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1.
Artículo en Inglés | MEDLINE | ID: mdl-38853594

RESUMEN

OBJECTIVE: Moderate-to-vigorous physical activity (MVPA) improves glucose levels; however, whether its timing affects daily glycemic control remains unclear. This study aims to investigate the impact of lifestyle MVPA timing on daily glycemic control in sedentary adults with overweight/obesity and metabolic impairments. METHODS: A total of 186 adults (50% women; age, 46.8 [SD 6.2] years) with overweight/obesity (BMI, 32.9 [SD 3.5] kg/m2) and at least one metabolic impairment participated in this cross-sectional study. MVPA and glucose patterns were simultaneously monitored over a 14-day period using a triaxial accelerometer worn on the nondominant wrist and a continuous glucose-monitoring device, respectively. Each day was classified as "inactive" if no MVPA was accumulated; as "morning," "afternoon," or "evening" if >50% of the MVPA minutes for that day were accumulated between 0600 and 1200, 1200 and 1800, or 1800 and 0000 hours, respectively; or as "mixed" if none of the defined time windows accounted for >50% of the MVPA for that day. RESULTS: Accumulating >50% of total MVPA during the evening was associated with lower 24-h (mean difference [95% CI], -1.26 mg/dL [95% CI: -2.2 to -0.4]), diurnal (-1.10 mg/dL [95% CI: -2.0 to -0.2]), and nocturnal mean glucose levels (-2.16 mg/dL [95% CI: -3.5 to -0.8]) compared with being inactive. This association was stronger in those participants with impaired glucose regulation. The pattern of these associations was similar in both men and women. CONCLUSIONS: These findings suggest that timing of lifestyle MVPA is significant. Specifically, accumulating more MVPA during the evening appears to have a beneficial effect on glucose homeostasis in sedentary adults with overweight/obesity and metabolic impairments.

2.
Nutr Metab Cardiovasc Dis ; 34(1): 177-187, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37949715

RESUMEN

BACKGROUND AND AIMS: To investigate the efficacy and feasibility of three different 8 h time-restricted eating (TRE) schedules (i.e., early, late, and self-selected) compared to each other and to a usual-care (UC) intervention on visceral adipose tissue (VAT) and cardiometabolic health in men and women. METHODS AND RESULTS: Anticipated 208 adults (50% women) aged 30-60 years, with overweight/obesity (25 ≤ BMI<40 kg/m2) and with mild metabolic impairments will be recruited for this parallel-group, multicenter randomized controlled trial. Participants will be randomly allocated (1:1:1:1) to one of four groups for 12 weeks: UC, early TRE, late TRE or self-selected TRE. The UC group will maintain their habitual eating window and receive, as well as the TRE groups, healthy lifestyle education for weight management. The early TRE group will start eating not later than 10:00, and the late TRE group not before 13:00. The self-selected TRE group will select an 8 h eating window before the intervention and maintain it over the intervention. The primary outcome is changes in VAT, whereas secondary outcomes include body composition and cardiometabolic risk factors. CONCLUSION: This study will determine whether the timing of the eating window during TRE impacts its efficacy on VAT, body composition and cardiometabolic risk factors and provide insights about its feasibility.


Asunto(s)
Enfermedades Cardiovasculares , Grasa Intraabdominal , Adulto , Masculino , Humanos , Femenino , Composición Corporal , Factores de Riesgo Cardiometabólico , Escolaridad , Enfermedades Cardiovasculares/diagnóstico , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/prevención & control , Ayuno , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
4.
Eur J Nutr ; 62(5): 2303-2315, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37100891

