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1.
Child Dev ; 95(2): 544-558, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37800868

RESUMO

This study aimed to determine the effects of the Active Early Learning (AEL) childcare center-based physical activity intervention on early childhood executive function and expressive vocabulary via a randomized controlled trial. Three-hundred-and-fourteen preschool children (134 girls) aged 3-5 years from 15 childcare centers were randomly assigned to the intervention (8 centers; n = 170 children) or control group (7 centers, n = 144 children) in May 2019. Participants were mostly Australian (85%) and from slightly higher areas of socio-economic status than the Australian average. There was an AEL intervention effect on inhibition (ß = 0.5, p = .033, d = 0.29) and expressive vocabulary (ß = 1.97, p = .001, d = 0.24). Integration of the AEL physical activity intervention into the daily childcare routine was effective in enhancing children's executive function and expressive language development.


Assuntos
Creches , Função Executiva , Feminino , Criança , Humanos , Pré-Escolar , Função Executiva/fisiologia , Austrália , Desenvolvimento da Linguagem , Exercício Físico
2.
Org Biomol Chem ; 21(38): 7717-7723, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37565617

RESUMO

We report on a convenient synthetic route to rapidly access a new photo-responsive ortho-azobenzene/2,6-pyridyldicarboxamide heterofoldamer. The adoption of a stable helical conformation has been established for this scaffold in both the solid state and in solution using single crystal X-ray diffraction and circular dichroism (CD) spectroscopy respectively. Reversible control over the stimuli-driven structural re-ordering of the supramolecular scaffold, from a stable helical conformation under non-irradiative conditions, to a less well-ordered state under irradiative conditions, has been identified. The robust nature of the responsive, conformational, molecular switching behaviour has been determined using UV/Vis, 1H NMR and CD spectroscopy. Minimal loss in the efficiency of the stimuli-driven, structural re-ordering processes of the foldamer scaffold is observed, even upon multiple cyclic treatments with irradiative/non-irradiative conditions.

3.
Proc Natl Acad Sci U S A ; 117(37): 22858-22865, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32868426

RESUMO

Generality in understanding biodiversity responses to climate change has been hampered by substantial variation in the rates and even directions of response to a given change in climate. We propose that such context dependencies can be clarified by rescaling climate gradients in terms of the underlying biological processes, with biotic interactions as a particularly important process. We tested this rescaling approach in a replicated field experiment where entire montane grassland communities were transplanted in the direction of expected temperature and/or precipitation change. In line with earlier work, we found considerable variation across sites in community dynamics in response to climate change. However, these complex context dependencies could be substantially reduced or eliminated by rescaling climate drivers in terms of proxies of plant-plant interactions. Specifically, bryophytes limited colonization by new species into local communities, whereas the cover of those colonists, along with bryophytes, were the primary drivers of local extinctions. These specific interactions are relatively understudied, suggesting important directions for future work in similar systems. More generally, the success of our approach in explaining and simplifying landscape-level variation in climate change responses suggests that developing and testing proxies for relevant underlying processes could be a fruitful direction for building more general models of biodiversity response to climate change.


Assuntos
Biodiversidade , Mudança Climática , Ecossistema , Pradaria , Plantas , Temperatura
4.
Am J Physiol Regul Integr Comp Physiol ; 323(2): R161-R168, 2022 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-35670483

RESUMO

Both adult females and children have been reported to have a lower sweating capacity and thus reduced evaporative heat loss potential that may increase their susceptibility to exertional hyperthermia in the heat. Compared with males, females have a lower maximal sweat rate and thus a theoretically lower maximum skin wettedness due to a lower sweat output per gland. Similarly, children have been suggested to be disadvantaged in high ambient temperatures due to a lower sweat production and therefore reduced evaporative capacity, despite modifications of heat transfer due to physical attributes and possible evaporative efficiency. The reported reductions in the sudomotor activity of females and children suggest a lower sweating capacity in girls. However, because of the complexities of isolating sex and maturation from the confounding effects of morphological differences (e.g., body surface area-to-mass ratio) and metabolic heat production, limited evidence exists supporting whether children, and, more specifically, girls are at a thermoregulatory disadvantage. Furthermore, a limited number of child-adult comparison studies involve females and very few studies have directly compared regional and whole body sudomotor activity between boys and girls. This minireview highlights the exercise-induced sudomotor response of females and children, summarizes previous research investigating the sudomotor response to exercise in girls, and suggests important areas for further research.


