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1.
Chronobiol Int ; 41(6): 817-828, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38745424

RESUMO

The purpose of this study was to investigate the effects of a novel dietary supplement, including melatonin and magnesium, delivered via coffee pods on sleep quality, resting metabolic rate (RMR), and body composition in individuals with poor sleep quality disturbances. Using a double-blinded, randomized, crossover trial, we recruited 35 participants to a 4-week intervention with both supplements (1.9 mg melatonin + 200 mg elemental magnesium before sleep) and placebo conditions, considering a 7d washout period between treatments. The Pittsburgh Sleep Quality Index (PSQI) questionnaire was applied, RMR (kcal) was measured using indirect calorimetry (canopy ventilated open-circuit system) and body composition was assessed using dual-energy X-ray absorptiometry. Decreases in PSQI and anger - hostility scores, as well as in energy intake and fat mass, were observed (p < 0.05) for both conditions, from baseline to the end of each 4-week intervention. Differences between conditions were also observed for these parameters along with energy spent in activity, number of sedentary breaks, sleep efficiency, latency time, time in bed, total sleep time, awakening time, and movement index (p < 0.05) favouring the supplement condition. However, the final PSQI questionnaire scores still indicated poor sleep quality on average (PSQI > 5), in both conditions, with no changes regarding RMR. A melatonin-magnesium supplement, in a coffee pod format, showed improvements in sleep quality in otherwise healthy individuals with sleep disturbances, however PSQI questionnaire scores still indicated poor quality on average (PSQI > 5).


Assuntos
Composição Corporal , Suplementos Nutricionais , Magnésio , Melatonina , Sono , Humanos , Melatonina/administração & dosagem , Feminino , Masculino , Adulto , Composição Corporal/efeitos dos fármacos , Método Duplo-Cego , Magnésio/administração & dosagem , Sono/efeitos dos fármacos , Sono/fisiologia , Estudos Cross-Over , Pessoa de Meia-Idade , Metabolismo Basal/efeitos dos fármacos , Qualidade do Sono , Inquéritos e Questionários , Ritmo Circadiano/efeitos dos fármacos , Ritmo Circadiano/fisiologia , Adulto Jovem , Transtornos do Sono-Vigília/tratamento farmacológico
2.
Chronobiol Int ; 41(5): 647-657, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38606916

RESUMO

Later chronotypes may be associated with lower diet quality and later timing of energy intake in paediatric age. Period of data collection of these variables may affect these parameters and inter-relationship. We aimed to assess the cross-sectional association of chronotype with a diet quality score (HEI) and caloric midpoint (time of achieving 50% of total daily energy intake), considering summer holidays, using data from the National Food, Nutrition and Physical Activity Survey 2015-2016 for 578 participants (6-14 years of age). Chronotype was estimated by the midpoint of sleep and categorized as Early, Intermediate and Late, using physical activity diaries, while outcomes using two food diaries/24 h recalls. Associations of chronotype with outcomes were assessed by linear regressions adjusted for sex, age, parental education (model 1), BMI, sports practice (model 2), and summer holidays (no/yes) (model 3). In model 2, a Late vs. Early chronotype was negatively associated with HEI (߈ = -0.74; 95% CI: -1.47, -0.07) and positively with caloric midpoint (߈ = 0.35; 95% CI: 0.02, 0.69). However, associations lost significance in model 3. The association between chronotype and dietary habits may be benefit from being studied considering school terms and summer holidays. Future larger prospective studies are needed to clarify the role of summer holidays on this inter-relationship.


