Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 16 de 16
Filtrar
Más filtros

Bases de datos
País/Región como asunto
Tipo del documento
Intervalo de año de publicación
1.
Eur J Nutr ; 62(3): 1093-1107, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36534178

RESUMEN

To summarize current knowledge and gaps regarding the role of postprandial glycaemic response in the paediatric population, a workshop was organized in June 2021 by the European branch of the International Life Science Institute (ILSI). This virtual event comprised of talks given by experts followed by in-depth discussions in breakout sessions with workshop participants. The main pre-specified topics addressed by the workshop organizing committee to the invited speakers and the workshop participants were: (1) the role of glycaemic responses for paediatric health, based on mechanistic insights from animal and human data, and long-term evidence from observational and intervention studies in paediatric populations, and (2) changes in metabolism and changes in dietary needs from infancy to adolescence. Each talk as well as the discussions were summarised, including the main identified research gaps. The workshop led to the consensus on the crucial role on health of postprandial glycaemic response in paediatric population. However, a lack of scientific data has been identified regarding detailed glucose and insulin profiles in response to foods commonly consumed by paediatric populations, as well as a lack of long-term evidence including the need for suitable predictors during childhood and adolescence to anticipate health effects during adulthood.


Asunto(s)
Glucemia , Dieta , Adolescente , Humanos , Niño , Adulto , Glucemia/metabolismo , Glucosa , Alimentos , Insulina , Periodo Posprandial , Índice Glucémico
2.
J Nutr ; 146(10): 2143-2148, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27581576

RESUMEN

BACKGROUND: Assessing skeletal muscle (SM) and visceral adipose tissue (VAT) by a single MRI slice at lumbar vertebra (L) 3 can replace whole-body MRI in young and middle-aged adults. However, this technique has not been proven in older adults. OBJECTIVE: The aim of this analysis was to reinvestigate the best estimate for SM and VAT in an independent population of healthy elderly people. METHODS: SM and VAT were assessed by whole-body MRI in 84 subjects ≥60 y [45 men; mean ± SD age: 68.4 ± 5.4 y, mean ± SD body mass index (in kg/m2): 25.5 ± 3.5]. SM and VAT areas of 9 slices at the lumbar spine were analyzed. The best estimate was investigated by Pearson correlations. Total volumes (in liters) were predicted by the area at lumbar vertebra 3 (AL3). Besides Bland-Altman analysis, linear regressions were performed to explain the variance of the bias by age, height, and percentage of fat mass (%FM). In a mixed population (healthy elderly plus reference population), linear regression with total SM and VAT volume as dependent variables and AL3, age, and height as independent variables was applied. RESULTS: When comparing the correlation coefficients between the tissue areas and total volumes, L3 was identified as the best estimate (r range: 0.71-0.94; all P < 0.05). However, Bland-Altman analysis showed a positive SM bias in men (mean ± SD: -1.0% ± 9.0%; P < 0.05) and a negative SM bias in women (mean ± SD: 3.7% ± 9.6%; P < 0.05). Contrary to SM, no significant bias was observed for VAT. In the elderly, stepwise linear regression showed height as a predictor for SM bias (R2 = 0.21, SEE = 2.07 L; P < 0.05) and %FM and age as predictors of the nonsignificant VAT bias (R2 = 0.26, SEE = 0.22L, P < 0.05), in men only. In the mixed population, AL3 and height were predictors for total SM, and AL3 for total VAT, independent of sex. CONCLUSIONS: AL3 was confirmed as the best estimate for SM and VAT volumes in healthy elderly adults. Contrary to VAT, there is a bias for SM, and height has to be added to the algorithm.


