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1.
PLoS Pathog ; 19(7): e1011526, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37494402

RESUMO

Mammalian cells synthesize the antioxidant glutathione (GSH) to shield cellular biomolecules from oxidative damage. Certain bacteria, including the gastric pathogen Helicobacter pylori, can perturb host GSH homeostasis. H. pylori infection significantly decreases GSH levels in host tissues, which has been attributed to the accumulation of reactive oxygen species in infected cells. However, the precise mechanism of H. pylori-induced GSH depletion remains unknown, and tools for studying this process during infection are limited. We developed an isotope-tracing approach to quantitatively monitor host-derived GSH in H. pylori-infected cells by mass spectrometry. Using this method, we determined that H. pylori catabolizes reduced GSH from gastric cells using γ-glutamyl transpeptidase (gGT), an enzyme that hydrolyzes GSH to glutamate and cysteinylglycine (Cys-Gly). gGT is an established virulence factor with immunomodulatory properties that is required for H. pylori colonization in vivo. We found that H. pylori internalizes Cys-Gly in a gGT-dependent manner and that Cys-Gly production during H. pylori infection is coupled to the depletion of intracellular GSH from infected cells. Consistent with bacterial catabolism of host GSH, levels of oxidized GSH did not increase during H. pylori infection, and exogenous antioxidants were unable to restore the GSH content of infected cells. Altogether, our results indicate that H. pylori-induced GSH depletion proceeds via an oxidation-independent mechanism driven by the bacterial enzyme gGT, which fortifies bacterial acquisition of nutrients from the host. Additionally, our work establishes a method for tracking the metabolic fate of host-derived GSH during infection.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Animais , Helicobacter pylori/metabolismo , Infecções por Helicobacter/microbiologia , Estômago , Glutationa/metabolismo , Antioxidantes/metabolismo , Mucosa Gástrica/microbiologia , Mamíferos
2.
Childs Nerv Syst ; 40(2): 603-605, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37874377

RESUMO

PURPOSE: Cerebral sinovenous thrombosis is an increasingly recognized cause of stroke in children and neonates. Its true incidence appears to be underestimated. Despite being a rare event, certain studies have found a correlation between subdural hemorrhage and cerebral sinus thrombosis. The literature suggests that spontaneous cerebral sinovenous thrombosis in the pediatric population may lead to the occurrence of a subdural hemorrhage. In this report, we present a case of cerebral venous thrombosis associated with chronic subdural hematoma and review the literature to highlight the importance of these conditions. CASE REPORT: An 11-year-old boy was admitted in the neurosurgery department with headache and a neurological examination without changes. The imaging studies identified a heterogeneous subdural collection in the fronto-temporo-parietal region. The patient underwent surgical drainage of the subdural hematoma, and the procedure was performed without complications. The magnetic resonance and angiography showed an extensive thrombosis of the superior sagittal sinus, extending downward to the occipital sinus and partially to the right transverse sinus. CONCLUSIONS: Appropriate management in the diagnosis and an early treatment of dural sinus thrombosis associated with subdural hemorrhage can reduce the risk of recurrence and improve the clinical outcome.


Assuntos
Cavidades Cranianas , Trombose dos Seios Intracranianos , Criança , Masculino , Recém-Nascido , Humanos , Hematoma Subdural/complicações , Hematoma Subdural/diagnóstico por imagem , Hematoma Subdural/cirurgia , Trombose dos Seios Intracranianos/complicações , Trombose dos Seios Intracranianos/diagnóstico por imagem , Trombose dos Seios Intracranianos/cirurgia , Imageamento por Ressonância Magnética/efeitos adversos , Seio Sagital Superior/patologia
3.
Mol Biol Evol ; 37(11): 3258-3266, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32520985