RESUMEN

PURPOSE: To investigate the association of meal timing with body composition and cardiometabolic risk factors in young adults. METHODS: In this cross-sectional study participated 118 young adults (82 women; 22 ± 2 years old; BMI: 25.1 ± 4.6 kg/m2). Meal timing was determined via three non-consecutive 24-h dietary recalls. Sleep outcomes were objectively assessed using accelerometry. The eating window (time between first and last caloric intake), caloric midpoint (local time at which ≥ 50% of daily calories are consumed), eating jetlag (variability of the eating midpoint between non-working and working days), time from the midsleep point to first food intake, and time from last food intake to midsleep point were calculated. Body composition was determined by DXA. Blood pressure and fasting cardiometabolic risk factors (i.e., triglycerides, total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, and insulin resistance) were measured. RESULTS: Meal timing was not associated with body composition (p > 0.05). The eating window was negatively related to HOMA-IR and cardiometabolic risk score in men (R2 = 0.348, ß = - 0.605; R2 = 0.234, ß = - 0.508; all p ≤ 0.003). The time from midsleep point to first food intake was positively related to HOMA-IR and cardiometabolic risk score in men (R2 = 0.212, ß = 0.485; R2 = 0.228, ß = 0.502; all p = 0.003). These associations remained after adjusting for confounders and multiplicity (all p ≤ 0.011). CONCLUSIONS: Meal timing seems unrelated to body composition in young adults. However, a longer daily eating window and a shorter time from midsleep point to first food intake (i.e., earlier first food intake in a 24 h cycle) are associated with better cardiometabolic health in young men. CLINICAL TRIAL REGISTRATION: NCT02365129 ( https://www. CLINICALTRIALS: gov/ct2/show/NCT02365129?term=ACTIBATE&draw=2&rank=1 ).


Asunto(s)
Factores de Riesgo Cardiometabólico , Enfermedades Cardiovasculares , Adulto , Femenino , Humanos , Masculino , Adulto Joven , Composición Corporal , Enfermedades Cardiovasculares/epidemiología , HDL-Colesterol , Estudios Transversales , Factores de Riesgo
5.
Int J Mol Sci ; 23(23)2022 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-36499035

RESUMEN

Sleep quality plays an important role in the modulation of several aging markers. This influence could be explained by aging-induced hormonal changes. Indeed, poor sleep quality has been associated with the development of several endocrine-related health complications. This study examined the relationship of both subjective and objective sleep quantity and quality, with basal levels of selected plasma anabolic and catabolic hormones in sedentary middle-aged adults. A total of 74 volunteers (52.7% women; aged 53.7 ± 5.1) were recruited for this study. Subjective sleep quality was assessed by the Pittsburgh Sleep Quality Index (PSQI; higher scores indicate worse sleep quality), and objective sleep quality parameters (total sleep time [TST], wake after sleep onset [WASO], and sleep efficiency [SE]) were measured using a wrist-worn accelerometer. Basal levels of plasma dehydroepiandrosterone sulphate (DHEAS), total testosterone, sex hormone binding globulin (SHBG), somatotropin, and cortisol levels, were determined. Free testosterone was calculated from the total testosterone and SHBG levels. No associations of global PSQI score, TST, WASO, and SE with DHEAS, free testosterone, and somatotropin plasma levels were found, neither in men nor in women (all p ≥ 0.05). Global PSQI score was inversely related to cortisol plasma levels in women (p = 0.043). WASO was positively associated with cortisol plasma levels, while SE was negatively associated with cortisol plasma levels in women (all p ≤ 0.027). Sleep quality is not related to levels of plasma anabolic hormones, but to levels of catabolic hormones, in sedentary middle-aged adults. Therefore, these results suggest that potential changes in aging biomarkers associated with sleep disturbances, could be mediated by age-related changes in the catabolic endocrine system.


