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1.
J Intellect Disabil Res ; 66(6): 517-532, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35137997

RESUMO

BACKGROUND: Young adults with intellectual disability (ID) are experiencing early mortality, and it is suggested that they are living with undiagnosed cardiovascular and metabolic risk factors (hereafter referred to as cardiometabolic). METHODS: We investigated the association between modifiable risk factors and cardiometabolic health profile in adults with ID aged 18-45 years through clinical evaluation of traditional cardiometabolic parameters, and assessment of physical activity levels, diet and associated health knowledge. RESULTS: We found that young adults with ID have an increased obesity (mean body mass index; ID group: 32.9 ± 8.6 vs. control group: 26.2 ± 5.5, P = 0.001), are engaging in less physical activity than the age-matched general population (total activity minutes per week; ID group: 172.2 ± 148.9 vs. control group: 416.4 ± 277.1, P < 0.001), and overall have unhealthier diets. Additionally, knowledge about nutrition and physical activity appears to be an important predictor of cardiometabolic risk in this population. If young people with ID are to improve their cardiometabolic health to reduce morbidity and early mortality, we need to further explore how to consistently apply health messaging to get lasting behavioural change in this population.


Assuntos
Doenças Cardiovasculares , Deficiência Intelectual , Adolescente , Doenças Cardiovasculares/epidemiologia , Doenças Cardiovasculares/etiologia , Dieta , Exercício Físico , Humanos , Deficiência Intelectual/complicações , Fatores de Risco , Adulto Jovem
2.
World J Urol ; 39(7): 2621-2626, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32997261

RESUMO

PURPOSE: After Endoscopic Enucleation of the Prostate (EEP) for benign prostatic obstruction (BPO), men remain at risk for prostate cancer (PCa). Significant PSA changes occur after enucleation, which interfere with later screening for PCa. It remains unclear which patients need further diagnostic investigations for PCa after EEP. The goal of this study was to identify an independent predictor for PCa diagnosis after Holmium Laser Enucleation of the Prostate (HoLEP) in patients whose HoLEP resection specimen did not show PCa. METHODS: Data of 773 patients who underwent HoLEP for BPO between 2010 and 2018 in a referral center were analyzed. Exclusion criteria were PCa detection in the HoLEP specimen or absence of post-operative PSA values. Patients were divided in a PCa group and Control group depending on whether or not PCa was detected during follow-up after HoLEP. The predictive value for future diagnosis of PCa of different forms of PSA-change after HoLEP was analyzed by multivariate Cox regression and ROC analysis. RESULTS: Overall, 24 (4.2%) patients developed PCa after HoLEP. At 5 year follow-up, the PCa-free survival rate was 85%. First post-operative PSA was an independent predictor of PCa diagnosis after HoLEP (HR 1.106, 95% CI 1.074-1.139, p < 0.001, ROC AUC 0.903) with an optimal cut-off value of 1.73 ng/ml (sensitivity 83.3%, specificity 82.3%). CONCLUSIONS: For patients who underwent HoLEP for BPO, post-operative PSA after HoLEP is an independent predictor for future PCa diagnosis. When PSA is > 1.73 ng/ml within the first year after HoLEP, rigorous follow-up and diagnostic investigations for PCa are indicated.


Assuntos
Endoscopia , Lasers de Estado Sólido/uso terapêutico , Antígeno Prostático Específico/sangue , Prostatectomia/métodos , Hiperplasia Prostática/sangue , Hiperplasia Prostática/cirurgia , Neoplasias da Próstata/sangue , Neoplasias da Próstata/diagnóstico , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Estudos Retrospectivos
3.
Pediatr Nephrol ; 36(4): 777-788, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-32253519

RESUMO

Individuals of African origin have an increased risk of developing various progressive chronic kidney diseases (CKD). This risk has been attributed to genetic variants (G1, G2) in apolipoprotein-L1 (APOL1) gene. In the pediatric population, especially in children affected by sickle cell disease (SCD), by human immunodeficiency virus (HIV), or with various glomerular diseases, APOL1 risk variants have been associated with the development of hypertension, albuminuria, and more rapid decline of kidney function. The present review focuses on existing APOL1-related epidemiological data in children with CKD. It also includes data from studies addressing racial disparities in CKD, the APOL1-related innate immunity, and the relationship between APOL1 and CKD and pathogenic pathways mediating APOL1-related kidney injury.