RESUMO

The rate and spectrum of spontaneous mutations are critical parameters in basic and applied biology because they dictate the pace and character of genetic variation introduced into populations, which is a prerequisite for evolution. We use a mutation-accumulation approach to estimate mutation parameters from whole-genome sequence data from multiple genotypes from multiple populations of Daphnia magna, an ecological and evolutionary model system. We report extremely high base substitution mutation rates (µ-n,bs = 8.96 × 10-9/bp/generation [95% CI: 6.66-11.97 × 10-9/bp/generation] in the nuclear genome and µ-m,bs = 8.7 × 10-7/bp/generation [95% CI: 4.40-15.12 × 10-7/bp/generation] in the mtDNA), the highest of any eukaryote examined using this approach. Levels of intraspecific variation based on the range of estimates from the nine genotypes collected from three populations (Finland, Germany, and Israel) span 1 and 3 orders of magnitude, respectively, resulting in up to a ∼300-fold difference in rates among genomic partitions within the same lineage. In contrast, mutation spectra exhibit very consistent patterns across genotypes and populations, suggesting the mechanisms underlying the mutational process may be similar, even when the rates at which they occur differ. We discuss the implications of high levels of intraspecific variation in rates, the importance of estimating gene conversion rates using a mutation-accumulation approach, and the interacting factors influencing the evolution of mutation parameters. Our findings deepen our knowledge about mutation and provide both challenges to and support for current theories aimed at explaining the evolution of the mutation rate, as a trait, across taxa.


Assuntos
Daphnia/genética , Taxa de Mutação , Animais , Acúmulo de Mutações , Sequenciamento Completo do Genoma
4.
Mol Biol Evol ; 36(9): 1942-1954, 2019 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-31077327

RESUMO

Microsatellite loci (tandem repeats of short nucleotide motifs) are highly abundant in eukaryotic genomes and often used as genetic markers because they can exhibit variation both within and between populations. Although widely recognized for their mutability and utility, the mutation rates of microsatellites have only been empirically estimated in a few species, and have rarely been compared across genotypes and populations within a species. Here, we investigate the dynamics of microsatellite mutation over long- and short-time periods by quantifying the starting abundance and mutation rates for microsatellites for six different genotypes of Daphnia magna, an aquatic microcrustacean, collected from three populations (Finland, Germany, and Israel). Using whole-genome sequences of these six starting genotypes, descendent mutation accumulation (MA) lines, and large population controls (non-MA lines), we find each genotype exhibits a distinctive initial microsatellite profile which clusters according to the population-of-origin. During the period of MA, we observe motif-specific, highly variable, and rapid microsatellite mutation rates across genotypes of D. magna, the average of which is order of magnitude greater than the recently reported rate observed in a single genotype of the congener, Daphnia pulex. In our experiment, genotypes with more microsatellites starting out exhibit greater losses and those with fewer microsatellites starting out exhibit greater gains-a context-dependent mutation bias that has not been reported previously. We discuss how genotype-specific mutation rates and spectra, in conjunction with evolutionary forces, can shape both the differential accumulation of repeat content in the genome and the evolution of mutation rates.


Assuntos
Daphnia/genética , Variação Genética , Repetições de Microssatélites , Taxa de Mutação , Animais , Feminino , Acúmulo de Mutações
5.
Microb Ecol ; 79(3): 731-742, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31377832

RESUMO

Studies of how the microbiome varies among individuals, populations, and abiotic conditions are critical for understanding this key component of an organism's biology and ecology. In the case of Daphnia, aquatic microcrustaceans widely used in population/community ecology and environmental science studies, understanding factors that influence microbiome shifts among individuals is useful for both basic and applied research contexts. In this study, we assess differences in the microbiome among genotypes of D. magna collected from three regions along a large latitudinal gradient (Finland, Germany, and Israel). After being reared in the lab for many years, we sought to characterize any differences in genotype- or population-specific microbial communities, and to assess whether the microbiota varied among temperatures. Our study is similar to a recent comparison of the microbial communities among D. magna genotypes raised in different temperatures published by Sullam et al. (Microb Ecol 76(2):506-517, 2017), and as such represents one of the first examples of a reproducible result in microbiome research. Like the previous study, we find evidence for a strong effect of temperature on the microbiome of D. magna, although across a much smaller temperature range representing potential near-future climates. In addition, we find evidence that the microbiomes of D. magna genotypes from different regions are distinct, even years after being brought into the laboratory. Finally, our results highlight a potentially common finding in the expanding area of microbiome research-differences among treatments are not necessarily observed in the most abundant taxonomic groups. This highlights the importance of considering sampling scheme and depth of coverage when characterizing the microbiome, as different experimental designs can significantly impact taxon-specific results, even when large-scale effects are reproduced.


