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1.
Front Nutr ; 10: 1213105, 2023.
Article in English | MEDLINE | ID: mdl-37766731

ABSTRACT

Introduction: Beta-alanine is a non-essential amino acid that has been a focus of increasing research by its role as ergogenic aid to improve muscle performance. Methods: A randomized, double-blind and controlled trial was conducted to determine the effect of a nutritional supplement of a sustained-release formulation of ß-alanine in recreational trained men. The active product was an innovative sustained-release ß-alanine microgranules powder blend, administered at high doses (15 g/day) divided into 3 intakes during 30 days. There were 10 participants in the experimental group and 9 in the placebo group, with a mean age of 22.5 ± 3.3 years. Participants were testing at baseline and at the end of study. Results: In the ß-alanine group, there were statistically increases in serum triglycerides, LDL-cholesterol, and urea nitrogen at the end of the study as compared with baseline, although there were no differences with the control group. The occurrence of paresthesia, described above all as tickling, was the majority but presented VAS score less than 3/10 in almost all subjects. Discussion: More studies are required to evaluate the changes in blood parameters that can be caused by high intake of ß-alanine during a long period of time. Clinical trial registration: ClinicalTrials.gov, identifier (NCT05334121).

2.
Polymers (Basel) ; 15(12)2023 Jun 16.
Article in English | MEDLINE | ID: mdl-37376351

ABSTRACT

Nowadays, there exists a huge interest in producing innovative, high-performance, biofunctional, and cost-efficient electrospun biomaterials based on the association of biocompatible polymers with bioactive molecules. Such materials are well-known to be promising candidates for three-dimensional biomimetic systems for wound healing applications because they can mimic the native skin microenvironment; however, many open questions such as the interaction mechanism between the skin and the wound dressing material remain unclear. Recently, several biomolecules were intended for use in combination with poly(vinyl alcohol) (PVA) fiber mats to improve their biological response; nevertheless, retinol, an important biomolecule, has not been combined yet with PVA to produce tailored and biofunctional fiber mats. Based on the abovementioned concept, the present work reported the fabrication of retinol-loaded PVA electrospun fiber mats (RPFM) with a variable content of retinol (0 ≤ Ret ≤ 25 wt.%), and their physical-chemical and biological characterization. SEM results showed that fiber mats exhibited diameters distribution ranging from 150 to 225 nm and their mechanical properties were affected with the increasing of retinol concentrations. In addition, fiber mats were able to release up to 87% of the retinol depending on both the time and the initial content of retinol. The cell culture results using primary mesenchymal stem cell cultures proved the biocompatibility of RPFM as confirmed by their effects on cytotoxicity (low level) and proliferation (high rate) in a dose-dependent manner. Moreover, the wound healing assay suggested that the optimal RPFM with retinol content of 6.25 wt.% (RPFM-1) enhanced the cell migratory activity without altering its morphology. Accordingly, it is demonstrated that the fabricated RPFM with retinol content below the threshold 0 ≤ Ret ≤ 6.25 wt.% would be an appropriate system for skin regenerative application.

3.
Cells ; 11(19)2022 09 26.
Article in English | MEDLINE | ID: mdl-36230954

ABSTRACT

Hydroxyapatite (HA) is a hard mineral component of mineralized tissues, mainly composed of calcium and phosphate. Due to its bioavailability, HA is potentially used for the repair and regeneration of mineralized tissues. For this purpose, the properties of HA are significantly improved by adding natural and synthetic materials. In this sense, the germanium (Ge) mineral was loaded in HA biomaterial by cold isostatic pressure for the first time and characterization and biocompatibility using bone marrow mesenchymal stem cells (BM-MSCs) were investigated. The addition of Ge at 5% improved the solubility (3.32%), stiffness (18.34 MPa), water holding (31.27%) and biodegradation (21.87%) properties of HA, compared to control. Compared to all composite biomaterials, the drug-releasing behavior of HA-3% Ge was higher at pH 1 and 3 and the maximum drug release was obtained at pH 7 and 9 with HA-5% Ge biomaterials. Among the different mediums tested, the DMEM-medium showed a higher drug release rate, especially at 60 min. HA-Ge biomaterials showed better protein adhesion and apatite layer formation, which ultimately proves the compatibility in BM-MSCs culture. Except for higher concentrations of HA (5 and 10 mg/mL), the different concentrations of Ge and HA and wells coated with 1% of HA-1% Ge had higher BM-MSCs growth than control. All these findings concluded that the fabricated HA biomaterials loaded with Ge could be the potential biomaterial for culturing mammalian cells towards mineralized tissue repair and regeneration.


Subject(s)
Germanium , Mesenchymal Stem Cells , Animals , Biocompatible Materials/chemistry , Bone Regeneration , Calcium/metabolism , Durapatite/pharmacology , Germanium/metabolism , Germanium/pharmacology , Mammals , Mesenchymal Stem Cells/metabolism , Osteogenesis , Tissue Scaffolds/chemistry , Water/metabolism
4.
Front Psychol ; 11: 596961, 2020.
Article in English | MEDLINE | ID: mdl-33178090

ABSTRACT

Technology is being used by individuals of all ages; young children show a high tendency of problematic use of devices such as smartphones. This study aimed to identify different profiles that vary in conflicts related to problematic mobile phone use and maladaptive communication and emotional patterns. Therefore, we examined whether there are significant differences in bullying and cyberbullying among teenagers who have a problem utilizing mobile phones. The study participants were 810 students of Compulsory Secondary Education (M = 13.99, SD = 1.32), with 52.2% being girls. Questionnaires on school violence and experiences related to mobile phones were administered. The latent profile analysis identified three different types of problematic mobile phone use: (a) low levels of conflict was associated with mobile phone abuse and low levels of communication and emotional use; (b) moderate levels of conflict was associated with mobile phone abuse and moderate levels of communication and emotional use; and (c) high levels of conflict was associated with mobile phone abuse and high levels of communication and emotional use. The study results highlight significant differences in the manifestations of school violence between the profiles. Finally, this study's findings form the basis for the development of education programs to prevent mobile phone abuse and school violence and therefore academic adjustment.