Assuntos
Temperatura Corporal , Transtornos de Estresse por Calor , Adulto , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Feminino , Resposta ao Choque Térmico , Temperatura Alta , Humanos , Masculino , Sudorese
5.
Int J Obes (Lond) ; 45(11): 2506-2510, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34408256

RESUMO

BACKGROUND/OBJECTIVES: Body mass index (BMI, body mass/height2) is biased toward height in children. Here we investigate how change in population height affected change in BMI-based estimates of the prevalence of overweight and obesity in Australian children. SUBJECTS/METHODS: Height, weight, and percent body fat (%BF) were measured at ages 8, 10, and 12 years (1855 sets of measures). Age-specific relationships between BMI and height were derived, adjusting for %BF, to estimate the degree of height bias inherent in BMI. Then, from cross-sectional measurements recorded in 1985 (N = 2388) and 1995 (N = 2148) in 8, 10, and 12 year olds, changes in overweight/obesity prevalences were calculated before and after accounting for the BMI-height bias. RESULTS: Estimates of the effect of height on BMI following adjustment for %BF were similar across age groups and all were significant at p < 0.001. Referring to 12 year olds, at the same %BF for a 1% increase in height there was 0.77% (95% CI 0.55, 0.99) increase in BMI in boys, and 0.74% (0.28, 1.02) increase in girls. Between 1985 and 1995, mean height of 12-year-old boys and girls increased 3.9 and 3.2 cm, respectively. In 1985 unadjusted prevalences of combined overweight/obesity in boys and girls were 13.5% and 13.0%, respectively, and in 1995 were 24% and 24.5%. The latter values were reduced to 21.6% and 22.6% after adjusting for increased height. CONCLUSIONS: Previously reported increases in childhood overweight/obesity in Australia between 1985 and 1995 were likely to be moderately overestimated as a result of increased population height; suggesting that population height be taken into account in any pediatric investigation of changes in overweight/obesity prevalence over time.


Assuntos
Estatura/fisiologia , Índice de Massa Corporal , Obesidade Infantil/diagnóstico , Austrália/epidemiologia , Peso Corporal , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Obesidade Infantil/epidemiologia , Obesidade Infantil/fisiopatologia , Prevalência
6.
Glob Chang Biol ; 27(10): 2088-2101, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33511713

RESUMO

Context-dependencies in species' responses to the same climate change frustrate attempts to generalize and make predictions based on experimental and observational approaches in biodiversity science. Here, we propose predictability may be enhanced by explicitly incorporating macroecological context into analyses of species' responses to climate manipulations. We combined vascular plant species' responses to an 8-year, 12-site turf transplant climate change experiment set in southwestern Norway with climate niche data from the observed 151 species. We used the difference between a species' mean climate across their range and climate conditions at the transplant site ("climate differences") to predict colonization probability, extinction probability, and change in abundance of a species at a site. In analyses across species that ignore species-specific patterns, colonization success increased as species' distribution optima were increasingly warmer than the experimental target site. Extinction probability increased as species' distribution optima were increasingly colder than the target site. These patterns were reflected in change in abundance analyses. We found weak responses to increased precipitation in these oceanic climates. Climate differences were better predictors of species' responses to climate manipulations than range size. Interestingly, similar patterns were found when analyses focused on variation in species-specific responses across sites. These results provide an experimental underpinning to observational studies that report thermophilization of communities and suggest that space-for-time substitutions may be valid for predicting species' responses to climate warming, given other conditions are accounted for (e.g., soil nutrients). Finally, we suggest that this method of putting climate change experiments into macroecological context has the potential to generalize and predict species' responses to climate manipulations globally.


