431 research outputs found

    Low Doses of Melatonin to Improve Sleep in Children with ADHD: An Open-Label Trial

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    Objective. Only a few studies assessing the sleep effects of low doses of melatonin (aMT) have been performed in the past, most of them in adults, and only one in subjects with attention-deficit/hyperactivity disorder (ADHD). The aim of this study was to provide evidence of the changes induced by aMT doses as low as 1 mg in the sleep pattern of pediatric patients with ADHD under treatment with methylphenidate (MPH). Methods. Children and adolescents (7–15 years) with ADHD who were receiving extended-release MPH were recruited. A seven-week sleep diary was collected prior to starting a four-week treatment with 1 mg of aMT (30 min before bedtime). Seven-day actigraphic assessments of sleep were performed before and after treatment. Results. Twenty-seven patients (17 males, 62.96%) participated in the study, who had been receiving MPH for 1.57 (1.11) months. A significant increase in sleep duration (TST) was observed after one month of treatment (463 (49) min to 485 (41) min; p < 0.040), with nonsignificant improvements in sleep-onset latency (SOL), nocturnal awakenings, or sleep efficiency. Only minor adverse effects were reported. Conclusion. Low doses of melatonin (1 mg) are able to increase TST in children and adolescents with ADHD receiving treatment with psychostimulants, with an adequate tolerability profile. Further placebo-controlled trials adjusting the time of aMT administration to the individual circadian profile should explore the effects of low doses of this hormone to shorten SOL in this population of patients

    Current Evidence on the Role of the Gut Microbiome in ADHD Pathophysiology and Therapeutic Implications

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    Studies suggest that the bidirectional relationship existent between the gut microbiome (GM) and the central nervous system (CNS), or so-called the microbiome–gut–brain axis (MGBA), is involved in diverse neuropsychiatric diseases in children and adults. In pediatric age, most studies have focused on patients with autism. However, evidence of the role played by the MGBA in attention deficit/hyperactivity disorder (ADHD), the most common neurodevelopmental disorder in childhood, is still scanty and heterogeneous. This review aims to provide the current evidence on the functioning of the MGBA in pediatric patients with ADHD and the specific role of omega-3 polyunsaturated fatty acids (!-3 PUFAs) in this interaction, as well as the potential of the GM as a therapeutic target for ADHD. We will explore: (1) the diverse communication pathways between the GM and the CNS; (2) changes in the GM composition in children and adolescents with ADHD and association with ADHD pathophysiology; (3) influence of the GM on the !-3 PUFA imbalance characteristically found in ADHD; (4) interaction between the GM and circadian rhythm regulation, as sleep disorders are frequently comorbid with ADHD; (5) finally, we will evaluate the most recent studies on the use of probiotics in pediatric patients with ADHD

    Dose-Dependent Effect of Melatonin on BAT Thermogenesis in Zücker Diabetic Fatty Rat: Future Clinical Implications for Obesity

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    Experimental data have revealed that melatonin at high doses reduced obesity and improved metabolic outcomes in experimental models of obesity, mainly by enhancing brown adipose tissue (BAT) thermogenesis. A potential dose-response relationship has yet to be performed to translate these promising findings into potential clinical therapy. This study aimed to assess the effects of different doses of melatonin on interscapular BAT (iBAT) thermogenic capacity in Zücker diabetic fatty (ZDF) rats. At 6 wk of age, male ZDF rats were divided into four groups (n = 4 per group): control and those treated with different doses of melatonin (0.1, 1, and 10 mg/kg of body weight) in their drinking water for 6 wk. Body weight (BW) was significantly decreased at doses of 1 and 10 mg/kg of melatonin, but not at 0.1 mg/kg compared with the control, with a similar rate of BW decrease being reached at the dose of 1 mg/kg (by ~11%) and 10 mg/kg (by ~12%). This effect was associated with a dose-dependent increase in the thermal response to the baseline condition or acute cold challenge in the interscapular area measurable by infrared thermography, with the highest thermal response being recorded at the 10 mg/kg dose. Upon histology, melatonin treatment markedly restored the typical brownish appearance of the tissue and promoted a shift in size distribution toward smaller adipocytes in a dose-dependent fashion, with the most pronounced brownish phenotype being observed at 10 mg/kg of melatonin. As a hallmark of thermogenesis, the protein level of uncoupled protein 1 (UCP1) from immunofluorescence and Western blot analysis increased significantly and dose-dependently at all three doses of melatonin, reaching the highest level at the dose of 10 mg/kg. Likewise, all three doses of melatonin modulated iBAT mitochondrial dynamics by increasing protein expression of the optic atrophy protein type 1 (OPA1) fusion marker and decreasing that of the dynamin-related protein1 (DRP1) fission marker, again dose-dependently, with the highest and lowest expression levels, respectively, being reached at the 10 mg/kg dose. These findings highlight for the first time the relevance of the dose-dependency of melatonin toward BW control and BAT thermogenic activation, which may have potential therapeutic implications for the treatment of obesity. To clinically apply the potential therapeutic of melatonin for obesity, we consider that the effective animal doses that should be extrapolated to obese individuals may be within the dose range of 1 to 10 mg/kg.Ministrio de Ciencia e Innovacion (Spain) SAF2016-79794-REuropean CommissionUniversity of Granada & FEDER Andalucia-UGR 2020 B-CTS-102-UGR2