Assuntos
Apolipoproteína L1 , Insuficiência Renal Crônica , Albuminúria , Apolipoproteína L1/genética , Criança , Predisposição Genética para Doença , Humanos , Rim , Insuficiência Renal Crônica/epidemiologia , Insuficiência Renal Crônica/genética
4.
Int J Behav Nutr Phys Act ; 17(1): 142, 2020 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-33239036

RESUMO

BACKGROUND: Physical inactivity is a global pandemic associated with a high burden of disease and premature mortality. There is also a trend in growing economic inequalities which impacts population health. There is no global analysis of the relationship between income inequality and population levels of physical inactivity. METHODS: Two thousand sixteen World Health Organisation's country level data about compliance with the 2010 global physical activity guidelines were analysed against country level income interquantile ratio data obtained from the World Bank, OECD and World Income Inequality Database. The analysis was stratified by country income (Low, Middle and High) according to the World Bank classification and gender. Multiple regression was used to quantify the association between physical activity and income inequality. Models were adjusted for GDP and percentage of GDP spent on health care for each country and out of pocket health care spent. RESULTS: Significantly higher levels of inactivity and a wider gap between the percentage of women and men meeting global physical activity guidelines were found in countries with higher income inequality in high and middle income countries irrespective of a country wealth and spend on health care. For example, in higher income countries, for each point increase in the interquantile ratio data, levels of inactivity in women were 3.73% (CI 0.89 6.57) higher, levels of inactivity in men were 2.04% (CI 0.08 4.15) higher and the gap in inactivity levels between women and men was 1.50% larger (CI 0.16 2.83). Similar relationships were found in middle income countries with lower effect sizes. These relationships were, however, not demonstrated in the low-income countries. CONCLUSIONS: Economic inequalities, particularly in high- and middle- income countries might contribute to physical inactivity and might be an important factor to consider and address in order to combat the global inactivity pandemic and to achieve the World Health Organisation target for inactivity reduction.


Assuntos
Fatores Econômicos , Exercício Físico , Renda , Comportamento Sedentário , Adulto , Países Desenvolvidos , Países em Desenvolvimento , Feminino , Nível de Saúde , Humanos , Masculino , Fatores Sexuais , Organização Mundial da Saúde
5.
Int J Obes (Lond) ; 43(3): 603-614, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30283079

RESUMO

OBJECTIVES: This study examines the prospective association between sugar-sweetened beverages (SSB) consumption and change in body weight over a 4-5-year period in a socio-economically disadvantaged South African population. METHODS: This is a longitudinal study involving 800 adults (212 men, 588 women); 247 from the original METS (Modelling the Epidemiological Transition Study) cohort (N = 504) and 553 of the original 949 members of the PURE (Prospective Urban and Rural Epidemiology) Study. Both cohorts were drawn from low-income, socio-economically disadvantaged communities. Mean follow-up duration and age were 4.5 (SD 0.45) and 50.0 (SD 11.8) years, respectively. Harmonised measurements included body mass index, self-reported moderate-to-vigorous physical activity, and intake of meat, snacks and 'take-aways', fruits and vegetables and SSB (in servings/week). Multivariate logistic regression models were developed to determine the extent to which SSB consumption predicted relative weight gain, after controlling for potential confounders and known predictors. RESULTS: Nearly a third (29%) of participants had a relative weight change ≥5.0%; higher in the non-obese compared to the obese group (32% vs. 25%; p = 0.026). The average SSB consumption was 9.9 servings/week and was higher in the food insecure compared to the food secure group (11.5 vs. 9.0 servings/week; p = 0.006); but there were no differences between women and men (10.3 vs. 9.1 servings/week; p = 0.054). Mean SSB consumption was higher in the group who gained ≥5% weight compared to those who did not (11.0 vs. 8.7; p = 0.004). After adjustment, SSB consumption of 10 or more servings/week was associated with a 50% greater odds of gaining at least 5% body weight (AOR: 1.50, 95% CI (1.05-2.18)). CONCLUSION: These results show that higher intake of SSB predicts weight gain in a sample of South Africans drawn from low-income settings. Comprehensive, population-wide interventions are needed to reduce SSB consumption in these settings.