Asunto(s)
Envejecimiento , Sueño , Persona de Mediana Edad , Adulto , Masculino , Humanos , Femenino , Sulfato de Deshidroepiandrosterona , Testosterona , Hormona del Crecimiento
6.
Metabolites ; 12(9)2022 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-36144186

RESUMEN

The effects of the different electrical frequencies of whole-body electrical stimulation (WB-EMS) on energy expenditure (EE) and the respiratory exchange ratio (RER) remain poorly understood. This study aimed to determine the effects of different WB-EMS electrical frequencies on EE and the RER during supine resting and uphill walking. A total of 10 healthy and recreationally active men (21.6 ± 3.3 years old) participated in the present study. Participants completed two testing sessions in a randomized order. In each session, a variety of impulse frequencies (1 hertz (Hz), 2 Hz, 4 Hz, 6 Hz, 8 Hz, and 10 Hz) were applied in a randomized order, allowing a 10 min passive recovery between them. Oxygen consumption and carbon dioxide production were measured to calculate EE and the RER. All frequencies increased EE at rest (all p ≤ 0.001), with 4 Hz being the frequency producing the highest increase (Δ = 8.89 ± 1.49 kcal/min), as did 6 Hz (Δ = 8.05 ± 1.52 kcal/min) and 8 Hz (Δ = 7.04 ± 2.16 kcal/min). An increment in the RER at rest was observed with 4 Hz, 6 Hz, 8 Hz and 10 Hz (all p ≤ 0.016), but not with 1 Hz and 2 Hz (p ≥ 0.923). During uphill walking, the frequency that elicited the highest increase in EE was 6 Hz (Δ = 4.87 ± 0.84 kcal/min) compared to the unstimulated condition. None of the impulse frequencies altered the RER during uphill walking. WB-EMS increases EE in healthy young men both during resting and uphill walking.

7.
Eur J Appl Physiol ; 122(8): 1863-1874, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35538242

RESUMEN

PURPOSE: This study aimed to investigate the influence of different exercise training modalities on heart rate variability (HRV) in sedentary middle-aged adults; and to study whether changes in health-related outcomes (i.e., body composition and cardiometabolic risk) are associated with those hypothetical HRV changes in sedentary middle-aged adults. METHODS: A total of 66 middle-aged adults (53.6 ± 4.4 years old; 50% women) were enrolled in the FIT-AGEING study. We conducted a 12-week randomized controlled trial. The participants were randomly assigned to 4 groups: (a) a control group (no exercise); (b) a physical activity recommendation from the World Health Organization group (PAR); (c) a high-intensity interval training group (HIIT); and (d) a high-intensity interval training group adding whole-body electromyostimulation (HIIT + EMS). RESULTS: All exercise training modalities induced changes in HRV parameters (all P ≤ 0.001) without statistical differences between them (all P > 0.05). We found associations between changes in body composition and cardiometabolic risk and exercise-related changes in HRV. CONCLUSION: Our results suggest that different exercise interventions (i.e., PAR, HIIT and HIIT + EMS) induced an enhancement of HRV in sedentary middle-aged adults. Our findings support the notion that exercise-related changes in HRV are associated with changes in body composition and cardiometabolic risk after the intervention program CLINICAL TRIAL REGISTRY: NCT03334357 (ClinicalTrials.gov). November 7, 2017 retrospectively registered.


Asunto(s)
Enfermedades Cardiovasculares , Entrenamiento de Intervalos de Alta Intensidad , Adulto , Composición Corporal/fisiología , Ejercicio Físico/fisiología , Femenino , Frecuencia Cardíaca , Entrenamiento de Intervalos de Alta Intensidad/métodos , Humanos , Masculino , Persona de Mediana Edad
8.
Nutrients ; 14(3)2022 Jan 23.
Artículo en Inglés | MEDLINE | ID: mdl-35276847

RESUMEN

This review summarizes the effects of different types of intermittent fasting (IF) on human cardiometabolic health, with a focus on energy metabolism. First, we discuss the coordinated metabolic adaptations (energy expenditure, hormonal changes and macronutrient oxidation) occurring during a 72 h fast. We then discuss studies investigating the effects of IF on cardiometabolic health, energy expenditure and substrate oxidation. Finally, we discuss how IF may be optimized by combining it with exercise. In general, IF regimens improve body composition, ectopic fat, and classic cardiometabolic risk factors, as compared to unrestricted eating, especially in metabolically unhealthy participants. However, it is still unclear whether IF provides additional cardiometabolic benefits as compared to continuous daily caloric restriction (CR). Most studies found no additional benefits, yet some preliminary data suggest that IF regimens may provide cardiometabolic benefits in the absence of weight loss. Finally, although IF and continuous daily CR appear to induce similar changes in energy expenditure, IF regimens may differentially affect substrate oxidation, increasing protein and fat oxidation. Future tightly controlled studies are needed to unravel the underlying mechanisms of IF and its role in cardiometabolic health and energy metabolism.