    Análisis de la implementación de redes eficientes y sostenibles, ejecutada por la empresa distribuidora de energía Disnorte-Dissur para la reducción de las pérdidas eléctrica en el Barrio Quinta Nina, municipio de Managua, departamento de Managua

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    Presenta un proyecto de diseño de redes que muestra los factores fundamentales que se deben de tener en cuenta para la realización de un diseño de redes aéreas protegidas de distribución eléctrica

    Melatonin induces fat browning by transdifferentiation of white adipocytes and de novo differentiation of mesenchymal stem cells

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    This research was partially supported by grant SAF2016-79794R from the Ministerio de Ciencia e Innovacion (Spain), European Regional Development Fund (ERDF), University of Granada and FEDER Funds grant number B-CTS-102-UGR20. The authors thank Antonio Tirado for their technical assistance.The role of melatonin in obesity control is extensively accepted, but its mechanism of action is still unclear. Previously we demonstrated that chronic oral melatonin acts as a brown-fat inducer, driving subcutaneous white adipose tissue (sWAT) into a brown-fat-like function (beige) in obese diabetic rats. However, immunofluorescence characterization of beige depots in sWAT and whether melatonin is a beige-fat inducer by de novo differentiation and/or transdifferentiation of white adipocytes are still undefined. Lean (ZL) and diabetic fatty (ZDF) Zücker rats were subdivided into two groups, control (C) and oral melatonin-supplemented (M, 10 mg kg−1 day−1) for 6 weeks. Mesenchymal stem cells (MSCs) were isolated from both rat inguinal fat and human lipoaspirates followed by adipogenesis assays with or without melatonin (50 nM for 12 h in a 24 h period, 12 h+/12 h−) mimicking the light/dark cycle. Immunofluorescence and western-blot assays showed the partial transdifferentiation of white adipocytes in both ZL and ZDF rats, with increasing thermogenic and beige markers, UCP1 and CITED1 and decreasing white adipocyte marker ASC-1 expression. In addition, melatonin increased UCP1, CITED1, and PGC1- α expression in differentiated adipocytes in both rats and humans. These results demonstrate that melatonin increases brown fat in obese diabetic rats by both adipocyte transdifferentiation and de novo differentiation. Furthermore, it promotes beige MSC adipogenesis in humans. This may contribute to the control of body weight attributed to melatonin and its metabolic benefits in human diabesity.Spanish Government SAF2016-79794REuropean Commission B-CTS-102-UGR20University of Granad

    The preventive and protective role of melatonin in SARS-CoV-2 infection: a retrospective study

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    This study has investigated the protective role of melatonin against SARS-CoV-2 infection. For this purpose, 62 adults were recruited who were in daily relatively high doses of melatonin intaking, with the particularity that they started taking it before the beginning of the COVID-19 pandemic and continued to present. A continuous validation process has been carried out with a series of questionnaires to identify the risk factors, whether they were contacts, were infected, if yes, the level of disease severity, need for treatment, hospitalization, etc. According to the dose of melatonin the individuals took/are taking, they were divided into two groups: a) those taking 20 mg (n = 27) and, b) those taking ≥ 40 mg (n = 32). For statistical analysis, the shi2 test and Fisher's exact test were used. The number of infected subjects with positive PCR was 7 (11.9%). Only one required medication, the rest had a very favorable clinical evolution, mild in three cases and asymptomatic in three others. While in their environment this percentage is 22.05% (chi2 = 2.928; p < 0.087). Melatonin offers a good safety profile, is well tolerated and can play an important role in the different levels of COVID-19 prevention

    Perceptions of Heat Stress, Heat Strain and Mitigation Practices in Wildfire Suppression across Southern Europe and Latin America