Assuntos
Ritmo Circadiano , Dieta , Ingestão de Energia , Férias e Feriados , Estações do Ano , Sono , Humanos , Criança , Feminino , Masculino , Adolescente , Ingestão de Energia/fisiologia , Ritmo Circadiano/fisiologia , Sono/fisiologia , Estudos Transversais , Portugal , Comportamento Alimentar/fisiologia , Exercício Físico/fisiologia , Fatores de Tempo , Cronotipo
3.
Sci Rep ; 13(1): 19473, 2023 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-37945756

RESUMO

Abnormal dopamine neurotransmission is a common trait of some psychiatric diseases, like schizophrenia or bipolar disorder. Excessive dopaminergic tone in subcortical brain regions is associated with psychotic episodes, while reduced prefrontal dopaminergic activity is associated with impaired cognitive performance and reduced motivation, among other symptoms. Inhibitory interneurons expressing the calcium binding protein parvalbumin are particularly affected in both schizophrenia and bipolar disorder, as they set a fine-tuned physiological inhibitory/excitatory balance. Parvalbumin and somatostatin interneuron subtypes, are born from the medial ganglionic eminence and require the sequential expression of specific transcription factors for their specification, such as Nkx6.2. Here, we aimed at characterizing in detail interneuron subtypes derived from Nkx6.2 expressing progenitors by the generation of an Nkx6.2 Cre transgenic mouse line. We show that Nkx6.2 specifies over a third part of the total population of cortical somatostatin interneurons, preferentially at early developmental time points, whereas at late developmental stages, Nkx6.2 expressing progenitors shift to parvalbumin interneuron specification. Dopamine D2 receptor deletion from Nkx6.2 expressing progenitors causes abnormal phenotypes restricted to cognitive, motivation and anxiety domains. Our results show that Nkx6.2 have the potential to specify both somatostatin and parvalbumin interneurons in an opposite timed program and that DRD2 expression is required in Nkx6.2 expressing progenitors to avoid impaired phenotypes commonly associated to the pathophysiology of psychiatric diseases.


Assuntos
Motivação , Parvalbuminas , Animais , Camundongos , Ansiedade/genética , Cognição , Interneurônios/metabolismo , Camundongos Transgênicos , Parvalbuminas/metabolismo , Fenótipo , Receptores de Dopamina D2/genética , Receptores de Dopamina D2/metabolismo , Somatostatina/genética , Somatostatina/metabolismo
4.
J Fungi (Basel) ; 9(8)2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37623608

RESUMO

Candida auris is an opportunistic human pathogen that has rapidly spread to multiple countries and continents and has been associated with a high number of nosocomial outbreaks. Herein, we report the first case of C. auris in Portugal, which was associated with a patient transferred from Angola to an ICU in Portugal for liver transplantation after a SARS-CoV-2 infection. C. auris was isolated during the course of bronchoalveolar lavage, and it was subjected to antifungal susceptibility testing and whole-genome sequence analysis. This isolate presents low susceptibility to azoles and belongs to the genetic clade III with a phylogenetic placement close to African isolates. Although clade III has already been reported in Europe, taking into account the patient's clinical history, we cannot discard the possibility that the patient's colonization/infection occurred in Angola, prior to admission in the Portuguese hospital. Considering that C. auris is a fungal pathogen referenced by WHO as a critical priority, this case reinforces the need for continuous surveillance in a hospital setting.

5.
J Phys Chem A ; 125(38): 8476-8481, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34286990

RESUMO

Reversible electronic energy transfer (homo-FRET) in cyclic multichromophoric systems is studied for sets of n identical fluorophores arranged in regular polygons (triangle, square, pentagon, etc.). A general analytic expression for the anisotropy decay is obtained for a regular polygon of any order, under the assumptions of isotropic interaction and nearest-neighbor FRET. A graphical way of connecting the decay form and polygon geometry based on the Frost circle is also presented. The consequences of the relaxation of these assumptions on the anisotropy decay are also discussed and analyzed in detail for the heptagon.