Assuntos
Dieta/estatística & dados numéricos , Bebidas Adoçadas com Açúcar/estatística & dados numéricos , Aumento de Peso/fisiologia , Adulto , Feminino , Abastecimento de Alimentos/estatística & dados numéricos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Pobreza , África do Sul/epidemiologia
6.
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
7.
Mol Psychiatry ; 22(1): 134-141, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27046647

RESUMO

Norepinephrine released from sympathetic nerves is removed from the neuroeffector junction via the action of the norepinephrine transporter (NET). NET impairment is evident in several clinically important conditions including major depressive disorder (MDD), panic disorder (PD), essential hypertension and the postural orthostatic tachycardia syndrome (POTS). We aimed to determine whether a single nucleotide polymorphism (SNP) in the 3' untranslated region (UTR) of the NET gene is associated with NET impairment and to elucidate the mechanisms involved. The analyses were carried out in two cohorts of European ancestry, which included healthy controls and MDD, PD, hypertensive and POTS patients. Compared with controls, cases had significantly higher prevalence of the T allele of rs7194256 (C/T), arterial norepinephrine, depression and anxiety scores, larger left ventricular mass index, higher systolic and diastolic blood pressures, and heart rate. Bioinformatic analysis identified that the microRNA miR-19a-3p could bind preferentially to the sequence created by the presence of the T allele. This was supported by results of luciferase assays. Compared with controls, cases had significantly lower circulating miR-19a-3p, which was associated with pathways related to blood pressure and regulation of neurotransmission. In vitro norepinephrine downregulated miR-19a-3p. In conclusion, the T allele of the rs7194256 SNP in the 3'UTR of the NET gene is more prevalent in diseases where NET impairment is evident. This might be explained by the creation of a binding site for the microRNA miR-19a-3p. A defect in NET function may potentiate the sympathetic neurochemical signal, predisposing individuals with affective diseases to increased risk of cardiovascular disease development.


Assuntos
Proteínas da Membrana Plasmática de Transporte de Norepinefrina/genética , Regiões 3' não Traduzidas/genética , Adulto , Alelos , Sítios de Ligação , Doenças Cardiovasculares , Estudos de Coortes , Biologia Computacional , Transtorno Depressivo Maior/genética , Hipertensão Essencial , Feminino , Frequência Cardíaca , Humanos , Hipertensão/genética , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Norepinefrina/metabolismo , Proteínas da Membrana Plasmática de Transporte de Norepinefrina/metabolismo , Transtorno de Pânico/genética , Polimorfismo de Nucleotídeo Único/genética , Síndrome da Taquicardia Postural Ortostática/genética , População Branca/genética
8.
Scand J Med Sci Sports ; 27(12): 1942-1949, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28028840

RESUMO

Tendinopathy is a common condition, which has been linked to surrogate measures of sympathetic nervous system (SNS) activity and insulin resistance. This study aimed to compare in vivo measures of the SNS and insulin resistance between individuals with and without Achilles tendinopathy. This case-control study compared Achilles tendinopathy sufferers to healthy controls. SNS activity was quantified using muscle sympathetic nerve activity (MSNA), while metabolic status was assessed via a modified glucose tolerance test and fasting lipid panel. Ultrasound tissue characterization assessed tendon structure. Resting MSNA did not differ between the 15 cases and 20 controls. Tendon pain duration in tendinopathy patients was correlated with burst frequency (R2 =.32, P=.02) and burst incidence (R2 =.41, P=.01) of MSNA. After adjusting for multiple comparisons, there was a trend suggesting fasting glucose was greater in cases (median 4.80, IQR .70 in cases vs 4.51, .38 in controls) and correlated with pain severity (R2 =.14, P=.03), but no other metabolic measures were associated with tendon pain/structure. This study indicates that SNS activity is associated with tendon pain duration, building on previous data indicating the SNS is involved in recalcitrant tendinopathy. Metabolic parameters had little relationship with Achilles tendinopathy in this metabolically homogenous sample. Prospective studies are required to uncover the precise relationship between SNS activity, insulin resistance, and tendinopathy.


Assuntos
Tendão do Calcâneo/fisiopatologia , Resistência à Insulina , Dor/fisiopatologia , Sistema Nervoso Simpático/fisiopatologia , Tendinopatia/fisiopatologia , Tendão do Calcâneo/diagnóstico por imagem , Adulto , Estudos de Casos e Controles , Feminino , Teste de Tolerância a Glucose , Humanos , Masculino , Tendinopatia/diagnóstico por imagem , Ultrassonografia
9.
Ann Hum Biol ; 44(3): 208-213, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27546583

RESUMO

BACKGROUND: A double burden of both under- and over-nutrition exists among South African children. AIM: To describe associations between nutritional statuses and health-related fitness test performances. SUBJECTS AND METHODS: Height and weight of 10 285 children (6-13 years; n = 5604 boys and 4681 girls) were measured and used to calculate body mass index (BMI) and prevalence of overweight and obesity, stunting, wasting and underweight. Physical fitness scores for standing long jump, shuttle run, sit-and-reach, sit-up (EUROFIT) and cricket ball throw were assessed. Age- and gender-specific z-scores were calculated for these variables. Physical fitness for each nutritional status group was compared to children of normal weight. RESULTS: Compared to normal weight children, overweight and obese children scored lower on all fitness tests (p < .001), except cricket ball throw (p = .235) and sit-and-reach (p = .015). Stunted and underweight children performed poorer than normal weight children on most fitness tests (p < .001), except sit-and-reach (stunted: p = .829; underweight: p = .538) and shuttle run (underweight: p = .017). Performance of wasted children was not as highly compromised as other under-nourished groups, but they performed poorer on the cricket ball throw (p < .001). CONCLUSIONS: When compared to normal weight children, both under- and over-nourished children performed poorer on some, but not all, health-related fitness tests.