5.
Invest Ophthalmol Vis Sci ; 58(13): 5819-5826, 2017 11 01.
Article in English | MEDLINE | ID: mdl-29131901

ABSTRACT

Purpose: To compare thicknesses of intraretinal layers segmented by spectral-domain optical coherence tomography (SD-OCT) between autism spectrum disorder (ASD) and neurotypical (NT) individuals. Methods: We performed 2 scans on 108 eyes from 54 participants (27 high-functioning ASD and 27 age- and sex-matched NT subjects): macular fast volume and peripapillary retinal nerve fiber layer (pRNFL). Macula was automatically segmented. The mean foveal and macular thickness of nine different layers and the thickness of nine pRNFL sectors were considered. Data from the right and left eyes were averaged for each participant. The results were compared between the ASD and NT groups. Associations between the Kaufman brief intelligence test (K-BIT), head circumference and SD-OCT results were also investigated in ASD individuals. Results: ASD subjects showed greater foveal thickness at total retina, total inner retina, inner plexiform and inner nuclear layers, and greater macular thickness at total retina and total inner retina. Inferior, nasal inferior and temporal inferior sectors of pRNFL were also thicker in the ASD participants than in the controls (P < 0.05, unpaired t-test). Significant correlations were found between some K-BIT results and temporal inferior and inferior pRNFL thicknesses in the ASD group (P < 0.05, Spearman's rank correlation). No associations were seen between head circumference and OCT parameters. Conclusions: There are intraretinal thickenings at different locations in ASD subjects when compared to NT controls. This fact should be taken into account when interpreting SD-OCT examinations in ASD individuals. Plus, some pRNFL thicknesses present positive correlations with scores of cognitive status in ASD.


Subject(s)
Autism Spectrum Disorder/pathology , Fovea Centralis/pathology , Macula Lutea/pathology , Nerve Fibers/pathology , Optic Disk/pathology , Retinal Ganglion Cells/pathology , Adolescent , Child , Cross-Sectional Studies , Female , Humans , Intelligence Tests , Male , Prospective Studies , Tomography, Optical Coherence , Young Adult
6.
J Environ Manage ; 196: 560-568, 2017 Jul 01.
Article in English | MEDLINE | ID: mdl-28351822

ABSTRACT

Thermochemical valorisation processes that allow energy to be recovered from sewage sludge, such as pyrolysis and gasification, have demonstrated great potential as convenient alternatives to conventional sewage sludge disposal technologies. Moreover, these processes may benefit from CO2 recycling. Today, the scaling up of these technologies requires an advanced knowledge of the reactivity of sewage sludge and the characteristics of the products, specific to the thermochemical process. In this study the behaviour of sewage sludge during thermochemical conversion, under different atmospheres (N2, CO2 and air), was studied, using TGA-FTIR, in order to understand the effects of different atmospheric gases on the kinetics of degradation and on the gaseous products. The different steps observed during the solid degradation were related with the production of different gaseous compounds. A higher oxidative degree of the atmosphere surrounding the sample resulted in higher reaction rates and a shift of the degradation mechanisms to lower temperatures, especially for the mechanisms taking place at temperatures above 400 °C. Finally, a multiple first-order reaction model was proposed to compare the kinetic parameters obtained under different atmospheres. Overall, the highest activation energies were obtained for combustion. This work proves that CO2, an intermediate oxidative atmosphere between N2 and air, results in an intermediate behaviour (intermediate peaks in the derivative thermogravimetric curves and intermediate activation energies) during the thermochemical decomposition of sewage sludge. Overall, it can be concluded that the kinetics of these different processes require a different approach for their scaling up and specific consideration of their characteristic reaction temperatures and rates should be evaluated.


Subject(s)
Atmosphere , Sewage , Gases , Kinetics , Temperature
7.
J Hazard Mater ; 191(1-3): 219-27, 2011 Jul 15.
Article in English | MEDLINE | ID: mdl-21592652

ABSTRACT

Gasification of sewage sludge produces combustible gases as well as tar and a solid residue as by-products. This must be taken into account when determining the optimal thermal conditions for the gasification process. In this study, the influence of temperature, heating atmosphere and residence time on the characteristics of the gasified sewage sludge residues is investigated. ICP-AES analyses reveal that the major chemical elements in the char residues are phosphorus, calcium, iron and silicon. Heavy metals such as copper, zinc, chromium, nickel and lead are also present at relatively high levels - from 50 to more than 1000 mg/kg of dry matter. The major mineral phases' identification - before and after heating - as well as their morphology and approximate chemistry (XRD and SEM-EDX) demonstrate that a number of transformations take place during gasification. These are influenced by the reactor's temperature and the oxidative degree of its internal atmosphere. The copper-, zinc- and chromium-bearing phases are studied using chemometric tools, showing that the distribution of those metals among the mineral phases is considerably different. Finally, batch-leaching tests reveal that metals retained in the residue are significantly stabilized after thermal treatment to a higher or lower extent, depending on the thermal conditions applied.


Subject(s)
Gases/chemistry , Minerals/chemistry , Sewage/chemistry , Microscopy, Electron, Scanning , X-Ray Diffraction
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