Assuntos
Fenômenos Fisiológicos Bacterianos , Daphnia/microbiologia , Genótipo , Interações entre Hospedeiro e Microrganismos , Microbiota , Animais , Bactérias/classificação , Daphnia/genética , Finlândia , Geografia , Alemanha , Israel , Temperatura
6.
J Chem Phys ; 151(11): 114907, 2019 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-31542012

RESUMO

Janus particles interfacially self-assemble into different structures when incorporated into multiphase systems. Dissipative particle dynamics simulations are employed herein to investigate the interplay between aggregation mechanisms and phase separation in polymer blends. Shorter rods with a standing configuration become increasingly "caged" or trapped in larger aggregates as weight fraction increases, which is reflected in the way that their diffusion is coupled to their aggregation rates. Janus rods of higher aspect ratios that are tilted at the interface aggregate side-by-side and are able to hinder phase separation kinetics. This is due to a combination of individual Janus rod conformations at the interface, their intrinsic aggregation mechanisms, aggregate fractal dimension, and aggregation rates, and can also be traced back to the scaling of the diffusion coefficient of aggregates with their size. Findings presented provide insight into the mechanisms governing two dimensionally growing colloidal aggregates at fluid interfaces, more specifically, those associated with Janus particles, and shed light on the potential of these systems in paving the way for designing new functional materials.

7.
Arch Toxicol ; 93(3): 649-658, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30659320

RESUMO

Cannabis use has become a hot topic in several countries due to the debate about its legalization for medical purposes. However, data are limited regarding adverse events, safety and potential impact on reproductive health. Cannabis consumption during pregnancy has been associated with gestational disorders such as preterm birth, intrauterine growth restriction, low birth weight and increased risk of miscarriage, though the underlying biochemical mechanisms are still unknown. Given that the endocannabinoid system (ECS) is involved in several reproductive processes, we tested the hypothesis that the negative outcomes may result from the impact on the ECS homeostasis caused by the main psychoactive compound of cannabis, Δ9-tetrahydrocannabinol (THC). We demonstrate that THC (10-40 µM) impairs placental endocannabinoid system by disrupting the endocannabinoid anandamide (AEA) levels and the expression of AEA synthetic and degrading enzymes N-arachidonoylphosphatidylethanolamine-specific phospholipase D (NAPE-PLD) and fatty acid amide hydrolase (FAAH), respectively. Although, no alterations in cannabinoid receptors CB1 and CB2 expression were observed. Thus, long-term local AEA levels are associated with a shift in the enzymatic profile to re-establish ECS homeostasis. In chronic cannabis users, high AEA levels in placenta may disturb the delicate balance of trophoblast cells turnover leading to alterations in normal placental development and foetal growth.


Assuntos
Dronabinol/toxicidade , Endocanabinoides/metabolismo , Homeostase/efeitos dos fármacos , Placenta/efeitos dos fármacos , Psicotrópicos/toxicidade , Amidoidrolases/metabolismo , Ácidos Araquidônicos/metabolismo , Cannabis , Feminino , Humanos , Placenta/fisiologia , Alcamidas Poli-Insaturadas/metabolismo , Gravidez , Receptor CB1 de Canabinoide/metabolismo
8.
Twin Res Hum Genet ; 22(6): 800-808, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31364586

RESUMO

The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural-geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.


Assuntos
Envelhecimento/genética , Estatura/genética , Índice de Massa Corporal , Bases de Dados Factuais , Interação Gene-Ambiente , Gêmeos Dizigóticos/genética , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Fatores Socioeconômicos
9.
Int J Obes (Lond) ; 42(1): 108-110, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28811652

RESUMO

The purpose of this study was to describe sources of variability in obesity-related variables in 6022 children aged 9-11 years from 12 countries. The study design involved recruitment of students, nested within schools, which were nested within study sites. Height, weight and waist circumference (WC) were measured and body mass index (BMI) was calculated; sleep duration and total and in-school moderate-to-vigorous physical activity (MVPA) and sedentary time were measured by accelerometry; and diet scores were obtained by questionnaire. Variance in most variables was largely explained at the student level: BMI (91.9%), WC (93.5%), sleep (75.3%), MVPA (72.5%), sedentary time (76.9%), healthy diet score (88.3%), unhealthy diet score (66.2%), with the exception of in-school MVPA (53.8%) and in-school sedentary time (25.1%). Variance explained at the school level ranged from 3.3% for BMI to 29.8% for in-school MVPA, and variance explained at the site level ranged from 3.2% for WC to 54.2% for in-school sedentary time. In general, more variance was explained at the school and site levels for behaviors than for anthropometric traits. Given the variance in obesity-related behaviors in primary school children explained at school and site levels, interventions that target policy and environmental changes may enhance obesity intervention efforts.