Asunto(s)
Restricción Calórica , Enfermedades Cardiovasculares , Metabolismo Energético , Ayuno , Enfermedades Cardiovasculares/prevención & control , Humanos , Pérdida de Peso
9.
Biol Sport ; 39(2): 451-461, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-35309538

RESUMEN

It is currently unknown the most effective potentiation protocol to increase maximum strength. Hence, we investigated the separated and combined effects of post-tetanic potentiation (PTP) induced by whole-body electrostimulation (WB-EMS) and post-activation potentiation (PAP) induced by voluntary maximum isometric contractions on maximum isometric strength. Ten trained males were randomly evaluated on four occasions. In session A, maximum isometric strength (split squat) was measured in minutes 1, 4, and 8. In session B, the measurements were taken in minutes 2, 6, and 10. In session C, a WB-EMS protocol was applied to elicit PTP and the measurements were performed in minutes 1, 4, and 8. In session D, the same WB-EMS protocol was applied and the measurements were taken in minutes 2, 6, and 10. No significant differences in maximum isometric strength were observed between: (i) the control and WB-EMS in minutes 1 vs. 1 and 2 vs. 2; (ii) the control and PAP in minutes 1 vs. 4, 1 vs. 8, 2 vs. 6, and 2 vs. 10; and (iii) the PAP and WB-EMS plus PAP in minutes 4 vs. 4, 8 vs. 8, 6 vs. 6, and 10 vs. 10. In contrast, the WB-EMS plus PAP revealed a significant increase of 54% (~450 N) compared to the WB-EMS in minutes 4 and 8 compared to the minute 1 (p < 0.001), but not between minutes 2 vs. 6 and 2 vs. 10. The present results showed that PTP induced by WB-EMS in isolation or combined with PAP induced by voluntary maximum isometric contractions did not produce a significant increase in maximum isometric strength compared to the control and PAP alone, respectively.

10.
Int J Sport Nutr Exerc Metab ; 32(4): 275-284, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35339112

RESUMEN

This study aimed to investigate the effects of different exercise training programs on fasting plasma levels of oxylipins, endocannabinoids (eCBs), and eCBs-like molecules in middle-aged sedentary adults. A 12-week randomized controlled trial was conducted using a parallel group design. Sixty-five middle-aged adults (40-65 years old) were randomly assigned to: (a) no exercise (control group), (b) concurrent training based on international physical activity recommendations (PAR group), (c) high-intensity interval training (HIIT group), and (d) HIIT together with whole-body electromyostimulation (HIIT + EMS group). Plasma levels of oxylipins, eCBs, and eCBs-like molecules were determined in plasma samples before and after the intervention using targeted lipidomics. Body composition was assessed through dual-energy X-ray absorptiometry, and dietary intake through a food frequency questionnaire and three nonconsecutive 24-hr recalls. The physical activity recommendations, HIIT, and HIIT-EMS groups showed decreased plasma levels of omega-6 and omega-3-derived oxylipins, and eCBs and eCBs-like molecules after 12 weeks (all Δ ≤ -0.12; all p < .05). Importantly, after Bonferroni post hoc corrections, the differences in plasma levels of omega-6 and omega-3 oxylipins were not statistically significant compared with the control group (all p > .05). However, after post hoc corrections, plasma levels of anandamide and oleoylethanolamide were increased in the physical activity recommendations group compared with the control group (anandamide: Δ = 0.05 vs. -0.09; oleoylethanolamide: Δ = -0.12 vs. 0.013, all p ≤ .049). In conclusion, this study reports that a 12-week exercise training intervention, independent of the modality applied, does not modify fasting plasma levels of omega-6 and omega-3 oxylipins, eCBs, and eCBs-like molecules in middle-aged sedentary adults.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Oxilipinas , Adulto , Anciano , Endocannabinoides , Ejercicio Físico/fisiología , Ayuno , Humanos , Persona de Mediana Edad
11.
Materials (Basel) ; 14(12)2021 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-34207797