Assuntos
Estado Nutricional , Aptidão Física , Adolescente , Índice de Massa Corporal , Criança , Feminino , Transtornos do Crescimento/epidemiologia , Humanos , Masculino , Sobrepeso/epidemiologia , Obesidade Infantil/epidemiologia , Prevalência , África do Sul/epidemiologia , Magreza/epidemiologia
10.
Ear Hear ; 37(3): 334-44, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26684396

RESUMO

OBJECTIVES: It has long been speculated that effortful listening places children with hearing loss at risk for fatigue. School-age children with hearing loss experiencing cumulative stress and listening fatigue on a daily basis might undergo dysregulation of hypothalamic-pituitary-adrenal (HPA) axis activity resulting in elevated or flattened cortisol profiles. The purpose of this study was to examine whether school-age children with hearing loss show different diurnal salivary cortisol patterns than children with normal hearing. DESIGN: Participants included 32 children with mild to moderate hearing loss (14 males; 18 females) and 28 children with normal hearing (19 males; 9 females) ranging in age from 6 to 12 years. Saliva samples were obtained six times per day on two separate school days. Cortisol levels were measured by mass spectrometric detection after liquid-liquid extraction. Salivary cortisol levels between children with hearing loss and children with no hearing loss over the course of the day were examined with hierarchical linear modeling using mixed model statistical analysis. Between-group comparisons were also computed for the area under the curve, an analytical approach for calculating overall cortisol secretion throughout the day. RESULTS: Significant differences in the cortisol awakening response (CAR) were observed between children with hearing loss and children with normal hearing; however, no differences were observed between the two groups subsequent to the cortisol awakening response (60-min postawakening, 10:00 A.M., 2:00 P.M., and 8:00 P.M.). Compared with children with normal hearing, children with hearing loss displayed elevated cortisol levels at awakening and a reduced growth in cortisol secretion from awakening to 30-min postawakening. No significant differences in overall cortisol secretion throughout the day were found between groups (area under the curve). Finally, cortisol levels increased with increasing age for children with hearing loss but not for children with normal hearing. CONCLUSIONS: Results of this preliminary study indicate a possible dysregulation in HPA axis activity in children with hearing loss characterized by elevated salivary cortisol levels at awakening and a diminished increase in cortisol from awakening to 30-min postawakening. The pattern of elevated cortisol levels at awakening is consistent with some studies on adults with burnout, a condition characterized by fatigue, loss of energy, and poor coping skills. These findings support the idea that children with hearing loss may experience increased vigilance and need to mobilize energy promptly in preparation for the new day.


Assuntos
Fadiga/metabolismo , Perda Auditiva/metabolismo , Hidrocortisona/metabolismo , Saliva/química , Estresse Psicológico/metabolismo , Estudos de Casos e Controles , Criança , Fadiga/psicologia , Feminino , Perda Auditiva/psicologia , Humanos , Masculino , Índice de Gravidade de Doença , Estresse Psicológico/psicologia
11.
Diabetes Obes Metab ; 17(1): 91-3, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25200854

RESUMO

There is concern that intentional weight loss may generate excessive loss of fat-free mass (FFM). Idealists target minimal loss of FFM, while others consider that FFM loss of up to 25% of weight loss is acceptable. In a cross-sectional study of 275 weight-stable, overweight or obese adults, we used whole-body dual-energy X-ray absorptiometry to measure FFM. A range of models was used to estimate the expected ΔFFM/Δweight ratio required to attain the body composition of a weight-stable individual at a lower body mass index (BMI). Higher BMI was associated linearly with higher FFM in men and women. Proportional ΔFFM/Δweight was influenced by sex, BMI and age. Direct scatter plot analysis, quadratic curve fit modelling and linear FFM-BMI modelling provided similar estimates for each model of ΔFFM/Δweight ratio, with 40% for men and 33% for women. These results show that the 25% rule is inappropriate and our estimates are higher than those generally reported after intentional weight loss indicating favourable preservation of FFM.