Assuntos
Tamanho Corporal/fisiologia , Exercício Físico/fisiologia , Obesidade Infantil/epidemiologia , Índice de Massa Corporal , Criança , Comportamento Infantil , Estudos Transversais , Humanos , Obesidade Infantil/fisiopatologia , Comportamento Sedentário
10.
Osteoporos Int ; 29(10): 2261-2274, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29978256

RESUMO

The association of genetic polymorphisms with low bone mineral density in elite athletes have not been considered previously. The present study found that bone mass phenotypes in elite and pre-elite dancers are related to genetic variants at the Wnt/ß-catenin and ER pathways. INTRODUCTION: Some athletes (e.g. gymnasts, dancers, swimmers) are at increased risk for low bone mineral density (BMD) which, if untreated, can lead to osteoporosis. To investigate the association of genetic polymorphisms in the oestrogen receptor (ER) and the Wnt/ß-catenin signalling pathways with low BMD in elite and pre-elite dancers (impact sport athletes). METHODS: The study included three phases: (1) 151 elite and pre-elite dancers were screened for the presence of low BMD and traditional osteoporosis risk factors (low body weight, menstrual disturbances, low energy availability); (2) a genetic association study was conducted in 151 elite and pre-elite dancers and age- and sex- controls; (3) serum sclerostin was measured in 101 pre-elite dancers and age- and sex-matched controls within a 3-year period. RESULTS: Eighty dancers revealed low BMD: 56.3% had at least one traditional osteoporosis risk factor, whereas 28.6% did not display any risk factor (37.2% revealed traditional osteoporosis risk factors, but had normal BMD). Body weight, menstrual disturbances and energy availability did not fully predict bone mass acquisition. Instead, genetic polymorphisms in the ER and Wnt/ß-catenin pathways were found to be risk factors for low BMD in elite dancers. Sclerostin was significantly increased in dancers compared to controls during the 3-year follow-up (p < 0.05). CONCLUSIONS: Elite and pre-elite dancers demonstrate high prevalence of low BMD, which is likely related to genetic variants at the Wnt/ß-catenin and ER pathways and not to factors usually associated with BMD in athletes (body weight, menstrual disturbances, energy deficiency).


Assuntos
Densidade Óssea/genética , Dança/fisiologia , Osteoporose/genética , Polimorfismo de Nucleotídeo Único , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Antropometria/métodos , Densidade Óssea/fisiologia , Proteínas Morfogenéticas Ósseas/sangue , Estudos Transversais , Feminino , Marcadores Genéticos , Predisposição Genética para Doença , Variação Genética , Humanos , Estudos Longitudinais , Masculino , Doenças Profissionais/genética , Doenças Profissionais/fisiopatologia , Osteoporose/fisiopatologia , Receptores de Estrogênio/genética , Fatores de Risco , Transdução de Sinais/genética , Suporte de Carga/fisiologia , Via de Sinalização Wnt/genética , Adulto Jovem , beta Catenina/genética
11.
Am J Hum Biol ; 30(1)2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-28925585

RESUMO

OBJECTIVES: To investigate the relationships of biological, behavioral, familial, and environmental characteristics with siblings´ physical activity (PA) levels as well as the intrapair resemblance in PA. METHODS: The sample comprises 834 (390 females) biological siblings [brother-brother (BB), sister-sister (SS), brother-sister (BS)] aged 9 to 20 years. Total PA index (TPAI) was estimated by questionnaire. Information on potential behavioral, familial, and environmental correlates was obtained by self-report; body mass index (BMI), biological maturation, and physical fitness were measured. Multilevel models were used to analyze siblings´ clustered data, and sibling resemblance was estimated with the intraclass correlation (ρ). RESULTS: On average, younger sibs, those more physically fit, and those with more parental support had greater TPAI. Further, BB pairs had higher TPAI levels than SS or BS pairs, but also had greater within-pair variance. When adjusted for all covariates, SS pairs demonstrated greater resemblance in TPAI (ρ = 0.53, 95%CI = 0.38-0.68) than BS (ρ = 0.26, 95%CI = 0.14-0.43) or BB pairs (ρ = 0.18, 95%CI = 0.06-0.44). CONCLUSIONS: Age, physical fitness, and parental support were the best predictors of TPAI levels. A moderate level of resemblance in TPAI was observed in SS pairs, while lower resemblance was found for BS and BB pairs. These findings may be due to differences in the roles of shared genetic factors, familial, and environmental characteristics across different sibling types.