Assuntos
Biodiversidade , Mudança Climática , Noruega , Solo , Especificidade da Espécie
7.
Molecules ; 26(16)2021 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-34443665

RESUMO

The accelerated formation of 2,3-diphenylquinoxalines in microdroplets generated in a nebulizer has been investigated by competition experiments in which equimolar quantities of 1,2-phenylenediamine, C6H4(NH2)2, and a 4-substituted homologue, XC6H3(NH2)2 [X = F, Cl, Br, CH3, CH3O, CO2CH3, CF3, CN or NO2], or a 4,5-disubstituted homologue, X2C6H2(NH2)2 [X = F, Cl, Br, or CH3], compete to condense with benzil, (C6H5CO)2. Electron-donating substituents (X = CH3 and CH3O) accelerate the reaction; in contrast, electron-attracting substituents (X = F, Cl, Br and particularly CO2CH3, CN, CF3 and NO2) retard it. A structure-reactivity relationship in the form of a Hammett correlation has been found by analyzing the ratio of 2,3-diphenylquinoxaline and the corresponding substituted-2,3-diphenylquinoxaline, giving a ρ value of -0.96, thus confirming that the electron density in the aromatic ring of the phenylenediamine component is reduced in the rate-limiting step in this accelerated condensation. This correlation shows that the phenylenediamine acts as a nucleophile in the reaction.

8.
Ecol Modell ; 436: 109288, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32982015

RESUMO

In this letter we present comments on the article "A global-scale ecological niche model to predict SARS-CoV-2 coronavirus" by Coro published in 2020.

9.
Palliat Med ; 33(1): 109-113, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30404581

RESUMO

BACKGROUND:: This case report describes a patient with known idiopathic Parkinson's disease, being managed with transdermal rotigotine, whose refractory nausea and vomiting was successfully controlled with subcutaneous levomepromazine. No drug-induced extrapyramidal side effects emerged. CASE PRESENTATION:: A patient was found to have a locally advanced serous carcinoma, causing secondary bowel obstruction. Furthermore, due to compromised oral access, the patient's oral antiparkinsonian medications for motor control were converted to transdermal rotigotine. Unfortunately, the patient's nausea and vomiting was refractory to a number of recommended antiemetic options. CASE MANAGEMENT:: Low dose levomepromazine was administered on a, 'when required' basis, via subcutaneous injection. CASE OUTCOME:: After the first dose of levomepromazine, the patient's nausea and vomiting completely subsided and no extrapyramidal side effects were observed. This was confirmed by daily assessments, revealing no worsening of the motor symptoms associated with idiopathic Parkinson's disease. CONCLUSIONS:: The pharmacology of rotigotine and levomepromazine appear complementary and may allow for the simultaneous use of both drugs, with favourable outcomes. This case report highlights that rotigotine may afford protection against antipsychotic induced extrapyramidal side effects, while preserving antiemetic effects. Such combinations may have a role in the end-of-life management of idiopathic Parkinson's disease.


Assuntos
Antipsicóticos/uso terapêutico , Metotrimeprazina/uso terapêutico , Náusea/tratamento farmacológico , Náusea/etiologia , Doença de Parkinson/complicações , Tetra-Hidronaftalenos/uso terapêutico , Tiofenos/uso terapêutico , Vômito/tratamento farmacológico , Vômito/etiologia , Administração Cutânea , Idoso , Antiparkinsonianos/administração & dosagem , Antiparkinsonianos/uso terapêutico , Antipsicóticos/administração & dosagem , Agonistas de Dopamina/administração & dosagem , Agonistas de Dopamina/uso terapêutico , Feminino , Humanos , Metotrimeprazina/administração & dosagem , Tetra-Hidronaftalenos/administração & dosagem , Tiofenos/administração & dosagem , Adesivo Transdérmico , Resultado do Tratamento
10.
J Sports Sci ; 37(5): 492-499, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30105950

RESUMO

Children's fundamental movement skill levels (FMS) predict moderate-to-vigorous physical activity (MVPA). Asian children have been reported as less active than English-Europeans, possibly due to poorer skills. This study compared the FMS of children from Culturally and Linguistically Diverse (CALD) backgrounds and examined FMS correlates. A total of 261 children (122 males) aged 9-to-11 years were divided based on language spoken at home: English-European (n = 105) and Asian (n = 156). Height, mass, FMS (Test of Gross Motor Development-2), MVPA (accelerometer) and cardio-respiratory fitness (20m multistage shuttle run) were directly measured. Sex, age, language and perceived sport competence (CY-PSPP) were self-reported. Independent sample t-tests assessed age, BMI, FMS and perception by CALD group. Linear mixed models examined FMS correlates. Asian-speaking children had lower object control skill (35.5 v 37.2; CI [0.17, 3.18]; p < 0.03) compared to English-European- children, but no between-group differences in locomotor skills were observed. Fitness, physical activity and sport competence perception were positively associated with object control, yet adjusting for these variables (and age and BMI) did not remove the CALD effect (B = -2.02, SE = 0.69, p = 0.004). Cultural factors may affect object control competence in Asian-Australian children.