Assuntos
Modelos Biológicos , Desenvolvimento Muscular , Atrofia Muscular/prevenção & controle , Obesidade/terapia , Sobrepeso/terapia , Redução de Peso , Absorciometria de Fóton , Adulto , Composição Corporal , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Atrofia Muscular/diagnóstico por imagem , Atrofia Muscular/etnologia , Atrofia Muscular/etiologia , Inquéritos Nutricionais , Obesidade/diagnóstico por imagem , Obesidade/etnologia , Sobrepeso/diagnóstico por imagem , Sobrepeso/etnologia , Caracteres Sexuais , Estados Unidos , Vitória , Redução de Peso/etnologia , População Branca , Imagem Corporal Total
12.
Exp Physiol ; 99(7): 985-94, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24803528

RESUMO

Microvascular dysfunction precedes the clinical manifestations of cardiovascular disease. Given the ethnic disparities in cardiovascular disease, we aimed to investigate ethnic differences in microvascular endothelial function in a group of young (18-33 years old), apparently healthy individuals (n = 33, nine Black African, 12 mixed ancestry and 12 Caucasian). Microvascular endothelium-dependent and -independent function was assessed by laser Doppler imagery and iontophoresis of ACh and sodium nitroprusside (SNP), respectively, adjusting for skin resistance. Microvascular reactivity was expressed as maximum absolute perfusion, percentage change from baseline and area under the curve (AUC). Skin resistance was significantly lower in the Caucasian group in response to ACh (Caucasian, mean 0.16 ± 0.03 Ω versus Black, 0.21 ± 0.04 Ω and mixed ancestry, 0.20 ± 0.02 Ω, P < 0.01) and SNP (Caucasian, 0.08 ± 0.01 Ω versus Black, 0.11 ± 0.02 Ω and mixed ancestry, 0.12 ± 0.01 Ω, P < 0.01). Microvascular function in response to ACh was significantly higher in the Caucasian group compared with the other two groups; however, after adjusting for skin resistance these differences were no longer significant. Conversely, the microvascular SNP response remained significantly higher in the Caucasian group, even after adjusting for skin resistance (P < 0.01). Diastolic blood pressure was inversely associated with the AUC of ACh (r = -0.4) and all SNP responses (r = -0.3 to -0.6). Skin resistance was inversely associated with AUC and maximum absolute ACh response (r = -0.59 and -0.64, respectively) and all SNP responses (r = -0.37 to -0.79). Ethnic differences in endothelium-independent microvascular function may contribute to ethnic disparities in cardiovascular disease. Moreover, skin resistance plays a significant role in the interpretation of the microvascular response to outcomes of iontophoresis in a multiethnic group.


Assuntos
Doenças Cardiovasculares/fisiopatologia , Endotélio Vascular/fisiologia , Microcirculação/fisiologia , Pele/irrigação sanguínea , Acetilcolina/administração & dosagem , Adulto , População Negra , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Impedância Elétrica , Feminino , Humanos , Iontoforese , Masculino , Nitroprussiato/administração & dosagem , Fenômenos Fisiológicos da Pele , África do Sul/epidemiologia , Vasodilatação/fisiologia , Adulto Jovem
13.
medRxiv ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38978669

RESUMO

Background: Freezing of gait (FOG) is a debilitating symptom of Parkinson's disease (PD) that is often refractory to medication. Pathological prolonged beta bursts within the subthalamic nucleus (STN) are associated with both worse impairment and freezing behavior in PD, which are improved with deep brain stimulation (DBS). The goal of the current study was to investigate the feasibility, safety, and tolerability of beta burst-driven adaptive DBS (aDBS) for FOG in PD. Methods: Seven individuals with PD were implanted with the investigational Summit™ RC+S DBS system (Medtronic, PLC) with leads placed bilaterally in the STN. A PC-in-the-loop architecture was used to adjust stimulation amplitude in real-time based on the observed beta burst durations in the STN. Participants performed either a harnessed stepping-in-place task or a free walking turning and barrier course, as well as clinical motor assessments and instrumented measures of bradykinesia, OFF stimulation, on aDBS, continuous DBS (cDBS), or random intermittent DBS (iDBS). Results: Beta burst driven aDBS was successfully implemented and deemed safe and tolerable in all seven participants. Gait metrics such as overall percent time freezing and mean peak shank angular velocity improved from OFF to aDBS and showed similar efficacy as cDBS. Similar improvements were also seen for overall clinical motor impairment, including tremor, as well as quantitative metrics of bradykinesia. Conclusion: Beta burst driven adaptive DBS was feasible, safe, and tolerable in individuals with PD with gait impairment and FOG.