Assuntos
Exercício Físico , Crescimento , Nível de Saúde , Estilo de Vida , Aptidão Física , Irmãos , Adolescente , Criança , Feminino , Humanos , Masculino , Portugal , Adulto Jovem
12.
Scand J Med Sci Sports ; 28(11): 2358-2368, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29858513

RESUMO

Relationships among skeletal age (SA), body size and fundamental motor skills (FMS) and motor performance were considered in 155 boys and 159 girls 3-6 years of age. Stature and body mass were measured. SA of the hand-wrist was assessed with the Tanner-Whitehouse II 20 bone method. The Test of Gross Motor Development, 2nd edition (TGMD-2), and the Preschool Test Battery were used, respectively, to assess FMS and motor performance. Based on hierarchical regression analyses, the standardized residuals of SA on chronological age (SAsr) explained a maximum of 6.1% of the variance in FMS and motor performance in boys (ΔR2 3 , range 0.0%-6.1%) and a maximum of 20.4% of the variance in girls (ΔR2 3 , range 0.0%-20.4%) over that explained by body size and interactions of SAsr with body size (step 3). The interactions of the SAsr and stature and body mass (step 2) explained a maximum of 28.3% of the variance in boys (ΔR2 2 , range 0.5%-28.3%) and 16.7% of the variance in girls (ΔR2 2 , range 0.7%-16.7%) over that explained by body size alone. With the exception of balance, relationships among SAsr and FMS or motor performance differed between boys and girls. Overall, SA per se or interacting with body size had a relatively small influence in FMS and motor performance in children 3-6 years of age.


Assuntos
Desenvolvimento Infantil , Destreza Motora , Estatura , Tamanho Corporal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Equilíbrio Postural , Análise de Regressão , Esqueleto
13.
Scand J Med Sci Sports ; 28(5): 1594-1603, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29363177

RESUMO

Children change their body size, shape, and gross motor coordination (GMC) as they grow. Further, GMC is expected to link to changes in children's body size, physical activity (PA), and physical fitness (PF). The objective was to model GMC changes in children followed longitudinally and to investigate associations between these changes and PA and PF levels. A total of 245 children (122 girls) were observed at 6 years of age and followed annually until 9 years. A sequence of allometric models was fitted, that is, 1. body mass, stature, and PA; 2. addition of four PF tests; 3. addition of four more PF tests. In Model 1, changes in GMC are nonlinear, and body mass (-0.60 ± 0.07, P < .001) and stature (2.91 ± 0.35, P < .001) parameter estimates were significant suggesting children with a more linear body size/shape showed higher GMC performances. Girls tend to outperform boys across time, and PA was not associated with GMC changes. Model 2 fitted the data better, and the PF tests (handgrip, standing long jump, 50-yard dash, and shuttle run) were significantly linked to GMC change. In Model 3, adding the remaining PF tests did not change the order of any factors importance. The greatest GMC changes were achieved by children whose body size/shape has an ectomorphic dominance across the years. Considering that leaner and physically fitter children tended to be more coordinated, physical education should also focus on PF development in components related to muscular strength, speed, agility, and aerobic capacity, along with nutritional education to reduce fat mass.


Assuntos
Desenvolvimento Infantil , Exercício Físico , Destreza Motora , Aptidão Física , Estatura , Tamanho Corporal , Criança , Feminino , Força da Mão , Humanos , Estudos Longitudinais , Masculino , Modelos Teóricos , Somatotipos
14.
Child Care Health Dev ; 44(3): 443-451, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29417602

RESUMO

BACKGROUND: Given the concern for health-related consequences of an elevated body mass index (BMI; obesity), the potential consequences of a low BMI in children are often overlooked. The purpose was to evaluate the relationship between the BMI across its entire spectrum and motor coordination (MC) in children 6-10 years. METHODS: Height, weight, and MC (Körperkoordinationstest für Kinder, KTK test battery) were measured in 1,912 boys and 1,826 girls of 6-10 years of age. BMI (kg/m2 ) was calculated. KTK scores for each of the four tests were also converted to a motor quotient (MQ). One-way ANOVA was used to test differences in the BMI, individual test items, and MQ among boys and girls within age groups. Sex-specific quadratic regressions of individual KTK items and the MQ on the BMI were calculated. Girls and boys were also classified into four weight status groups using International Obesity Task Force criteria: thin, normal, overweight, and obese. Differences in specific test items and MQ between weight status groups were evaluated by age group in each sex. RESULTS: Thirty-one percent of the sample was overweight or obese, whereas 5% was thin. On average, normal weight children had the highest MQ in both sexes across the age range with few exceptions. Overweight/obese children had a lower MQ than normal weight and thin children. The quadratic regression lines generally presented an inverted parabolic relationship between the BMI and MC and suggested a decrease in MC with an increase in the BMI. CONCLUSION: In general, BMI shows a curvilinear, inverted parabolic relationship with MC in children 6-10 years.