Assuntos
Povo Asiático , Cultura , Destreza Motora/fisiologia , População Branca , Povo Asiático/classificação , Austrália/etnologia , Estatura , Índice de Massa Corporal , Peso Corporal , Aptidão Cardiorrespiratória , Criança , Exercício Físico/fisiologia , Feminino , Humanos , Locomoção/fisiologia , Masculino , Autoimagem , População Branca/classificação
11.
Nature ; 538(7626): E1-E2, 2016 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-27786205
12.
Ecology ; 97(10): 2791-2801, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27859101

RESUMO

Plant functional traits vary consistently along climate gradients and are therefore potential predictors of plant community response to climate change. We test this space-for-time assumption by combining a spatial gradient study with whole-community turf transplantation along temperature and precipitation gradients in a network of 12 grassland sites in Southern Norway. Using data on eight traits for 169 species and annual vegetation censuses of 235 turfs over 5 yr, we quantify trait-based responses to climate change by comparing observed community dynamics in transplanted turfs to field-parameterized null model simulations. Three traits related to species architecture (maximum height, number of dormant meristems, and ramet-ramet connection persistence) varied consistently along spatial temperature gradients and also correlated to changes in species abundances in turfs transplanted to warmer climates. Two traits associated with resource acquisition strategy (SLA, leaf area) increased along spatial temperature gradients but did not correlate to changes in species abundances following warming. No traits correlated consistently with precipitation. Our study supports the hypothesis that spatial associations between plant traits and broad-scale climate variables can be predictive of community response to climate change, but it also suggests that not all traits with clear patterns along climate gradients will necessarily influence community response to an equal degree.


Assuntos
Biodiversidade , Mudança Climática , Noruega , Folhas de Planta , Plantas
13.
Calcif Tissue Int ; 99(1): 56-65, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26983726

RESUMO

Targeted weight-bearing activities during the pre-pubertal years can improve cortical bone mass, structure and distribution, but less is known about the influence of habitual physical activity (PA) and fitness. This study examined the effects of contrasting habitual PA and fitness levels on cortical bone density, geometry and mass distribution in pre-pubertal children. Boys (n = 241) and girls (n = 245) aged 7-9 years had a pQCT scan to measure tibial mid-shaft total, cortical and medullary area, cortical thickness, density, polar strength strain index (SSIpolar) and the mass/density distribution through the bone cortex (radial distribution divided into endo-, mid- and pericortical regions) and around the centre of mass (polar distribution). Four contrasting PA and fitness groups (inactive-unfit, inactive-fit, active-unfit, active-fit) were generated based on daily step counts (pedometer, 7-days) and fitness levels (20-m shuttle test and vertical jump) for boys and girls separately. Active-fit boys had 7.3-7.7 % greater cortical area and thickness compared to inactive-unfit boys (P < 0.05), which was largely due to a 6.4-7.8 % (P < 0.05) greater cortical mass in the posterior-lateral, medial and posterior-medial 66 % tibial regions. Cortical area was not significantly different across PA-fitness categories in girls, but active-fit girls had 6.1 % (P < 0.05) greater SSIpolar compared to inactive-fit girls, which was likely due to their 6.7 % (P < 0.05) greater total bone area. There was also a small region-specific cortical mass benefit in the posterior-medial 66 % tibia cortex in active-fit girls. Higher levels of habitual PA-fitness were associated with small regional-specific gains in 66 % tibial cortical bone mass in pre-pubertal children, particularly boys.