14.
Int J Sports Med ; 34(7): 612-5, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23325715

RESUMO

Near infrared reactance (NIR) is used to measure body fat percentage (BF%), but there is little data on its use in non-obese, regularly exercising individuals. Therefore, this study aimed to examine the limits of agreement between NIR compared to dual x-ray absorptiometry (DXA) for the measurement of BF% in 2 cohorts of regularly exercising individuals. BF% was measured using DXA and NIR in a regular exercising (≥3 sessions/week), healthy active cohort (HA; n=57), and in a regularly exercising and resistance trained (≥2 sessions/week) cohort (RT; n=59). The RT cohort had lower BF% than the HA cohort (15.3±5.5% and 25.8±7.1%, P<0.001). In the HA and RT cohorts, NIR BF% was associated with DXA BF% (R2=0.72, SEE=3.7, p<0.001 and R2=0.50, SEE=4.1 p<0.001, respectively). In the HA cohort, NIR tended to under-predict BF% (mean difference: - 1.3%; 95% limits of agreement (LOA); - 8.8 to 6.2%) whereas in the RT cohort, NIR tended to over-predict BF% compared to DXA (mean difference: 1.1; 95% LOA; - 8.1 to 10.3%). In conclusion, NIR and DXA yield similar average BF% measurements in 2 cohorts of non-obese regularly exercising individuals. However, the rather broad LOA of NIR need to be considered when using NIR to screen for overweight and obesity, or measure and track changes in body composition.


Assuntos
Tecido Adiposo/fisiologia , Adiposidade/fisiologia , Composição Corporal/fisiologia , Treinamento Resistido/métodos , Absorciometria de Fóton/métodos , Adulto , Distribuição da Gordura Corporal , Estudos de Coortes , Exercício Físico/fisiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
15.
Opt Express ; 20(20): 22278-83, 2012 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-23037375

RESUMO

We propose a novel grating coupler design which is inherently reflectionless by focusing the reflected light away from the entrance waveguide. The design rules for this reflectionless grating coupler are explained and the grating coupler design is investigated by means of 3D FDTD simulations for the case of a Silicon-on-Insulator based platform.


Assuntos
Refratometria/instrumentação , Silício/química , Ressonância de Plasmônio de Superfície/instrumentação , Condutividade Elétrica , Desenho de Equipamento , Análise de Falha de Equipamento , Fótons , Integração de Sistemas
16.
J Exp Bot ; 63(2): 925-39, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22048039

RESUMO

Upon imbibition, dry seeds rapidly gain metabolic activity and the switching on of a germination-specific transcriptional programme in the nucleus goes ahead, with the induction of many nucleus-encoded transcripts coding for plastid-localized proteins. Dedifferentiated plastids present in dry seeds differentiate into chloroplasts in cotyledons and into amyloplasts in the root and in the hypocotyl, raising the question of whether the beginning of a new plant's life cycle is also characterized by specific changes in the plastid transcriptional programme. Here the plastid transcriptome is characterized during imbibition/stratification, germination, and early seedling outgrowth. It is shown that each of these three developmental steps is characterized by specific changes in the transcriptome profile, due to differential activities of the three plastid RNA polymerases and showing the integration of plastids into a germination-specific transcriptional programme. All three RNA polymerases are active during imbibition; that is, at 4 °C in darkness. However, activity of plastid-encoded RNA polymerase (PEP) is restricted to the rrn operon. After cold release, PEP changes specificity by also transcribing photosynthesis-related genes. The period of germination and radicle outgrowth is further characterized by remarkable antisense RNA production that diminishes during greening when photosynthesis-related mRNAs accumulate to their highest but to very different steady-state levels. During stratification and germination mRNA accumulation is not paralleled by protein accumulation, indicating that plastid transcription is more important for efficient germination than translation.


Assuntos
Arabidopsis/genética , Plastídeos/genética , Plântula/genética , Transcriptoma/genética , Arabidopsis/crescimento & desenvolvimento , Núcleo Celular/metabolismo , Cloroplastos/genética , Cotilédone/genética , Cotilédone/crescimento & desenvolvimento , Perfilação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento/genética , Regulação da Expressão Gênica de Plantas/genética , Germinação/genética , Hipocótilo/genética , Hipocótilo/crescimento & desenvolvimento , Análise de Sequência com Séries de Oligonucleotídeos , RNA Mensageiro/genética , RNA de Plantas/genética , Plântula/crescimento & desenvolvimento , Sementes/genética , Sementes/crescimento & desenvolvimento , Transcrição Gênica
17.
Osteoporos Int ; 23(2): 533-42, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21369790