Assuntos
Índice de Massa Corporal , Peso Corporal Ideal , Destreza Motora/fisiologia , Sobrepeso , Desempenho Psicomotor/fisiologia , Magreza , Análise de Variância , Criança , Teste de Esforço , Feminino , Inquéritos Epidemiológicos , Humanos , Masculino , Atividade Motora , Portugal/epidemiologia
15.
Osteoporos Int ; 28(10): 2903-2912, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28656365

RESUMO

According to existing literature, bone health in ballet dancers is controversial. We have verified that, compared to controls, young female and male vocational ballet dancers have lower bone mineral density (BMD) at both impact and non-impact sites, whereas female professional ballet dancers have lower BMD only at non-impact sites. INTRODUCTION: The aims of this study were to (a) assess bone mineral density (BMD) in vocational (VBD) and professional (PBD) ballet dancers and (b) investigate its association with body mass (BM), fat mass (FM), lean mass (LM), maturation and menarche. METHODS: The total of 152 VBD (13 ± 2.3 years; 112 girls, 40 boys) and 96 controls (14 ± 2.1 years; 56 girls, 40 boys) and 184 PBD (28 ± 8.5 years; 129 females, 55 males) and 160 controls (27 ± 9.5 years; 110 female, 50 males) were assessed at the lumbar spine (LS), femoral neck (FN), forearm and total body by dual-energy X-ray absorptiometry. Maturation and menarche were assessed via questionnaires. RESULTS: VBD revealed lower unadjusted BMD at all anatomical sites compared to controls (p < 0.001); following adjustments for Tanner stage and gynaecological age, female VBD showed similar BMD values at impact sites. However, no factors were found to explain the lower adjusted BMD values in VBD (female and male) at the forearm (non-impact site), nor for the lower adjusted BMD values in male VBD at the FN. Compared to controls, female PBD showed higher unadjusted and adjusted BMD for potential associated factors at the FN (impact site) (p < 0.001) and lower adjusted at the forearm (p < 0.001). Male PBD did not reveal lower BMD than controls at any site. CONCLUSIONS: Both females and males VBD have lower BMD at impact and non-impact sites compared to control, whereas this is only the case at non-impact site in female PBD. Maturation seems to explain the lower BMD at impact sites in female VBD.


Assuntos
Densidade Óssea/fisiologia , Dança/fisiologia , Saúde Ocupacional , Absorciometria de Fóton/métodos , Adolescente , Adulto , Antropometria/métodos , Índice de Massa Corporal , Estudos de Casos e Controles , Criança , Feminino , Colo do Fêmur/fisiologia , Antebraço/fisiologia , Humanos , Vértebras Lombares/fisiologia , Masculino , Menarca/fisiologia , Caracteres Sexuais , Suporte de Carga/fisiologia , Adulto Jovem
16.
Scand J Med Sci Sports ; 27(8): 842-851, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26990113

RESUMO

This study aimed to investigate the association between individual and school characteristics associated with the number of school days children comply with moderate-to-vigorous physical activity (MVPA) recommendations. Sample comprises 612 Portuguese children, aged 9-11 years, from 23 schools. Time spent in MVPA was measured by accelerometry, while individual-level correlates were obtained by anthropometry and questionnaires. School-level variables were collected by questionnaire, and accelerometer wear time and season were also considered. Maximum likelihood estimates of model parameters were obtained via a multilevel analysis with children as level-1, and school as level-2. Children who spent more time in sedentary activities and girls were less likely to comply with MVPA/daily. More mature children and those who use active transportation to school were more likely to attain the PA recommendation. Furthermore, greater accelerometer wear time and spring season increased the chance to achieve the recommended MVPA. In terms of school-level correlates, a greater number of available facilities was negatively associated with children MVPA compliance. Given the set of variables, our results showed that individual characteristics seem to be more relevant for children's compliance rates with PA/day than school context variables, which should be taken into account in the implementation of school policies and practices.