6.
BMC Geriatr ; 17(1): 256, 2017 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-29089044

RESUMO

BACKGROUND: The older population is a risk group for hypovitaminosis D. The Ultraviolet Index (UVI) can be an indicator of potential for cutaneous synthesis of vitamin D but physiological and other environmental factors also influence vitamin D synthesis and status. Knowledge about vitamin D status in Portuguese older adults is limited. This study aims to explore the association between Ultraviolet Index and serum 25-hidroxyvitamin D3 [25(OH)D] levels accounting for other potential influential factors. METHODS: A cross-sectional study was conducted between December 2015 and June 2016, in 1497 Portuguese older adults (≥ 65 years) within Nutrition UP 65 project. For each participant, serum 25(OH)D was determined and the mean UVI (mUVI) in the respective residence district was calculated for the previous 30 days. Stepwise linear regression analyses were conducted for the following periods of blood collection: between December and June, December and March and April and June. Standardized regression coefficients (Sß) and 95% confidence intervals were calculated. RESULTS: The median 25(OH)D concentration was 35.9 nmol/L. The UVI was independently and positively associated with 25(OH)D in the models for December-June (Sß = 0.244, 95% CI: 0.198; 0.291, P < 0.001) and April-June (Sß = 0.295, 95% CI: 0.299; 0.362, P < 0.001) and independently and negatively associated in December-March period (Sß = -0.149, 95% CI: -0.211; -0.087, P < 0.001). CONCLUSIONS: In this sample with high vitamin D deficiency frequency, the UVI was a predictor of 25(OH)D levels but the direction of the association varied according to the blood collection period. Our results suggest that accounting for the time of year in future research regarding vitamin status and related public health recommendations may be relevant.


Assuntos
Dieta , Estações do Ano , Luz Solar , Raios Ultravioleta , Deficiência de Vitamina D/sangue , Vitamina D/análogos & derivados , Idoso , Estudos Transversais , Suplementos Nutricionais , Feminino , Humanos , Masculino , Estado Nutricional , Portugal , Análise de Regressão , Fatores de Risco , Vitamina D/sangue , Deficiência de Vitamina D/etiologia , Vitaminas/uso terapêutico
7.
Rev Biol Trop ; 60(1): 483-94, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22458241

RESUMO

Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie's fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.


Assuntos
Árvores , Verbenaceae/crescimento & desenvolvimento , Timor-Leste , Verbenaceae/classificação
8.
Rev. biol. trop ; 60(1): 483-494, Mar. 2012. ilus, graf, tab
Artigo em Inglês | LILACS | ID: lil-657795

RESUMO

Teak (Tectona grandis) is one of the most valuable timbers in international trade and an important species for tropical forestry. Teak is found on the island of East Timor but no information is available on teak growth from this region. A pure stand planted in 1940-50 in the North of East Timor and left unmanaged was studied. Fifteen trees were sampled in October-November 2003 and stem discs taken at three height levels of its height (1.7m, 9.5m and 18.7m), and cores were collected at DBH. Transverse surfaces of the discs and cores were polished for ring identification. Core cross sections were first digitized and disc cross sections were observed under the microscope. Three randomly selected radii were analyzed in each disc. Ring width measurement and ring counting were done using image analysis software. The distinction between heartwood and sapwood was performed macroscopically by colour difference, and heartwood radius and sapwood width were measured. The relationship between stem and heartwood radius was studied for each disc and heartwood percentage by radius was determined. Radial ring width curves are presented for the different axial positions within the stem, and ring width variability was analyzed. Growth rates were calculated and age-radius relationships were estimated using cumulative growth curves. Growth rings were large and well defined in the juvenile phase, reflecting the specie’s fast-growing character. The year-to-year variation of ring width showed a similar pattern among trees. Mean ring width ranged between 4.3-7.3mm for the first 20 years and 3.3-5.1mm for 30 to 45 years. Pith eccentricity was evident in the lower part of the stem and ring wedging occurred. On average, heartwood represented 84% of the radius and sapwood contained 6 to 11 rings. The age-related variation of ring width and the occurrence in the lower part of the tree stems of eccentricity and wedging rings, highlights the importance of appropriate stand management, particularly regarding basal density distribution over time, whenever optimized timber production is envisaged.