Asunto(s)
Grasa Intraabdominal/diagnóstico por imagen , Imagen por Resonancia Magnética , Músculo Esquelético/diagnóstico por imagen , Anciano , Anciano de 80 o más Años , Composición Corporal , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Modelos Lineales , Masculino , Persona de Mediana Edad
3.
Environ Sci Technol ; 49(5): 3211-8, 2015 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-25629730

RESUMEN

Large cities in the United States face multiple challenges in meeting federal air quality standards. One difficulty arises from the uncertainties in evaluating traffic-related air pollution, especially the formation of secondary pollutants such as ozone and some particulate matter. Current air quality models are not well suited to evaluate the impact of a short-term traffic change on air quality. Using regional traffic and ambient air quality data from Southern California, we examine the impact of a two-day freeway closure on traffic and several criteria air pollutants (CO, NO2, O3, PM10, PM2.5). The results indicate that regional traffic decreased about 14% on average during the closure. Daily average PM2.5 levels decreased by about 32%, and daily 8 h maximum ozone levels decreased by about 16%. However, the daily 1 h maximum NO2 concentration was higher at some sites during the closure. Despite the mixed results with NO2, this study provides empirical evidence to support traffic reduction as an effective strategy to address chronic air pollution problems, especially with regard to ozone, in Southern California.


Asunto(s)
Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/estadística & datos numéricos , Modelos Teóricos , Material Particulado/análisis , Transportes , Emisiones de Vehículos/análisis , Contaminantes Atmosféricos/normas , Monitoreo del Ambiente/métodos , Humanos , Los Angeles , Ozono/análisis
4.
Disasters ; 38(3): 587-609, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24905712

RESUMEN

When a no-notice emergency prompts an evacuation, family members in different locations throughout a city may unite so that they can evacuate as a group. This paper draws on data from more than 300 interviews conducted in the metropolitan area of Chicago, Illinois, United States. The study uses discrete choice models to analyse the expectations of respondents regarding whether their likely plans for evacuation involve gathering spouses, parents, adult-age children, and/or non-family members. In addition, it addresses the matter of whether respondents plan to reunite with family members at home. Individuals' access to a personal car is the dominating factor in predicting whether respondents plan to gather a spouse. Being the parent of a child under the age of 18 years increases the tendency to report planning to reunite with family members at home. Both commute mode and car availability are not significantly associated with plans to reunite at home.


Asunto(s)
Conducta de Elección , Planificación en Desastres/organización & administración , Urgencias Médicas , Composición Familiar , Relaciones Familiares , Adolescente , Adulto , Anciano , Chicago , Femenino , Humanos , Masculino , Persona de Mediana Edad , Modelos Psicológicos , Investigación Cualitativa , Adulto Joven
5.
Front Nutr ; 9: 829933, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35340549

RESUMEN

It is well-appreciated that the diet is a crucial tool to counteract cardiometabolic disturbances due to its impact on blood glucose concentration and gut microbiome. This retrospective analysis aimed to examine whether the inclusion of isomaltulose and prebiotic inulin-type fructans (ITF) into the habitual diet has an impact on glycemic control and gut microbiota. Furthermore, we examined interindividual differences in glycemic response to sugar replacement with isomaltulose. We retrospectively analyzed data of 117 individuals who participated in a digital nutrition program including a 14-day continuous glucose measurement. Participants underwent six test days with sweetened drinks (isomaltulose vs. sucrose) consumed with their usual breakfasts and lunches. Dinner was supplemented with ITF for 11 days. Postprandial glycemia and 24 h-glycemic variability were determined following test meals and days, respectively. Fecal microbiota was analyzed by 16S rRNA sequencing before and after test phase. Meals with isomaltulose-sweetened drinks compared to meals with sucrose-sweetened drinks induced lower postprandial glycemia. Moreover, glucose oscillations over 24 h were lower on isomaltulose when compared to sucrose test days and improved further during ITF supplementation. Furthermore, ITF modulated gut microbiota composition beneficially. Responder analysis revealed that 72% of participants benefited from the sugar replacement with isomaltulose and that their gut microbiota differed from the low responders. Taken together, the incorporation of isomaltulose and ITF into the habitual diet was shown to be an effective strategy to improve glucose control and beneficially modulate gut microbiota, and thereby aid to maintain metabolic health. Data indicate interindividual differences in glycemic response to ingredients and suggest that gut microbiota might be somehow related to it.