Assuntos
Densidade Óssea/fisiologia , Desenvolvimento Ósseo , Osso Cortical/fisiologia , Exercício Físico/fisiologia , Tíbia/fisiologia , Criança , Feminino , Humanos , Masculino , Aptidão Física , Suporte de Carga/fisiologia
14.
Int J Behav Nutr Phys Act ; 13: 64, 2016 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-27267965

RESUMO

BACKGROUND: The objective of this study was to investigate the effect of a 4-year specialist-taught Physical Education (PE) program on physical activity (PA) among primary school children. METHODS: A 4-year cluster randomised controlled trial was conducted in children (initially aged 8 years) from 29 primary schools (13 Intervention, 16 Control). Intervention students (N = 457) received 2 × 45 min PE lessons per week from specialist-trained PE teachers (68 lessons per year, 272 lessons over 4 years). Control group students (N = 396) received usual practice PE from generalist classroom teachers. PA during PE lessons was examined using the System for Observing Fitness Instruction Time (SOFIT). Pedometers (steps/day) were worn for 7 days each year, and accelerometers were worn concurrently in the final two years to assess moderate to vigorous (MVPA) and sedentary activity. Linear and generalized mixed models were used to determine differences in Intervention and Control student PA and the proportion of students meeting PA guidelines. RESULTS: The intervention increased SOFIT-observed student MVPA during PE lessons by 6.5 mins (16.7 v 10.2, p < 0.001). Within intervention schools, participants increased their whole-day step counts (boys = 449 [CI,140 to 756]; girls = 424 [CI,222 to 626]) and minutes of MVPA (boys = 8.0 [CI,6.8 to 9.2]; girls = 3.5 [CI,1.7 to 5.4]) on PE days. However, compared to the Control group the Intervention did not: increase habitual steps/day or MVPA when averaged over 7 days; elicit greater improvements in these measures over time; or increase the odds of meeting step/day or MVPA recommendations. At age 11 years Intervention group boys were 20 mins less sedentary per day (380 [CI,369 to 391] vs 360 [CI,350 to 369]) and this effect was sustained at age 12 years. CONCLUSIONS: Well-designed specialist-taught PE can improve student PA during PE lessons. However for PE to be a significant contributor to improving habitual PA in pre-adolescent children, daily classes are likely to be required, and even this would need to be supplemented with a wider multicomponent strategy. Our finding of a reduction in sedentary time among Intervention boys warrants further investigation into the potential role PE could play in influencing sedentary behaviour.


Assuntos
Comportamento Infantil , Exercício Físico , Educação Física e Treinamento , Instituições Acadêmicas , Comportamento Sedentário , Ensino/métodos , Actigrafia , Criança , Currículo , Feminino , Comportamentos Relacionados com a Saúde , Humanos , Masculino , Atividade Motora , Esforço Físico , Aptidão Física , Estudantes
15.
Mol Pharm ; 12(11): 4077-84, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26473653

RESUMO

Three dimensional printing (3D printing) was used to fabricate novel oral drug delivery devices with specialized design configurations. Each device was loaded with multiple actives, with the intent of applying this process to the production of personalized medicines tailored at the point of dispensing or use. A filament extruder was used to obtain drug-loaded--paracetamol (acetaminophen) or caffeine--filaments of poly(vinyl alcohol) with characteristics suitable for use in fused-deposition modeling 3D printing. A multinozzle 3D printer enabled fabrication of capsule-shaped solid devices containing the drug with different internal structures. The design configurations included a multilayer device, with each layer containing drug, whose identity was different to the drug in the adjacent layers, and a two-compartment device comprising a caplet embedded within a larger caplet (DuoCaplet), with each compartment containing a different drug. Raman spectroscopy was used to collect 2-dimensional hyper spectral arrays across the entire surface of the devices. Processing of the arrays using direct classical least-squares component matching to produce false color representations of distribution of the drugs was used. This clearly showed a definitive separation between the drug layers of paracetamol and caffeine. Drug release tests in biorelevant bicarbonate media showed unique drug release profiles dependent on the macrostructure of the devices. In the case of the multilayer devices, release of both paracetamol and caffeine was simultaneous and independent of drug solubility. With the DuoCaplet design, it was possible to engineer either rapid drug release or delayed release by selecting the site of incorporation of the drug in the device; the lag-time for release from the internal compartment was dependent on the characteristics of the external layer. The study confirms the potential of 3D printing to fabricate multiple-drug containing devices with specialized design configurations and unique drug release characteristics, which would not otherwise be possible using conventional manufacturing methods.