RESUMEN

Fs-laser induced element redistribution (FLIER) has been a subject of intensive research in recent years. Its application to various types of glasses has already resulted in the production of efficient optical waveguides, tappers, amplifiers and lasers. Most of the work reported on FLIER-based waveguides refers to structures produced by the cross-migration of alkali (Na, K) and lanthanides (mostly La). The latter elements act as refractive index carrying elements. Herein, we report the production of Ba-based, FLIER-waveguides in phosphate glass with an index contrast > 10-2. Phosphate glasses modified with the same amount of Na2O and K2O, and variable amounts of BaO and/or La2O3 were used to produce the FLIER-waveguides with Ba and or La acting as index carriers. Ba-only modified glasses show a waveguide writing threshold and light guiding performance comparable to that of La-based structures. However, mixed Ba-La glasses show a much higher element migration threshold, and much smaller compositionally modified regions. This behavior is consistent with a competition effect in the cross-migration of both elements (Ba and La) against the alkalis. Such an effect can be applied to inhibit undesired element redistribution effects in fs-laser processing applications in multicomponent glasses.

12.
Nanoscale ; 13(28): 12271-12278, 2021 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-34241608

RESUMEN

We observe the extraction of carriers excited between two types of bands in the perovskite oxide, Sr-deficient strontium niobate (Sr0.9NbO3). Sr0.9NbO3 exhibits metallic behaviour and high conductivity, whilst also displaying broad absorption across the ultraviolet, visible, and near-infrared spectral regions, making it an attractive material for solar energy conversion. Furthermore, the optoelectronic properties of strontium niobate can easily be tuned by varying the Sr fraction or through doping. Sr-deficient strontium niobate exhibits a split conduction band, which enables two types of optical transitions: intraband and interband. However, whether such carriers can be extracted from an unusual material as such remains unproven. In this report, we have overcome the immense challenge of photocarrier extraction by fabricating an extremely thin absorber layer of Sr0.9NbO3 nanoparticles. These findings open up great opportunities to harvest a very broad solar spectral absorption range with reduced recombination losses.

13.
Scand J Med Sci Sports ; 31(9): 1722-1744, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34022085

RESUMEN

To determine the acute effect of a single high-intensity interval training (HIIT) session on testosterone and cortisol levels in healthy individuals, a systematic search of studies was conducted in MEDLINE and Web of Science databases from inception to February 2020. Meta-analyses were performed to establish the acute effect of HIIT on testosterone and cortisol levels immediately after a single HIIT session; after 30 min and 60 min (primary outcomes); and after 120 min, 180 min, and 24 h (secondary outcomes, only for pre-post intervention groups). Potential effect-size modifiers were assessed by meta-regression analyses and analyses of variance. Study quality was assessed using the Cochrane's risk of bias tool and the Physiotherapy Evidence Database scale. The meta-analyses of 10 controlled studies (213 participants) and 50 pre-post intervention groups (677 participants) revealed a significant increase in testosterone immediately after a single HIIT session (d = 0.92 and 0.52, respectively), which disappeared after 30 min (d = 0.18 and -0.04), and returned to baseline values after 60 min (d = -0.37 and -0.16). Significant increases of cortisol were found immediately after (d = 2.17 and 0.64), after 30 min (d = 1.62 and 0.67) and 60 min (d = 1.32 and 0.27). Testosterone and cortisol levels decreased significantly after 120 min (d = -0.48 and -0.95, respectively) and 180 min (d = -0.29 and -1.08), and returned to baseline values after 24 h (d = 0.14 and -0.02). HIIT components and participant's characteristics seem to moderate the effect sizes. In conclusion, testosterone and cortisol increase immediately after a single HIIT session, then drop below baseline levels, and finally return to baseline values after 24 h. This meta-analysis provides a better understanding of the acute endocrine response to a single HIIT session, which would certainly be valuable for both clinicians and coaches in the prescription of exercise programs to improve health and performance. Testosterone and cortisol may be used as sensitive biomarkers to monitor the anabolic and catabolic response to HIIT.