RESUMO

SUMMARY: We examined ethnic differences in bone mineral density (BMD) and the contribution of body composition, lifestyle and socioeconomic factors in South African women. Femoral neck and total hip BMD were higher, but lumbar spine BMD was lower in black women, with body composition, lifestyle and socioeconomic status (SES) factors contributing differently in ethnic groups. INTRODUCTION: There is a paucity of data on the relative contribution of body composition, lifestyle factors and SES, unique to different ethnic groups in South Africa, to BMD. We examined differences in femoral neck (FN), total hip (TH) and lumbar spine (LS) BMD between black and white premenopausal South African women and the associations between BMD and body composition, lifestyle factors and SES in these two ethnic groups. METHODS: BMD and body composition were measured in 240 black (27 ± 7; 18-45 years) and 187 white (31 ± 8; 18-45 years) women using dual-energy X-ray absorptiometry. Questionnaires were administered to examine SES, physical activity and dietary intake. RESULTS: After co-varying for age, FN and TH were higher in black than white women (FN 0.882 ± 0.128 vs. 0.827 ± 0.116 g/cm(2), P < 0.001; TH 0.970 ± 0.130 vs. 0.943 ± 0.124 g/cm(2), P = 0.018). When adjusting for ethnic differences in body composition, LS was higher in white than black women. In black women, fat-free soft tissue mass, SES and injectable contraceptive use explained 33-42% of the variance in BMD at the hip sites and 22% at the LS. In white women, fat-free soft tissue mass and leisure activity explained 24-30% of the variance in BMD at the hip sites, whereas fat mass, leisure activity and oral contraceptive use explained 11% of the variance at the LS. CONCLUSION: FN and TH BMD were higher, but LS BMD was lower in black than white South African women with body composition, lifestyle and SES factors contributing differently to BMD in these women.


Assuntos
População Negra/estatística & dados numéricos , Densidade Óssea/fisiologia , Pré-Menopausa/etnologia , População Branca/estatística & dados numéricos , Adolescente , Adulto , Composição Corporal , Feminino , Colo do Fêmur/fisiologia , Articulação do Quadril/fisiologia , Humanos , Mediadores da Inflamação/metabolismo , Estilo de Vida , Vértebras Lombares/fisiologia , Pessoa de Meia-Idade , Atividade Motora/fisiologia , Pré-Menopausa/fisiologia , Saúde Reprodutiva , Fatores Socioeconômicos , África do Sul , Adulto Jovem
18.
Diabetes Obes Metab ; 14(2): 139-48, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21923735

RESUMO

AIM: Insulin resistance and visceral adiposity are predisposing factors for fatty liver disease. The main objectives of this study were (i) to compare the effects of caloric restriction (CR) alone or together with moderate-intensity aerobic exercise training (CR+EX) on liver enzymes, a surrogate marker of liver injury, in obese metabolic syndrome (MetS) subjects and (ii) to identify anthropometric, metabolic, cardiovascular and dietary predictors of changes in liver enzymes. METHODS: Sedentary men and women (n = 63), aged 55 ± 6 (s.d.) years with body mass index 32.7 ± 4.1 kg/m(2) and confirmed MetS, were randomized to 12-week CR, CR+EX or no treatment (Control). RESULTS: Weight loss averaged 7.6% in the CR and 9.1% in the CR+EX group (time effect, p < 0.001; group effect, p = 0.11); insulin sensitivity improved by 49 and 45%, respectively (both p < 0.001). Fitness (maximal oxygen consumption) increased by 19% in the CR+EX group only (p < 0.001). Alanine aminotransferase (ALT) levels decreased by 20% in the CR and 24% in the CR+EX group (time effect, both p < 0.001; group effect, p = 0.68); corresponding values for γ-glutamyltransferase (GGT) were -28 and -33%, respectively (time effect, both p < 0.001; group effect, p = 0.28). Reduction in abdominal fat mass (measured by DXA from L1 to L4) independently predicted ΔALT (r = 0.42, p = 0.005) and ΔGGT (r = 0.55, p < 0.001), whereas change in dietary saturated fat intake was independently associated with ΔALT (r = 0.35, p = 0.03). CONCLUSIONS: Reductions in central adiposity and saturated fat intake are key drivers of improvement in liver enzymes during lifestyle interventions. Exercise training did not confer significant incremental benefits in this study.


