youth athletes and have a high degree of influence over them, and thus asuitable education is important. Therefore, the purpose of this study was to assess how a basketball coach progresses inthe transmission of a task climate during his basketball training sessions, after participating in a reflective educationalprogram focused on the coach's actions. In this study, a basketball coach and the two teams that he coached participated.All the players were between 14 and 15 years of age. The behavior of the coach was analyzed through an adaptation of theCoaching Behavior Assessment System (CBAS) (Smith, Smoll, & Hunt, 1977). The observational analysis was carried outby the research team, who was previously trained. Six sessions of observation were carried out, and inter- and intraobserverreliabilities of 97.6% were obtained. During three months, the coach participated in an educational programconsisting of six supervised cycles in which the premises established by Ames (1992) with the abbreviation TARGET werefollowed, in order to transmit a task climate during his coaching sessions.The results demonstrate a progression in the climate that was transmitted by the coach. In the first training session,the proportion of the climate that he transmitted as task was 65.67% and the ego climate was 34.43%, while in thepenultimate training session it was 85.11% for task versus 14.89% for ego, and this was the session with the greatestproportion of transmitted task climate. These data demonstrate that as the educational program was applied, the coachprogressively increased the task climate during the training sessions (Sousa, Cruz, Torregrosa, Vilches, & Viladrich, 2006).It can be concluded that with the application of an educational program focused on the coach's own actions, the climateoriented to task improved in training sessions(AU)


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto , Basquetebol/psicologia , Motivação , Ensino/métodos , Ensino/organização & administração , Esportes/psicologia , Equipamentos Esportivos , Ensaio Clínico , Educação Física e Treinamento/métodos , Educação Física e Treinamento/organização & administração , Educação Física e Treinamento/normas
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