Asunto(s)
Entrenamiento de Intervalos de Alta Intensidad , Hidrocortisona/sangre , Testosterona/sangre , Adolescente , Adulto , Anciano , Sesgo , Biomarcadores/sangre , Femenino , Humanos , Masculino , Persona de Mediana Edad , Acondicionamiento Físico Humano/fisiología , Análisis de Regresión , Factores de Tiempo , Adulto Joven
14.
Sci Rep ; 11(1): 8390, 2021 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-33863947

RESUMEN

Here in, the fs-laser induced thermophoretic writing of microstructures in ad-hoc compositionally designed silicate glasses and their application as infrared optical waveguides is reported. The glass modification mechanism mimics the elemental thermal diffusion occurring in basaltic liquids at the Earth's mantle, but in a much shorter time scale (108 times faster) and over a well-defined micrometric volume. The precise addition of BaO, Na2O and K2O to the silicate glass enables the creation of positive refractive index contrast upon fs-laser irradiation. The influence of the focal volume and the induced temperature gradient is thoroughly analyzed, leading to a variety of structures with refractive index contrasts as high as 2.5 × 10-2. Two independent methods, namely near field measurements and electronic polarizability analysis, confirm the magnitude of the refractive index on the modified regions. Additionally, the functionality of the microstructures as waveguides is further optimized by lowering their propagation losses, enabling their implementation in a wide range of photonic devices.

15.
Eur J Appl Physiol ; 121(8): 2193-2206, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33890158

RESUMEN

PURPOSE: Physical inactivity and ageing are associated with imbalances in anabolic/catabolic steroid hormones, jeopardizing health. We investigated the effects of three types of training on plasma steroid hormone levels in physically inactive, middle-aged adults. METHODS: A 12-week randomized controlled trial was performed with a parallel-group design. A total of 67 (36 women) middle-aged adults (45-65 years old) were randomly assigned to (1) no exercise (control), (2) concurrent training based on the international physical activity recommendations (PAR), (3) high-intensity interval training (HIIT), or (4) HIIT plus whole-body electromyostimulation (HIIT + EMS). The training volume in the PAR group was 150 min/week at 60-65% of the heart rate reserve for aerobic training and ~ 60 min/week at 40-50% of the one-repetition maximum for resistance training. The training volume in the HIIT and HIIT + EMS groups was 40-65 min/week at > 95% of the maximum oxygen uptake in long interval sessions, and > 120% of the maximum oxygen uptake in short interval sessions. RESULTS: Compared to the control group, dehydroepiandrosterone sulfate increased in the PAR, HIIT, and HIIT + EMS groups (~ 14%, ~ 14%, and ~ 20%, respectively; all P < 0.01). Cortisol decreased in the PAR, HIIT, and HIIT + EMS groups (~ - 17%, ~ - 10%, and ~ - 23%, respectively; all P ≤ 0.05). Testosterone increased in the HIIT and HIIT + EMS groups (~ 28%, and ~ 16%, respectively; all P ≤ 0.01). Free testosterone increased in the HIIT and HIIT + EMS groups (~ 30% and ~ 18% respectively; all P ≤ 0.01). No significant increase in sex hormone-binding globulin was observed (P = 0.869). CONCLUSION: Our findings suggest that HIIT, with or without whole-body EMS, can significantly enhance steroid hormones status in previously physically inactive middle-aged adults. The PAR program led to slight improvements than the HIIT and HIIT + EMS groups despite the application of a higher training volume. CLINICAL TRIAL REGISTRY: NCT03334357 (ClinicalTrials.gov). November 7, 2017 retrospectively registered.