Assuntos
Alanina Transaminase/metabolismo , Restrição Calórica , Terapia por Exercício , Fígado Gorduroso/enzimologia , Fígado/enzimologia , Síndrome Metabólica/enzimologia , Obesidade/enzimologia , Redução de Peso , Idoso , Análise de Variância , Restrição Calórica/métodos , Tolerância ao Exercício , Feminino , Humanos , Masculino , Síndrome Metabólica/dietoterapia , Síndrome Metabólica/reabilitação , Pessoa de Meia-Idade , Obesidade/dietoterapia , Obesidade/reabilitação , Consumo de Oxigênio , Comportamento Sedentário
19.
S Afr J Sports Med ; 34(1): v34i1a13758, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36815935

RESUMO

Background: Anecdotal evidence suggests that athletes struggle to return to exercise post COVID-19 infection. However, studies evaluating the effect of COVID-19 on athletes' exercise activity are limited. Objectives: The objectives of this study were: (i) to describe the perceptions of recreational runners and cyclists recovering from COVID-19 on their training activity and general well-being, (ii) to compare device-measured training data in runners and cyclists pre- and post COVID-19, with non-infected controls that had a training interruption. Methods: Participants who were recruited via social media completed an online questionnaire (n=61), including demographic, health and COVID-19 descriptive data. In a sub-sample, device-measured training data (heart rate, time, distance and speed, n=27) were obtained from GPS devices for four weeks before infection and on resumption of training. Similar data were collected for the control group (n=9) whose training had been interrupted but by factors excluding COVID-19. Results: Most participants experienced a mild to moderate illness (91%) that was associated with a training interruption time of two-four weeks. Decreases in heart rate, relative exercise intensity, speed, time and distance were observed during the first week of returning to training for both groups, followed by an increase from Week two onwards. Discussion: Results failed to support a 'COVID-19 effect' on exercise activity as reductions in training variables occurred in both the COVID-19 and control groups. A possible explanation for the reductions observed is a deliberate gradual return to training by athletes post-COVID-19. Conclusion: More research is needed using device-measured training data prior to and post COVID-19 infection to better understand the impact of the SARS-CoV-2 virus on the exercise activity of athletes.

20.
S Afr Med J ; 112(8b): 639-648, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36458349

RESUMO

BACKGROUND: Physical activity is associated with a lower risk of cardiovascular outcomes, certain cancers and diabetes. The previous South African Comparative Risk Assessment (SACRA1) study assessed the attributable burden of low physical activity for 2000, but updated estimates are required, as well as an assessment of trends over time. OBJECTIVE: To estimate the national prevalence of physical activity by age, year and sex and to quantify the burden of disease attributable to low physical activity in South Africa (SA) for 2000, 2006 and 2012. METHODS: Comparative risk assessment methodology was used. Physical activity was treated as a categorical variable with four categories, i.e. inactive, active, very active and highly active. Prevalence estimates of physical activity levels, representing the three different years, were derived from two national surveys. Physical activity estimates together with the relative risks from the Global Burden of Disease, Injuries, and Risk Factors (GBD) 2016 study were used to calculate population attributable fractions due to inactive, active and very active levels of physical activity relative to highly active levels considered to be the theoretical minimum risk exposure (>8 000 metabolic equivalent of time (MET)-min/wk), in accordance with the GBD 2016 study. These were applied to relevant disease outcomes sourced from the Second National Burden of Disease Study to calculate attributable deaths, years of life lost, years lived with disability and disability adjusted life years (DALYs). Uncertainty analysis was performed using Monte Carlo simulation. RESULTS: The prevalence of physical inactivity (<600 METS) decreased by 16% and 8% between 2000 and 2012 for females and males, respectively. Attributable DALYs due to low physical activity increased between 2000 (n=194 284) and 2006 (n=238 475), but decreased thereafter in 2012 (n=219 851). The attributable death age-standardised rates (ASRs) declined between 2000 and 2012 from 60/100 000 population in 2000 to 54/100 000 population in 2012. Diabetes mellitus type 2 displaced ischaemic heart disease as the largest contributor to attributable deaths, increasing from 31% in 2000 to 42% in 2012. CONCLUSIONS: Low physical activity is responsible for a large portion of disease burden in SA. While the decreased attributable death ASR due to low physical activity is encouraging, this burden may be lowered further with an additional reduction in the overall prevalence of physical inactivity, in particular. It is concerning that the attributable burden for diabetes mellitus is growing, which suggests that existing non-communicable disease policies need better implementation, with ongoing surveillance of physical activity, and population- and community-based interventions are required in order to reach set targets.


Assuntos
Exercício Físico , Percepção Social , Feminino , Masculino , Humanos , África do Sul/epidemiologia , Fatores de Risco , Efeitos Psicossociais da Doença
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