Assuntos
Exercício Físico , Cooperação do Paciente , Acelerometria , Antropometria , Criança , Feminino , Humanos , Funções Verossimilhança , Masculino , Análise Multinível , Portugal , Instituições Acadêmicas , Estações do Ano , Comportamento Sedentário , Sono , Esportes , Meios de Transporte
17.
Public Health ; 153: 16-24, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28818582

RESUMO

OBJECTIVES: To examine whether meeting vs not meeting movement/non-movement guidelines (moderate-to-vigorous physical activity [MVPA], screen time, sleep duration), and combinations of these recommendations, are associated with health-related quality of life (HRQoL) in children from 12 countries in five major geographic regions of the world and explore whether the associations vary by study site. STUDY DESIGN: Observational, multinational cross-sectional study. METHODS: This study included 6106 children aged 9-11 years from sites in Australia, Brazil, Canada, China, Colombia, Finland, India, Kenya, Portugal, South Africa, the United Kingdom, and the United States. Participants completed the KIDSCREEN-10 to provide a global measure of their HRQoL. Sleep duration and MVPA were assessed using 24-h accelerometry. Screen time was assessed through self-report. Meeting the recommendations was defined as ≥60 min/day for MVPA, ≤2 h/day for screen time, and between 9 and 11 h/night for sleep duration. Age, sex, highest parental education, unhealthy diet pattern score, and body mass index z-score were included as covariates in statistical models. RESULTS: In the full sample, children meeting the screen time recommendation, the screen time + sleep recommendation, and all three recommendations had significantly better HRQoL than children not meeting any of these guidelines. Differences in HRQoL scores between sites were also found within combinations of movement/non-movement behaviors. For example, while children in Australia, Canada, and USA self-reported better HRQoL when meeting all three recommendations, children in Kenya and Portugal reported significantly lower HRQoL when meeting all three recommendations (relative to not meeting any). CONCLUSIONS: Self-reported HRQoL is generally higher when children meet established movement/non-movement recommendations. However, differences between study sites also suggest that interventions aimed at improving lifestyle behaviors and HRQoL should be locally and culturally adapted.


Assuntos
Exercício Físico , Fidelidade a Diretrizes/estatística & dados numéricos , Guias como Assunto , Nível de Saúde , Qualidade de Vida , Austrália , Brasil , Canadá , Criança , China , Colômbia , Estudos Transversais , Europa (Continente) , Feminino , Humanos , Índia , Quênia , Masculino , Autorrelato , Estados Unidos
18.
J Helminthol ; 91(1): 87-90, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26830465

RESUMO

The prevalence of canine Dirofilaria infection in Maio Island (Cape Verde) was analysed by serology, morphological and molecular identification of the parasite species. Blood and sera were collected from 150 dogs and 80 cats aged over 6 months from various localities of the island. DNA was extracted from blood and samples were screened by polymerase chain reaction (PCR) using microfilaria-specific primers. No Dirofilaria immitis was found in dogs while D. repens microfilariae were found in 5.3% of dogs and 6% were positive by PCR. The species identity was confirmed by sequencing of PCR products, which showed almost 100% homology with D. repens European sequences published in GenBank. No difference in Dirofilaria infection was observed between males and females or in dogs with different weights. However, older dogs and those from the western part of Maio Island were more frequently infected. No Dirofilaria was found in cats. This study represents the first evidence of D. repens in Cape Verde (West Africa) and highlights the need for implementing control measures and for a better surveillance of dirofilariosis in Africa.


Assuntos
Dirofilaria repens/isolamento & purificação , Dirofilariose/epidemiologia , Dirofilariose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/parasitologia , Animais , Sangue/parasitologia , Cabo Verde/epidemiologia , Doenças do Gato/epidemiologia , Doenças do Gato/parasitologia , Gatos , DNA de Helmintos/genética , DNA de Helmintos/isolamento & purificação , Dirofilaria repens/genética , Cães , Ilhas/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Análise de Sequência de DNA
19.
Nucleic Acids Res ; 42(Web Server issue): W167-74, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24861621