Asunto(s)
Deshidroepiandrosterona/sangre , Ejercicio Físico , Hidrocortisona/sangre , Conducta Sedentaria , Testosterona/sangre , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Consumo de Oxígeno/fisiología
17.
Front Chem ; 8: 520, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32626693

RESUMEN

The large area scalable fabrication of supported porous metal and metal oxide nanomaterials is acknowledged as one of the greatest challenges for their eventual implementation in on-device applications. In this work, we will present a comprehensive revision and the latest results regarding the pioneering use of commercially available metal phthalocyanines and porphyrins as solid precursors for the plasma-assisted deposition of porous metal and metal oxide films and three-dimensional nanostructures (hierarchical nanowires and nanotubes). The most advanced features of this method relay on its ample general character from the point of view of the porous material composition and microstructure, mild deposition and processing temperature and energy constrictions and, finally, its straightforward compatibility with the direct deposition of the porous nanomaterials on processable substrates and device-architectures. Thus, taking advantage of the variety in the composition of commercially available metal porphyrins and phthalocyanines, we present the development of metal and metal oxides layers including Pt, CuO, Fe2O3, TiO2, and ZnO with morphologies ranging from nanoparticles to nanocolumnar films. In addition, we combine this method with the fabrication by low-pressure vapor transport of single-crystalline organic nanowires for the formation of hierarchical hybrid organic@metal/metal-oxide and @metal/metal-oxide nanotubes. We carry out a thorough characterization of the films and nanowires using SEM, TEM, FIB 3D, and electron tomography. The latest two techniques are revealed as critical for the elucidation of the inner porosity of the layers.

18.
J Neurochem ; 155(5): 559-576, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32379343

RESUMEN

Lipotoxicity (LTx) leads to cellular dysfunction and cell death and has been proposed to be an underlying process during traumatic and hypoxic injuries and neurodegenerative conditions in the nervous system. This study examines cellular mechanisms responsible for docosahexaenoic acid (DHA 22:6 n-3) protection in nerve growth factor-differentiated pheochromocytoma (NGFDPC12) cells from palmitic acid (PAM)-mediated lipotoxicity (PAM-LTx). NGFDPC12 cells exposed to PAM show a significant lipotoxicity demonstrated by a robust loss of cell viability, apoptosis, and increased HIF-1α and BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 gene expression. Treatment of NGFDPC12 cells undergoing PAM-LTx with the pan-caspase inhibitor ZVAD did not protect, but shifted the process from apoptosis to necroptosis. This shift in cell death mechanism was evident by the appearance of the signature necroptotic Topo I protein cleavage fragments, phosphorylation of mixed lineage kinase domain-like, and inhibition with necrostatin-1. Cultures exposed to PAM and co-treated with necrostatin-1 (necroptosis inhibitor) and rapamycin (autophagy promoter), showed a significant protection against PAM-LTx compared to necrostatin-1 alone. In addition, co-treatment with DHA, as well as 20:5 n-3, 20:4 n-6, and 22:5 n-3, in the presence of PAM protected NGFDPC12 cells against LTx. DHA-induced neuroprotection includes restoring normal levels of HIF-1α and BCL2/adenovirus E1B 19 kDa protein-interacting protein 3 transcripts and caspase 8 and caspase 3 activity, phosphorylation of beclin-1, de-phosphorylation of mixed lineage kinase domain-like, increase in LC3-II, and up-regulation of Atg7 and Atg12 genes, suggesting activation of autophagy and inhibition of necroptosis. Furthermore, DHA-induced protection was suppressed by the lysosomotropic agent chloroquine, an inhibitor of autophagy. We conclude that DHA elicits neuroprotection by regulating multiple cell death pathways including enhancement of autophagy and inhibiting apoptosis and necroptosis.