Assuntos
Acetaminofen/química , Cafeína/química , Composição de Medicamentos/métodos , Impressão Tridimensional/instrumentação , Comprimidos/química , Liberação Controlada de Fármacos , Humanos , Polímeros/química , Tecnologia Farmacêutica
16.
Nature ; 498(7455): E11-2, 2013 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-23803851
17.
Am J Biol Anthropol ; 184(3): e24938, 2024 07.
Artigo em Inglês | MEDLINE | ID: mdl-38623788

RESUMO

OBJECTIVES: This research aimed to replicate the Swinson, D., Snaith, J., Buckberry, J., & Brickley, M. (2010). High performance liquid chromatography (HPLC) in the investigation of gout in paleopathology. International Journal of Osteoarchaeology, 20, 135-143. https://doi.org/10.1002/oa.1009 method for detecting uric acid in archeological human remains to investigate gout in past populations and to improve the original High Performance Liquid Chromatography-ultraviolet (HPLC-UV) method by using HPLC-mass spectrometry (HPLC-MS), a more sensitive, compound-specific detection method. MATERIALS AND METHODS: We used reference samples of uric acid to create a dilution series to assess the limits of quantification and detection. Samples from individuals with and without gout lesions were taken from foot bones and ribs from the English cemeteries of Tanyard, Hickleton, Gloucester, and Lincoln. RESULTS: We could not replicate the results of Swinson and colleagues using HPLC-UV. Tests using a dilution series of uric acid showed HPLC-MS was approximately 100× more sensitive than HPLC-UV, with the additional benefit of being compound specific. A newly developed hydrophilic interaction chromatography (HILIC) method improved retention characteristics. Fourteen samples from eight individuals, five with skeletal lesions consistent with gout, were analyzed with the final method. None showed evidence of uric acid despite the newly developed method's improved sensitivity and specificity. DISCUSSION: The lack of detectable uric acid extracted from these samples suggests that (1) urate crystals were not present in any of the bone samples, regardless of gout status; (2) urate crystals did not survive these specific archeological conditions; or (3) the concentration of uric acid in our bone extracts was low, and thus larger samples would be required.


Assuntos
Gota , Ácido Úrico , Humanos , Cromatografia Líquida de Alta Pressão/métodos , Ácido Úrico/análise , Ácido Úrico/química , Gota/diagnóstico , Restos Mortais/química , Espectrometria de Massas/métodos
18.
Sports Med ; 54(3): 727-741, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38051495

RESUMO

BACKGROUND: Athletes and military personnel are often expected to compete and work in hot and/or humid environments, where decrements in performance and an increased risk of exertional heat illness are prevalent. A physiological strategy for reducing the adverse effects of heat stress is to acclimatise to the heat. OBJECTIVE: The aim of this systematic review was to quantify the effects of relocating to a hotter climate to undergo heat acclimatisation in athletes and military personnel. ELIGIBILITY CRITERIA: Studies investigating the effects of heat acclimatisation in non-acclimatised athletes and military personnel via relocation to a hot climate for < 6 weeks were included. DATA SOURCES: MEDLINE, SPORTDiscus, CINAHL Plus with Full Text and Scopus were searched from inception to June 2022. RISK OF BIAS: A modified version of the McMaster critical review form was utilised independently by two authors to assess the risk of bias. DATA SYNTHESIS: A Bayesian multi-level meta-analysis was conducted on five outcome measures, including resting core temperature and heart rate, the change in core temperature and heart rate during a heat response test and sweat rate. Wet-bulb globe temperature (WBGT), daily training duration and protocol length were used as predictor variables. Along with posterior means and 90% credible intervals (CrI), the probability of direction (Pd) was calculated. RESULTS: Eighteen articles from twelve independent studies were included. Fourteen articles (nine studies) provided data for the meta-analyses. Whilst accounting for WBGT, daily training duration and protocol length, population estimates indicated a reduction in resting core temperature and heart rate of - 0.19 °C [90% CrI: - 0.41 to 0.05, Pd = 91%] and - 6 beats·min-1 [90% CrI: - 16 to 5, Pd = 83%], respectively. Furthermore, the rise in core temperature and heart rate during a heat response test were attenuated by - 0.24 °C [90% CrI: - 0.67 to 0.20, Pd = 85%] and - 7 beats·min-1 [90% CrI: - 18 to 4, Pd = 87%]. Changes in sweat rate were conflicting (0.01 L·h-1 [90% CrI: - 0.38 to 0.40, Pd = 53%]), primarily due to two studies demonstrating a reduction in sweat rate following heat acclimatisation. CONCLUSIONS: Data from athletes and military personnel relocating to a hotter climate were consistent with a reduction in resting core temperature and heart rate, in addition to an attenuated rise in core temperature and heart rate during an exercise-based heat response test. An increase in sweat rate is also attainable, with the extent of these adaptations dependent on WBGT, daily training duration and protocol length. PROSPERO REGISTRATION: CRD42022337761.