6.
Nutrients ; 12(1)2020 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-31947853

RESUMEN

Hyperglycemia is linked to impaired arterial endothelial function (EF), an early sign of cardiovascular disease. We compared the efficacy of low-glycemic index isomaltulose (Palatinose™) with that of sucrose in modulating EF, as assessed by flow-mediated dilation (FMD). In this double-blinded cross-over study, 80 overweight mildly hypertensive subjects were randomized to receive 50 g of either isomaltulose or sucrose. On two non-consecutive days, brachial artery ultrasound FMD scans were obtained prior to and hourly (T0-T3) after carbohydrate load. Blood was drawn immediately after scanning. Glucose and insulin levels were analyzed. Overall, the FMD decrease was attenuated by isomaltulose compared to sucrose (ΔFMD = -0.003% and -0.151%; p > 0.05 for the interaction treatment x period). At T2, FMD was significantly higher after isomaltulose administration compared to that after sucrose administration (FMD = 5.9 ± 2.9% and 5.4 ± 2.6%, p = 0.047). Pearson correlations between FMD and blood glucose showed a trend for a negative association at T0 and T2 independently of the carbohydrate (r-range = -0.20 to -0.23, p < 0.1). Sub-analysis suggested a lower FMD in insulin-resistant (IR) compared to insulin-sensitive subjects. Isomaltulose attenuated the postprandial decline of FMD, particularly in IR persons. These data support the potential of isomaltulose to preserve the endothelial function postprandially and consequently play a favorable role in cardiovascular health.


Asunto(s)
Sacarosa en la Dieta/administración & dosificación , Endotelio Vascular/efectos de los fármacos , Hemorreología/efectos de los fármacos , Isomaltosa/análogos & derivados , Sobrepeso/fisiopatología , Adulto , Glucemia/análisis , Arteria Braquial/diagnóstico por imagen , Arteria Braquial/fisiopatología , Estudios Cruzados , Método Doble Ciego , Endotelio Vascular/diagnóstico por imagen , Femenino , Índice Glucémico , Humanos , Hiperglucemia/etiología , Insulina/sangre , Isomaltosa/administración & dosificación , Masculino , Persona de Mediana Edad , Sobrepeso/sangre , Sobrepeso/complicaciones , Periodo Posprandial , Ultrasonografía
8.
Nutrients ; 11(10)2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-31590285

RESUMEN

Low-glycemic compared to high-glycemic diets have been shown to improve metabolic status and enhance fat oxidation. The randomized, double-blind, controlled intervention study aimed to evaluate the effects of an energy-reduced diet containing isomaltulose (ISO, Palatinose™) versus sucrose (SUC) on body weight loss. Sixty-four healthy overweight/obese adults were allocated to consume either 40g/d ISO or SUC added to an energy-reduced diet for 12 weeks. Anthropometric measurements, body composition, and energy metabolism were assessed at baseline and after 4, 8, and 12 weeks. Fifty participants (age: 40.7 ± 11.7 y; BMI: 29.4 ± 2.7 kg/m²) completed the study. During the 12 weeks, both groups significantly lost weight (p < 0.001), which was more pronounced following ISO (-3.2 ± 2.9 vs. -2.1 ± 2.6 kg; p = 0.258). Moreover, for participants in the ISO group, this was accompanied by a significant reduction in fat mass (ISO: -1.9 ± 2.5, p = 0.005; SUC: -0.9 ± 2.6%, p = 0.224). The overall decrease in energy intake was significantly higher in the ISO compared to that in the SUC group (p = 0.022). In addition, breakfast containing ISO induced a significantly lower increase in postprandial respiratory quotient (RQ) (mean incremental area under the curve (iAUC)2h for ISO vs. SUC: 4.8 ± 4.1 vs. 6.9 ± 3.1, p = 0.047). The results suggest that ISO in exchange for SUC may help to facilitate body weight reduction, lower postprandial RQ associated with higher fat oxidation, and reduce energy intake.