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    This study aimed to assess current perceptions of heat stress, heat strain, acclimatisation and recovery practices in wildland fire suppression. A total of 1459 wildfire and structural firefighters, all involved in wildland fire suppression, completed an 18-question survey. Most participants (81.3%) reported heat strain as one of the main risks faced during wildland firefighting. Thermal strain is considered an important risk for health and safety in wildland firefighting. The best-valued heat strain mitigation strategies were those traditionally recommended in wildland fire suppression: (i) an adequate work/rest ratio (79.0%), (ii) acclimatisation (71.6%), (iii) enhancing body ventilation by opening protective clothing or removing helmets or gloves (63.5%), and (iv) drinking water and food supplementation (52.1%). Despite these results, only 22% of the participants reported carrying out acclimatisation in the workplace. The vast majority of the respondents (87.4%) consider active cooling strategies (i.e., ice slurry ingestion, ice vests, etc.) impractical in combating heat strain during wildfire suppression. We identified a gap between knowledge about heat strain, its mitigation strategies and the level of actual implementation of these practices in the workplace. Our results highlight the need to improve heat strain management and implement operational directives for acclimatisation and active cooling interventions

    Associations between self-perceived and desired health-related physical fitness in Spanish children

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    Health-related physical fitness (HRPF) has emerged as an important marker of health among children. It is usually defined as a multidimensional construct consisting of cardiorespiratory endurance; muscular strength and endurance; and flexibility. Currently, health policies are aimed at getting children to increase their HRPF levels. Understanding the relationship between the perceived and the desired levels of fitness can be important to avoid the abandoning of physical activity practice. We analyzed the associations between the self-perceived and the desired health-related physical fitness. A modified version of the self-perceived HRPF questionnaire was completed by 330 children (148 girls, mean age: 10.78 ± 0.67 years, and 182 boys, mean age: 10.82 ± 0.61 years). Fitness was measured through tests selected from the Eurofit battery. The questions regarding desired HRPF showed moderate internal consistency (Cronbach’s α: 0.671) and good test–retest reliability (ICC: 0.761). In general, children shared a desire to improve their self-perceived HRPF. Those who perceived themselves as already being fit were the ones who showed the strongest desire for achieving higher HRPF levels

    Perceptions of Heat Stress, Heat Strain and Mitigation Practices in Wildfire Suppression across Southern Europe and Latin America

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    [EN] This study aimed to assess current perceptions of heat stress, heat strain, acclimatisation and recovery practices in wildland fire suppression. A total of 1459 wildfire and structural firefighters, all involved in wildland fire suppression, completed an 18-question survey. Most participants (81.3%) reported heat strain as one of the main risks faced during wildland firefighting. Thermal strain is considered an important risk for health and safety in wildland firefighting. The best-valued heat strain mitigation strategies were those traditionally recommended in wildland fire suppression: (i) an adequate work/rest ratio (79.0%), (ii) acclimatisation (71.6%), (iii) enhancing body ventilation by opening protective clothing or removing helmets or gloves (63.5%), and (iv) drinking water and food supplementation (52.1%). Despite these results, only 22% of the participants reported carrying out acclimatisation in the workplace. The vast majority of the respondents (87.4%) consider active cooling strategies (i.e., ice slurry ingestion, ice vests, etc.) impractical in combating heat strain during wildfire suppression. We identified a gap between knowledge about heat strain, its mitigation strategies and the level of actual implementation of these practices in the workplace. Our results highlight the need to improve heat strain management and implement operational directives for acclimatisation and active cooling interventions.SIConsejería de Industria, Comercio y Empleo, Junta de Castilla y Leó

    Branding como estrategia de posicionamiento de la marca corporativa

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    El presente trabajo de Seminario de Graduación, es una investigación documental que tiene como tema principal el marketing, que es la herramienta fundamental para la creación de valor para el cliente, y el establecimiento de relaciones provechosas con los consumidores. Busca entender las necesidades y deseos del consumidor, determinar el mercados meta, y luego desarrollar una propuesta de valor que pueda atraer e incrementar la participación del mercado. Como subtema se desarrolla al branding como estrategia de posicionamiento de la marca corporativa, creador de un entorno rentable, diferenciador y único que apoye y empuje la actividad empresarial. El branding debe preceder a las acciones de marketing e imprimir una filosofía a la organización, define con claridad la identidad y razón de ser de sus marcas, logrando así la identificación y preferencia de sus clientes. El branding establece la verdadera diferencia, buscando que las marcas dejen una huella indeleble en la mente y corazones de sus consumidores. En el primer capítulo se aborda generalidades del branding desarrollando acápites fundamentales como la definición del branding, importancia del branding, su historia y evolución. El segundo capítulo se enfoca en mostrar el proceso de construcción de la marca, partiendo de la definición de marca, su importancia, elementos, comunicación, estrategia, función y el proceso de la administración estratégica de la marca. En el tercer capítulo se presenta el proceso de construcción de la imagen e identidad corporativa donde la estrategia de branding es la que juega un papel determinante. Abordamos la definición de branding desde varios puntos de vista, los elementos, componentes, factores y leyes que son inmutables para su debida aplicación, funciones del branding y las estrategias que le agregan valor a la marca corporativa. El presente trabajo es una investigación meramente documental basadas en referencias bibliográficas y páginas web de expertos en la materia, respetando el derecho de autor
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