Assuntos
Transtornos de Estresse por Calor , Militares , Humanos , Teorema de Bayes , Temperatura Alta , Exercício Físico/fisiologia , Atletas
19.
Med Sci Sports Exerc ; 56(4): 697-705, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38051094

RESUMO

PURPOSE: This study aimed to investigate the associations of biological sex and aerobic fitness (i.e., V̇O 2peak ) on the change in gastrointestinal temperature (∆ Tgi ) and whole-body sweat rate (WBSR) of children exercising in warm conditions. METHODS: Thirty-eight children (17 boys, mean ± SD = 13.7 ± 1.2 yr; 21 girls, 13.6 ± 1.8 yr) walked for 45 min at a fixed rate of metabolic heat production (8 W·kg -1 ) in 30°C and 40% relative humidity. Biological sex and relative V̇O 2peak were entered as predictors into a Bayesian hierarchical generalized additive model for Tgi . For a subsample of 13 girls with measured body composition, body fat percent was entered into a separate hierarchical generalized additive model for Tgi . Sex, V̇O 2peak , and the evaporative requirement for heat balance ( Ereq ) were entered into a Bayesian hierarchical linear regression for WBSR. RESULTS: The mean ∆ Tgi for boys was 0.71°C (90% credible interval = 0.60-0.82) and for girls 0.78°C (0.68-0.88). A predicted 20 mL·kg -1 ·min -1 higher V̇O 2peak resulted in a 0.19°C (-0.03 to 0.43) and 0.24°C (0.07-0.40) lower ∆ Tgi in boys and girls, respectively. A predicted ~13% lower body fat in the subsample of girls resulted in a 0.15°C (-0.12 to 0.45) lower ∆ Tgi . When Ereq was standardized to the grand mean, the difference in WBSR between boys and girls was -0.00 L·h -1 (-0.06 to 0.06), and a 20-mL·kg -1 ·min -1 higher predicted V̇O 2peak resulted in a mean difference in WBSR of -0.07 L·h -1 (-0.15 to 0.00). CONCLUSIONS: Biological sex did not independently influence ∆ Tgi and WBSR in children. However, a higher predicted V̇O 2peak resulted in a lower ∆ Tgi of children, which was not associated with a greater WBSR, but may be related to differences in body fat percent between high and low fitness individuals.


Assuntos
Exercício Físico , Sudorese , Masculino , Criança , Feminino , Humanos , Temperatura , Teorema de Bayes , Regulação da Temperatura Corporal , Temperatura Alta , Consumo de Oxigênio
20.
RSC Pharm ; 1(2): 272-282, 2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38899150

RESUMO

Mitonafide-loaded liposomes are a promising strategy to overcome the neurotoxicity observed in clinical trials for this drug. This study investigates the influence of loaded mitonafide or a dimer analogue on different liposomal formulations and their therapeutic efficacy in vitro. Physicochemical properties of the liposomes were manipulated using different loading methods (namely bilayer or core loading) and varying the rigidity of the bilayer using distinct phospholipid compositions. Our results demonstrated that the mitonafide dimer analogue had a comparable encapsulation efficiency (EE%) into the liposomes when loaded into rigid or flexible bilayers in contrast to the low mitonafide monomer EE%. A pH gradient core loading method resulted in a more efficient mechanism to load the monomer into the liposomes. DOSY NMR and spectrofluorometric studies revealed key differences in the structure of the vesicles and the arrangement of the monomer or the dimer in the bilayer or the core of the liposomes. The in vitro assessment of the formulations using MDA-MB-231 and RT-112 cells revealed that a flexible lipid bilayer allows a faster drug release, which correlated well with the spectroscopy studies. This study investigated for the first time that the characteristics of the lipid bilayer and the loading method influence the encapsulation efficacy, colloidal properties, photoactivity and stability of mono and bis-naphthalimides loaded in a liposomal carrier, essential factors that will impact the performance of the formulation in a biological scenario.

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