Asunto(s)
Restricción Calórica , Metabolismo Energético , Índice Glucémico , Isomaltosa/análogos & derivados , Obesidad/dietoterapia , Sacarosa/administración & dosificación , Pérdida de Peso , Adiposidad , Adulto , Método Doble Ciego , Inglaterra , Femenino , Humanos , Isomaltosa/administración & dosificación , Isomaltosa/efectos adversos , Isomaltosa/metabolismo , Masculino , Persona de Mediana Edad , Obesidad/diagnóstico , Obesidad/fisiopatología , Oxidación-Reducción , Sacarosa/efectos adversos , Sacarosa/metabolismo , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
9.
J Hazard Mater ; 156(1-3): 44-50, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-18294770

RESUMEN

Environmental justice advocates in the US and internationally have argued that hazardous materials industries are a source of significant community disruption and environmental hazard. Few of these studies, however, have examined firms' accident frequencies or how accidents are distributed across metropolitan regions. This research argues that accident frequencies differ significantly among firms, and they are an important part of understanding industries and their distribution within metropolitan regions. The accident records of the risk management plan (RMP) facilities in southern California provide an illustration for the discussion. Statistical tests demonstrate that previous accident counts correlate with future counts. The research heightens the usability of the existing accident record for local governments in the US.


Asunto(s)
Accidentes , Conservación de los Recursos Naturales/legislación & jurisprudencia , California , Modelos Teóricos , Gestión de Riesgos/organización & administración
10.
J Appl Physiol (1985) ; 124(1): 182-189, 2018 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-28751368

RESUMEN

Methods of body composition analysis are now widely used to characterize health status, i.e., nutritional status, metabolic rates, and cardiometabolic risk factors. However, the functional correlates of individual body components have not been systematically analyzed. In this study, we have used a two-compartment model, which was assessed by air displacement plethysmography. Detailed body composition was measured by whole body magnetic resonance imaging in a healthy population of 40 Caucasians, aged 65-81 yr (20 men; body mass index range: 18.6-37.2 kg/m2). Physical, metabolic, as well as endocrine functions included pulmonary function, handgrip strength, gait speed, sit-to-stand test, physical activity, blood pressure, body temperature, resting energy expenditure (REE), liver and kidney functions (glomerular filtration rate), insulin sensitivity [homeostasis model assessment (HOMA)], plasma lipids, plasma leptin, testosterone, dehydroepiandrosterone, insulin-like growth factor I levels, thyroid status, vitamins, and inflammation. Individual body compartments were intercorrelated, e.g., skeletal muscle mass (SM) correlated with visceral adipose tissue ( r = 0.53) and kidneys ( r = 0.62). For the functional correlates, SM ( r = 0.58) and liver volume ( r = 0.63) were associated with REE, SM correlated with handgrip strength ( r = 0.57), and kidneys with glomerular filtration rate ( r = 0.57). While visceral adipose tissue correlated with HOMA ( r = 0.59), subcutaneous adipose tissue was related to plasma leptin levels ( r = 0.84). The subcutaneous adipose tissue-to-leptin relationship was moderated by inflammation increasing the explained variance of leptin levels by 4.0%. In linear regression analysis, detailed body composition explained variances in REE (75.0%), HOMA (41.0%), and leptin (78.0%) compared with a body mass index-based model (REE 16.0%, HOMA 31.0%, leptin 45.0%). In addition, detailed body composition explained 39.0% of the variance in kidney function. NEW & NOTEWORTHY BCA should be used to address specific body functions only. In clinical practice, there is need of a clear focus on the specific research question related to physical, metabolic, or endocrine functions.


Asunto(s)
Composición Corporal , Evaluación Geriátrica , Imagen de Cuerpo Entero , Anciano , Anciano de 80 o más Años , Metabolismo Energético , Femenino , Fuerza de la Mano , Humanos , Inflamación , Resistencia a la Insulina , Leptina/sangre , Imagen por Resonancia Magnética , Masculino
11.
Clin Physiol Funct Imaging ; 37(2): 168-172, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26211898