Asunto(s)
Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Ácidos Docosahexaenoicos/farmacología , Factor de Crecimiento Nervioso/farmacología , Ácido Palmítico/toxicidad , Animales , Apoptosis/fisiología , Autofagia/fisiología , Diferenciación Celular/fisiología , Metabolismo de los Lípidos/efectos de los fármacos , Metabolismo de los Lípidos/fisiología , Células PC12 , Ratas , Especies Reactivas de Oxígeno/metabolismo
19.
J Int Soc Sports Nutr ; 17(1): 29, 2020 May 27.
Artículo en Inglés | MEDLINE | ID: mdl-32460793

RESUMEN

BACKGROUND: High-intensity interval training (HIIT) is an effective approach to improve physical fitness, but consuming beer, which is a regular practice in many physically active individuals, may interfere with these effects. The purposes of this study were to investigate the effects of a 10-week (2 days/week) HIIT program on cardiorespiratory fitness, muscle strength and power parameters, and also to assess the possible influence on them of a moderate consumption of beer (at least from Monday to Friday) or its alcohol equivalent. METHODS: Young (24 ± 6 years old) healthy adults (n = 73, 35 females) were allocated to five groups. Four groups participated in the HIIT intervention program while the fifth group was a control Non-Training group (n = 15). Participants in the training groups chose whether they preferred receiving alcohol or alcohol-free beverages. Those choosing alcohol were randomized to either beer or ethanol intake: (i) T-Beer group (alcohol beer, 5.4%; n = 13) or (ii) T-Ethanol (sparkling water with vodka, 5.4%; n = 14). Those choosing alcohol-free intake were randomized to (iii) T-Water group (sparkling water, 0.0%; n = 16), or (iv) T-0.0Beer group (alcohol-free beer, 0.0%; n = 15). Men ingested 330 ml of the beverage at lunch and 330 ml at dinner; women ingested 330 ml at dinner. Before and after the intervention, maximal oxygen uptake in absolute and relative terms (VO2max.), maximal heart rate, total test duration, hand grip strength and four types of vertical jumps were measured. RESULTS: HIIT induced significant improvements in absolute and relative values of VO2max, and total test duration (all p < 0.05) in all the training groups; also, clinical improvements were found in hand grip strength. These positive effects were not influenced by the regular intake of beer or alcohol. No changes in the vertical jumps occurred in any of the groups. CONCLUSIONS: A moderate beer or alcohol intake does not mitigate the positive effect of a 10-week HIIT on physical fitness in young healthy adults. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT03660579. Registered 20 September 2018. Retrospectively registered.


Asunto(s)
Bebidas Alcohólicas , Cerveza , Capacidad Cardiovascular , Entrenamiento de Intervalos de Alta Intensidad/métodos , Fuerza Muscular , Aptitud Física , Adolescente , Adulto , Femenino , Humanos , Masculino , Fenómenos Fisiológicos en la Nutrición Deportiva , Adulto Joven
20.
Faraday Discuss ; 222(0): 390-404, 2020 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-32133465

RESUMEN

The relationship between the crystallization process and opto-electronic properties of silicon quantum dots (Si QDs) synthesized by atmospheric pressure plasmas (APPs) is studied in this work. The synthesis of Si QDs is carried out by flowing silane as a gas precursor in a plasma confined to a submillimeter space. Experimental conditions are adjusted to propitiate the crystallization of the Si QDs and produce QDs with both amorphous and crystalline character. In all cases, the Si QDs present a well-defined mean particle size in the range of 1.5-5.5 nm. Si QDs present optical bandgaps between 2.3 eV and 2.5 eV, which are affected by quantum confinement. Plasma parameters evaluated using optical emission spectroscopy are then used as inputs for a collisional plasma model, whose calculations yield the surface temperature of the Si QDs within the plasma, justifying the crystallization behavior under certain experimental conditions. We measure the ultraviolet-visible optical properties and electronic properties through various techniques, build an energy level diagram for the valence electrons region as a function of the crystallinity of the QDs, and finally discuss the integration of these as active layers of all-inorganic solar cells.

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