La madera de teca (Tectona grandis L.f.) es una de las más valiosas en el comercio internacional y una especie importante para la silvicultura tropical. La teca se encuentra en la isla de Timor Leste, pero no existe información disponible sobre su crecimiento en esta región. Se estudió una plantación pura no manejada que fue establecida entre 1940 y 1950 en el Norte de Timor Leste. Entre Octubre- Noviembre 2003 se cosecharon 15 árboles y al tronco se les extrajeron discos a tres niveles de altura (1.7m, 9.5m y 18.7 m), y se recolectaron núcleos a la altura del pecho (DAP). El conteo y la medición de los anillos se realizaron mediante el software de análisis de imagen. La distinción entre el duramen y la albura se realizó macroscópicamente por la diferencia de color, y se midieron el radio del duramen y el ancho de la albura. Para cada disco se estudió la relación entre el tallo y radio del duramen y el porcentaje del duramen. Las curvas de variación del ancho de los anillos se presentan para las diferentes posiciones axiales dentro del tronco y se analizó la variabilidad del ancho de los anillos. Las tasas de crecimiento fueron calculadas y las relaciones de radio con la edad se calcularon usando las curvas de crecimiento acumulado. Los anillos de crecimiento eran grandes y bien definidos en la fase juvenil, lo que refleja el carácter de crecimiento rápido de esta especie. La variación en la anchura de los anillos año a año mostró un patrón similar entre los árboles. La anchura media del anillo osciló entre 4.3-7.3mm para los primeros 20 años y 3.3-5.1mm para los de 30 a 45 años. La excentricidad de la médula fue evidente en la parte inferior del tallo y se observó la formación de anillos sobrepuestos. En promedio, el duramen representó el 84% del radio y la albura mostró entre 6 y 11 anillos. La variación del ancho de los anillos con la edad, la presencia de excentricidad en la parte inferior del árbol y los anillos sobrepuestos pone de relieve la importancia del manejo forestal con particular atención a la distribución de densidad basal en el tiempo, cuando se pretende la producción optimizada de la madera.


Assuntos
Árvores , Verbenaceae/crescimento & desenvolvimento , Timor-Leste , Verbenaceae/classificação
9.
Rev Port Pneumol ; 12(4): 369-74, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16969569

RESUMO

INTRODUCTION: Central nervous system disorders in workers exposed to low frequency noise (LFN, < 500 Hz, including infrasound) were first observed 25 years ago among aircraft technicians. Concurrently, respiratory pathology was identified in these workers, and later reproduced in LFN-exposed animal models. Today vibroacoustic disease (VAD) is defined as the systemic pathology caused by excessive exposure to LFN. The respiratory tract continues to be under heavy scrutiny in both LFN-exposed humans and animal models and has been confirmed as a major target for LFN-induced damage. Given that both the respiratory and central nervous systems were compromised in these workers, it became pertinent to investigate the status of the neurological control of breathing in VAD patients. METHODS: The P- 0.1 value, a measure of the suction pressure developed at the mouth 0.1 seconds after the start of inspiration, depends on the respiratory centres and the autonomic nervous system pathway of the neural control of respiratory function. By rebreathing CO2, (6% in air) normal individuals present an average seven-fold increase in P0.1 (CO2) as compared to basal P- 0.1. Twenty-two male VAD patients (ave. age 50.5 +/- 8.5 years, range: 36-66 years) underwent the P0.1(CO2) index respiratory drive tests, as well as standard pulmonary function tests. Seven individuals (ave. age 42.4 +/-14 years, range: 25- 61 years) with reduced LFN exposure served as controls. RESULTS: Pulmonary function tests were normal in both VAD patients and controls. The P0.1 (CO2) in- dex was below average value in VAD patients (average: 22.9%) while it presented normal values in the control group (average > 60%). DISCUSSION: In the involuntary response to increased PCO2 levels, central chemoreceptors are responsible for 70% of the ventilatory stimulus. In VAD patients, this dysfunction may originate in the brainstem. This is corroborated by the fact that VAD patients register abnormal values for auditory brainstem evoked potentials, and disclose lesions with magnetic resonance imaging. The neurological control of breathing is compromised in VAD patients. The P0.1 (CO2) index may be a useful clinical indicator for VAD diagnosis and follow-up.


Assuntos
Doenças do Sistema Nervoso Central/etiologia , Doenças do Sistema Nervoso Central/fisiopatologia , Ruído Ocupacional/efeitos adversos , Doenças Profissionais/etiologia , Doenças Profissionais/fisiopatologia , Respiração , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Espirometria
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