RESUMEN

Dual-energy X-ray (DXA) is an alternative to magnetic resonance imaging (MRI) to measure skeletal muscle mass. DXA assesses lean body mass (LBM), and MRI measures skeletal muscle mass (SMM). Kim et al. (Am J Clin Nutr 2002; 76: 378; J Appl Physiol (1985) 2004; 97: 655) developed MRI-based algorithms to estimate whole-body SMM by DXA. These algorithms were based on an ethnically mixed study population (Kim et al., Am J Clin Nutr 2002; 76: 378; J Appl Physiol (1985) 2004; 97: 655). It is unclear whether Kim's algorithms are accurate in an exclusive Caucasian population. The aim of our study was to validate Kim's equation in a Caucasian population of 346 subjects. SMMMRI was assessed using MRI, and LBM and BMCDXA were measured by DXA and fat mass (FMADP ) by air-displacement plethysmographie (ADP). SMMMRI and predicted SMM were highly correlated (r = 0·944; P<0·05). The standard error of estimate of the regression equation was 2·4 kg. However, Bland-Altman plots showed a significant (P<0·001) systematic bias between SMMMRI (median 25·1 kg; IQ 20·2-31·1 kg) and predicted SMM (median 26·3 kg; IQ 22·6-33·0 kg), overestimating SMM by 9·8%. Multiple regression analyses showed that weight explained 4·4% of the variance in the differences between SMMMRI and predicted SMM with the major part unexplained. Kim's algorithm has a systematic unexplained bias and is not recommended in Caucasians.


Asunto(s)
Absorciometría de Fotón , Algoritmos , Imagen por Resonancia Magnética , Modelos Biológicos , Músculo Esquelético/diagnóstico por imagen , Población Blanca , Adiposidad/etnología , Adolescente , Adulto , Anciano , Índice de Masa Corporal , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pletismografía , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Adulto Joven
12.
J Gerontol A Biol Sci Med Sci ; 71(7): 941-6, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26590912

RESUMEN

BACKGROUND: The effect of gender as well as gender-specific changes of fat free mass (FFM) and its metabolic active components (muscle mass and organ masses [OMs]) and fat mass (FM) on age-related changes in resting energy expenditure (REE) are not well defined. We hypothesized that there are gender differences in (1) the age-specific onset of changes in detailed body composition (2); the onset of changes in body composition-REE associations with age. METHODS: Using a cross-sectional magnetic resonance imaging database of 448 Caucasian participants (females and males) with comprehensive data on skeletal muscle (SM) mass, adipose tissue (AT), OMs, and REE. RESULTS: We observed gender-specific differences in the onset of age-related changes in metabolic active components and REE. Declines in body composition and REE started earlier in females than in males for SM (29.4 vs 39.6 years), AT (38.2 vs 49.9 years), OM (34.7 vs 45.7 years), and REE (31.9 vs 36.8 years). The age-related decrease of AT was significantly higher in females than in males (-5.69kg/decade vs -0.59kg/decade). In females adjusted REEmFFM&FM (resting energy expenditure measured adjusted for FFM and FM) and REEmSM/OM/AT (resting energy expenditure measured adjusted for skeletal muscle and organ mass and adipose tissue) decreased by -145 kJ/d/decade and -604.8 kJ/d/ decade after the age of 35.2 respectively 34.3 years. SM was main determinant of REEm in females (R (2) = .67) and males (R (2) = .66) with remaining variance mainly explained by kidney mass (R (2) = .07) in females and liver mass (R (2) = .09) in males. CONCLUSION: We concluded that gender affects the age-related changes in body composition as well as changes in body composition-REE relationship. This trial was registered at linicaltrials.gov as NCT01737034.