RESUMO

Biological network analysis is a powerful approach to gain systems-level understanding of patterns of gene expression in different cell types, disease states and other biological/experimental conditions. Three consecutive steps are required--identification of genes or proteins of interest, network construction and network analysis and visualization. To date, researchers have to learn to use a combination of several tools to accomplish this task. In addition, interactive visualization of large networks has been primarily restricted to locally installed programs. To address these challenges, we have developed NetworkAnalyst, taking advantage of state-of-the-art web technologies, to enable high performance network analysis with rich user experience. NetworkAnalyst integrates all three steps and presents the results via a powerful online network visualization framework. Users can upload gene or protein lists, single or multiple gene expression datasets to perform comprehensive gene annotation and differential expression analysis. Significant genes are mapped to our manually curated protein-protein interaction database to construct relevant networks. The results are presented through standard web browsers for network analysis and interactive exploration. NetworkAnalyst supports common functions for network topology and module analyses. Users can easily search, zoom and highlight nodes or modules, as well as perform functional enrichment analysis on these selections. The networks can be customized with different layouts, colors or node sizes, and exported as PNG, PDF or GraphML files. Comprehensive FAQs, tutorials and context-based tips and instructions are provided. NetworkAnalyst currently supports protein-protein interaction network analysis for human and mouse and is freely available at http://www.networkanalyst.ca.


Assuntos
Mapeamento de Interação de Proteínas/métodos , Software , Animais , Gráficos por Computador , Expressão Gênica , Humanos , Internet , Camundongos , Mapas de Interação de Proteínas , Proteínas/genética
20.
Int J Obes (Lond) ; 39(10): 1467-74, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26058391

RESUMO

OBJECTIVES: The objectives of this study are to examine differences in cardiometabolic risk indicators, as well as their prevalences, in Portuguese and Mozambican youth, and to investigate the associations between weight status and cardiorespiratory fitness levels with cardiometabolic risk. METHODS: The sample comprises 721 adolescents (323 Mozambican and 398 Portuguese), aged 10-15 years. Anthropometry (height, sitting height, weight and waist circumference), blood pressure, serum-fasting triglycerides, high-density lipoprotein cholesterol and glucose, and cardiorespiratory fitness were measured. Maturity offset was estimated and a cardiometabolic risk score adjusted for sex, age and biological maturity was computed. Adolescents were classified as normal weight and overweight/obese as well as fit or unfit (cardiorespiratory fitness). RESULTS: Portuguese youth have better cardiometabolic and cardiorespiratory fitness profiles. About 32% and 30% of Portuguese boys and girls, respectively, are overweight/obese; in Mozambicans, these prevalences are 7.5% for boys and 21% for girls; in addition, 81.6% of Portuguese boys and 77.7% of Portuguese girls were classified as cardiorespiratory fit, against 54% and 44.4% of Mozambican boys and girls, respectively. No statistically significant differences (P>0.05) were found between Mozambicans and Portuguese for the cluster of three or more cardiometabolic risk indicators. A positive relationship (P<0.001) was found between weight status and cardiometabolic risk in adolescents from both countries; however, a negative association (P<0.001) between cardiorespiratory fitness and cardiometabolic risk was only found among Portuguese youth. CONCLUSIONS: Portuguese and Mozambican youth differ in their cardiometabolic risk profiles, body weight and cardiorespiratory fitness, favoring Portuguese. Overweight/obesity and low cardiorespiratory fitness levels are related to a worse cardiometabolic risk profile, being relevant to design public health intervention strategies to reduce excess weight and increase cardiorespiratory fitness.


Assuntos
Doenças Cardiovasculares/epidemiologia , Política de Saúde , Promoção da Saúde/organização & administração , Doenças Metabólicas/epidemiologia , Sobrepeso/epidemiologia , Aptidão Física , Adiposidade , Adolescente , Pressão Sanguínea , Índice de Massa Corporal , Proteína C-Reativa , Doenças Cardiovasculares/etiologia , Doenças Cardiovasculares/prevenção & controle , Criança , HDL-Colesterol , Comparação Transcultural , Feminino , Promoção da Saúde/estatística & dados numéricos , Humanos , Lipoproteínas HDL , Masculino , Doenças Metabólicas/etiologia , Doenças Metabólicas/prevenção & controle , Moçambique/epidemiologia , Sobrepeso/complicações , Sobrepeso/prevenção & controle , Portugal/epidemiologia , Prevalência , Medição de Risco , Fatores de Risco , Circunferência da Cintura , Aumento de Peso
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