Asunto(s)
Tejido Adiposo , Envejecimiento/fisiología , Composición Corporal/fisiología , Metabolismo Energético/fisiología , Riñón/patología , Hígado/patología , Músculo Esquelético , Tejido Adiposo/diagnóstico por imagen , Tejido Adiposo/metabolismo , Adulto , Edad de Inicio , Estudios Transversales , Femenino , Alemania/epidemiología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Músculo Esquelético/diagnóstico por imagen , Músculo Esquelético/metabolismo , Tamaño de los Órganos , Factores Sexuales
13.
Nutrients ; 8(6)2016 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-27258302

RESUMEN

Age-related changes in organ and tissue masses may add to changes in the relationship between resting energy expenditure (REE) and fat free mass (FFM) in normal and overweight healthy Caucasians. Secondary analysis using cross-sectional data of 714 healthy normal and overweight Caucasian subjects (age 18-83 years) with comprehensive information on FFM, organ and tissue masses (as assessed by magnetic resonance imaging (MRI)), body density (as assessed by Air Displacement Plethysmography (ADP)) and hydration (as assessed by deuterium dilution (D2O)) and REE (as assessed by indirect calorimetry). High metabolic rate organs (HMR) summarized brain, heart, liver and kidney masses. Ratios of HMR organs and muscle mass (MM) in relation to FFM were considered. REE was calculated (REEc) using organ and tissue masses times their specific metabolic rates. REE, FFM, specific metabolic rates, the REE-FFM relationship, HOMA, CRP, and thyroid hormone levels change with age. The age-related decrease in FFM explained 59.7% of decreases in REE. Mean residuals of the REE-FFM association were positive in young adults but became negative in older subjects. When compared to young adults, proportions of MM to FFM decreased with age, whereas contributions of liver and heart did not differ between age groups. HOMA, TSH and inflammation (plasma CRP-levels) explained 4.2%, 2.0% and 1.4% of the variance in the REE-FFM residuals, but age and plasma T3-levels had no effects. HMR to FFM and MM to FFM ratios together added 11.8% on to the variance of REE-FFM residuals. Differences between REE and REEc increased with age, suggesting age-related changes in specific metabolic rates of organs and tissues. This bias was partly explained by plasmaT3-levels. Age-related changes in REE are explained by (i) decreases in fat free mass; (ii) a decrease in the contributions of organ and muscle masses to FFM; and (iii) decreases in specific organ and tissue metabolic rates. Age-dependent changes in the REE-FFMassociation are explained by composition of FFM, inflammation and thyroid hormones.


Asunto(s)
Envejecimiento , Metabolismo Basal/fisiología , Composición Corporal/fisiología , Sobrepeso/metabolismo , Población Blanca , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
14.
J Autism Dev Disord ; 46(3): 1038-50, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26563948

RESUMEN

Low income Hispanic families experience multiple barriers to accessing evidence-based information on Autism Spectrum Disorders (ASD). This study utilized a mixed-strategy intervention to create access to information in published bio-medical research articles on ASD by distilling the content into parent-friendly English- and Spanish-language ASD Science Briefs and presenting them to participants using two socially-oriented dissemination methods. There was a main effect for short-term knowledge gains associated with the Science Briefs but no effect for the dissemination method. After 5 months, participants reported utilizing the information learned and 90% wanted to read more Science Briefs. These preliminary findings highlight the potential benefits of distilling biomedical research articles on ASD into parent-friendly educational products for currently underserved Hispanic parents.


Asunto(s)
Trastorno del Espectro Autista/etnología , Investigación Biomédica/métodos , Hispánicos o Latinos/etnología , Difusión de la Información/métodos , Padres/educación , Educación del Paciente como Asunto/métodos , Adolescente , Adulto , Trastorno del Espectro Autista/psicología , Trastorno del Espectro Autista/terapia , Femenino , Alfabetización en Salud/métodos , Hispánicos o Latinos/psicología , Humanos , Lenguaje , Masculino , Persona de Mediana Edad , Padres/psicología
15.
Cortex ; 64: 225-34, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25498947

RESUMEN

In digit-color synesthesia, a variant of grapheme-color synesthesia, digits trigger an additional color percept. Recent work on number processing in synesthesia suggests that colors can implicitly elicit numerical representations in digit-color synesthetes implying that synesthesia is bidirectional. Furthermore, morphometric investigations revealed structural differences in the parietal cortex of grapheme-color synesthetes, i.e., in the brain region where interactions between number and space occur in non-synesthetic subjects. Based upon these previous findings, we here examined whether implicitly evoked numerical representations interact with spatial representations in synesthesia in such a way that even a non-numerical, visuo-spatial task (here: line bisection) is modulated, i.e., whether synesthetes exhibit a systematic bisection bias for colored lines. Thirteen digit-color synesthetes were asked to bisect two sets of lines which were colored in their individual synesthetic colors associated with a small or a large digit, respectively. For all colored line stimuli combined, digit-color synesthetes showed--like control subjects (n = 13, matched for age, gender, IQ and handedness)--a pseudo-neglect when bisecting colored lines. Measuring the color-induced change of the bisection bias (i.e., comparing the biases when bisecting lines colored according to a small number vs those lines corresponding to a large number) revealed that only digit-color synesthetes were significantly influenced by line color. The results provide further evidence for the bidirectional nature of synesthesia and support the concept of a mental number line. In addition, they extend previous reports on bidirectionality in synesthesia by showing that even non-numerical, visuo-spatial performance can be modulated by implicit bidirectional processes.


Asunto(s)
Percepción de Color/fisiología , Reconocimiento Visual de Modelos/fisiología , Trastornos de la Percepción/fisiopatología , Percepción Espacial/fisiología , Adulto , Femenino , Humanos , Juicio/fisiología , Masculino , Pruebas Neuropsicológicas , Estimulación Luminosa , Tiempo de Reacción/fisiología , Sinestesia , Adulto Joven
16.
Am J Clin Nutr ; 102(1): 58-65, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26016860

RESUMEN

BACKGROUND: Whole-body magnetic resonance imaging (MRI) is the gold standard for the assessment of skeletal muscle (SM) and adipose tissue volumes. It is unclear whether single-slice estimates can replace whole-body data. OBJECTIVE: We evaluated the accuracy of the best single lumbar and midthigh MRI slice to assess whole-body SM, visceral adipose tissue (VAT), and subcutaneous adipose tissue (SAT). DESIGN: Whole-body MRI was performed in 142 healthy adults aged 19-65 y [mean ± SD age: 37.0 ± 11.8 y; BMI (in kg/m(2)): 25.3 ± 5.9]. Single slices were taken at lumbar vertebrae L1-L5 plus intervertebral discs and the thigh (midthigh, 10 cm distally from the midthigh, and 10 cm proximally from the midthigh). The value of single-slice areas was also tested in a longitudinal study on 48 healthy volunteers during weight loss (8.2 ± 5.2 kg). RESULTS: Cross-sectionally, all SM and adipose tissue single-slice areas correlated with total tissue volumes (P < 0.01). Because of the close associations between L3 areas and corresponding tissue volumes (r = 0.832-0.986, P < 0.01), this location was identified as the reference to estimate SM and adipose tissue in both sexes. SM, SAT, and VAT areas at L3 explained most of the variance of total tissue volumes (69-97%, with SEs of estimation of 1.96 and 2.03 L for SM, 0.23 and 0.61 L for VAT, and 4.44 and 2.47 L for SAT for men and women, respectively. There was no major effect on the explained variance compared with that for optimal slices. For SM, the optimal slice area was shown at midthigh. With weight-loss changes in total SM, VAT, and SAT, volumes were significantly different from those at baseline (SM changes: -2.8 ± 2.9 L; VAT changes: -0.7 ± 1.0 L; SAT changes: -5.1 ± 6.0 L). The area at L3 reflected changes in total VAT and SAT. To assess changes in total SM volumes, areas at midthigh showed the best evidence. CONCLUSION: In both sexes, a single MRI scan at the level of L3 is the best compromise site to assess total tissue volumes of SM, VAT, and SAT. By contrast, L3 does not predict changes in tissue components. This trial was registered at clinicaltrials.gov as NCT01737034.


Asunto(s)
Tejido Adiposo/ultraestructura , Imagen por Resonancia Magnética/métodos , Músculo Esquelético/ultraestructura , Adulto , Anciano , Composición Corporal , Índice de Masa Corporal , Estudios Transversales , Femenino , Voluntarios Sanos , Humanos , Modelos Lineales , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Pérdida de Peso , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA