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This research provides a review of seated shot put alongside new data from the Tokyo 2020 Paralympic Games with the aim to understand the latest trends in equipment within a recently established rule set and how key equipment variables may impact performance for athletes in different classifications. First, a review of the literature found that the throwing pole is a key equipment aid that is not well understood, in part due to limitations in testing design. New data from the 2020 Paralympic Games showed inconsistent trends for the use of the throwing pole among athletes, particularly in transitionary classes (F33-34 and F54-55). A two-way analysis of variance found a main effect of classification on performance (p < .001), as well as an interaction effect between pole use and classification on performance (p < .05). Notably, pole users are seen to perform better than non-pole users in Class F32 (p < .05).
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Rendimiento Atlético , Personas con Discapacidad , Deportes para Personas con Discapacidad , Humanos , Tokio , AtletasRESUMEN
This article summarises expert discussion on the management of patients with hepatocellular carcinoma (HCC), which took place during the 24th World Gastrointestinal Cancer Congress (WGICC) in Barcelona, July 2022. A multidisciplinary approach is mandatory to ensure an optimal diagnosis and staging of HCC, planning of curative and therapeutic options, including surgical, embolisation, ablative strategies, or systemic therapy. Furthermore, in many patients with HCC, underlying liver cirrhosis represents a challenge and influences the therapeutic options.
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Carcinoma Hepatocelular , Neoplasias Gastrointestinales , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/terapia , Neoplasias Gastrointestinales/diagnóstico , Neoplasias Gastrointestinales/terapia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/terapia , Guías de Práctica Clínica como AsuntoRESUMEN
Prediction of propulsion kinematics and performance in wheelchair sports has the potential to improve capabilities of individual wheelchair prescription while minimizing testing requirements. While propulsion predictions have been developed for daily propulsion, these have not been extended for maximal effort in wheelchair sports. A two step-approach to predicting the effects of changing set-up in wheelchair rugby was developed, consisting of: (One) predicting propulsion kinematics during a 5 m sprint by adapting an existing linkage model; and (Two) applying partial least-squares regression to wheelchair set-up, propulsion kinematics, and performance. Eight elite wheelchair rugby players completed 5 m sprints in nine wheelchair set-ups while varying seat height, seat depth, seat angle, and tire pressure. Propulsion kinematics (contact and release angles) and performance (sprint time) were measured during each sprint and used for training and assessment for both models. Results were assessed through comparison of predicted and experimental propulsion kinematics (degree differences) for Step One and performance times (seconds differences) for Step Two. Kinematic measures, in particular contact angles, were identified with mean prediction errors less than 5 degrees for 43 of 48 predictions. Performance predictions were found to reflect on-court trends for some players, while others showed weaker prediction accuracy. More detailed modeling approaches that can account for individual athlete activity limitations would likely result in improved accuracy in propulsion and performance predictions across a range of wheelchair sports. Although this would come at an increased cost, developments would provide opportunities for more suitable set-ups earlier in an athlete's career, increasing performance and reducing injury risk.
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Dam operations can affect mixing of the water column thereby influencing thermal heterogeneity spatially and temporally. This occurs by restricting or eliminating connectivity in longitudinal, lateral, vertical and temporal dimensions. We examined thermal heterogeneity across space and time and identified potential cold-water refuges for salmonids in a large impounded river in inland northwestern USA. To describe these patterns, we used thermal infrared (TIR) imagery, in situ thermographs, and high-resolution 3-D hydraulic mapping. We explained the median water temperature and probability of occurrence of cool-water areas using generalized additive models (GAMs) at reach and sub-catchment scales, and we evaluated potential cold-water refuge occurrence in relation to these patterns. We demonstrated that (1) lateral contributions from tributaries dominated thermal heterogeneity; (2) thermal variability at confluences was approximately an order of magnitude greater than of the main stem; (3) potential cold-water refuges were mostly found at confluences; and (4) the probability of occurrence of cool areas and median water temperature were associated with channel geomorphology and distance from dam. These findings highlight the importance of using multiple approaches to describe thermal heterogeneity in large impounded rivers and the need to incorporate these types of rivers in the understanding of thermal riverscapes because of their limited representation in the literature.
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Host-parasite systems have been models for understanding the connection between shifts in resource use and diversification. Despite theoretical expectations, ambiguity remains regarding the frequency and importance of host switches as drivers of speciation in herbivorous insects and their parasitoids. We examine phylogenetic patterns with multiple genetic markers across three trophic levels using a diverse lineage of geometrid moths (Eois), specialist braconid parasitoids (Parapanteles) and plants in the genus Piper. Host-parasite associations are mapped onto phylogenies, and levels of cospeciation are assessed. We find nonrandom patterns of host use within both the moth and wasp phylogenies. The moth-plant associations in particular are characterized by small radiations of moths associated with unique host plants in the same geographic area (i.e. closely related moths using the same host plant species). We suggest a model of diversification that emphasizes an interplay of factors including host shifts, vicariance and adaptation to intraspecific variation within hosts.
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Cadena Alimentaria , Interacciones Huésped-Patógeno/genética , Mariposas Nocturnas/genética , Mariposas Nocturnas/parasitología , Piper/genética , Árboles , Avispas/genética , Animales , Secuencia de Bases , Teorema de Bayes , Biología Computacional , Costa Rica , ADN Mitocondrial/genética , Ecuador , Evolución Molecular , Especiación Genética , Interacciones Huésped-Patógeno/fisiología , Larva/parasitología , Larva/fisiología , Modelos Genéticos , Datos de Secuencia Molecular , Mariposas Nocturnas/clasificación , Mariposas Nocturnas/fisiología , Filogenia , Análisis de Secuencia de ADN , Avispas/fisiologíaRESUMEN
BACKGROUND/OBJECTIVES: Data from human studies that have investigated the association between vitamin D status and cognitive function in elderly adults are conflicting. The objective of this study was to assess vitamin D status (reflected by serum 25-hydroxyvitamin D (25(OH)D)) in older European subjects (n=387; aged 55-87 years) and examine its association with measures of cognitive function. SUBJECTS/METHODS: Serum 25(OH)D was assessed using enzyme-linked immunosorbent assay, whereas measures of cognitive function were assessed using a comprehensive Cambridge Neuropsychological Testing Automated Battery (CANTAB). RESULTS: In all, 12, 36 and 64% of subjects had serum 25(OH)D concentrations <30, <50 and <80 nmol/l, respectively, throughout the year. Serum 25(OH)D was significantly and inversely correlated with four assessments within the spatial working memory (SWM) test parameter (SWM between errors (r=-0.166; P=0.003); SWM between errors 8 boxes (r=-0.134; P=0.038); SWM strategy (r=-0.246; P<0.0001); and SWM total errors (r=-0.174; P<0.003)). When subjects were stratified on the basis of tertiles (T) of serum 25(OH)D (<47.6 (T(1)); 47.6-85.8 (T(2)); and >85.8 (T(3)) nmol/l), fewer errors in SWM test scores occurred in subjects in the third T when compared with the first T (P<0.05-0.084). Stratification by sex showed that these differences between tertiles strengthened (P<0.001-0.043) in the females, but the differences were not significant (P>0.6) in males. CONCLUSIONS: Vitamin D insufficiency, but not deficiency, is widespread in the older population of several European countries. Low vitamin D status was associated with a reduced capacity for SWM, particularly in women.
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25-Hidroxivitamina D 2/sangre , Calcifediol/sangre , Trastornos del Conocimiento/epidemiología , Estado Nutricional , Deficiencia de Vitamina D/complicaciones , Anciano , Anciano de 80 o más Años , Envejecimiento , Cognición , Trastornos del Conocimiento/sangre , Trastornos del Conocimiento/complicaciones , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Trastornos de la Memoria/sangre , Trastornos de la Memoria/complicaciones , Trastornos de la Memoria/epidemiología , Memoria a Corto Plazo , Persona de Mediana Edad , Pruebas Neuropsicológicas , Factores de Riesgo , Índice de Severidad de la Enfermedad , Factores Sexuales , Deficiencia de Vitamina D/sangre , Deficiencia de Vitamina D/epidemiologíaRESUMEN
OBJECTIVE: To test Goldman's dilemma on a general population sample by asking whether they would take the Faustian bargain of a drug that guaranteed sporting success but would result in their death in 5 years' time. Between 1982 and 1995 a bi-annual survey using this dilemma suggested half of all elite athletes would take the drug. DESIGN: A random telephone survey of 250 members of the Australian general public, with counterbalanced presentation of success and death. MAIN OUTCOME MEASURES: Respondents gave age, gender, sports engagement and response to the dilemma (yes/no). RESULTS: Only two of a sample of 250 reported they would take the bargain offered by the dilemma. CONCLUSIONS: Athletes differ markedly from the general population in response to the dilemma. This raises significant practical and ethical dilemmas for athlete support personnel. The psychometry of the dilemma needs to be established more comprehensively for general and athlete populations.
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Atletas/psicología , Actitud Frente a la Salud , Doping en los Deportes/ética , Adulto , Anciano , Australia , Doping en los Deportes/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Opinión Pública , Adulto JovenAsunto(s)
Receptores de Activinas Tipo I/genética , Proteínas Portadoras/genética , Miositis Osificante/genética , Alelos , Mapeo Cromosómico , Cromosomas Humanos Par 2/genética , Análisis Mutacional de ADN , Tamización de Portadores Genéticos , Humanos , Mutación Missense , Reacción en Cadena de la Polimerasa , Valor Predictivo de las Pruebas , Terminología como AsuntoRESUMEN
OBJECTIVE: To assess the effects of zinc supplementation on vitamin status in middle-aged and older volunteers. SUBJECTS/METHODS: Three hundred and eighty-seven healthy middle-aged (55-70 years) and older (70-85 years) men and women, randomly allocated to three groups to receive 15 or 30 mg Zn/day or placebo for 6 months. Dietary intake was assessed by means of a validated 4-day recall record. Fasting blood samples were simultaneously analysed for levels of plasma retinol and alpha-tocopherol by high-performance liquid chromatography. Erythrocyte folates were measured by a competitive immunoassay with direct chemiluminescence detection on an automatized immunoanalyser. Biochemical measurements were performed at baseline and after 3 and 6 months of zinc supplementation. RESULTS: Plasma vitamin A levels were significantly increased proportionally with zinc dose and period of treatment, particularly at 6 months (for 15 mg Zn/day, P<0.05; for 30 mg Zn/day, P<0.0001); no significant changes were observed in the placebo group. There was no effect of zinc supplementation on vitamin E/cholesterol ratio and erythrocyte folates. CONCLUSIONS: Our results show that a long-term zinc supplementation increases plasma vitamin A levels in middle-aged and older people of similar characteristics to those involved in this study. Moreover, supplementation influences serum zinc levels but does not affect erythrocyte zinc concentration and both plasma vitamin E and erythrocyte folate status.
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Dieta , Estado Nutricional , Oligoelementos/administración & dosificación , Zinc/administración & dosificación , Zinc/sangre , Anciano , Anciano de 80 o más Años , Envejecimiento/fisiología , Cromatografía Líquida de Alta Presión/métodos , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Eritrocitos/química , Femenino , Ácido Fólico/sangre , Ácido Fólico/metabolismo , Humanos , Mediciones Luminiscentes/métodos , Masculino , Recuerdo Mental , Persona de Mediana Edad , Encuestas Nutricionales , Vitamina A/sangre , Vitamina E/sangreRESUMEN
BACKGROUND: CHARGE syndrome has an estimated prevalence of 1/10,000. Most cases are sporadic which led to hypotheses of a non-genetic aetiology. However, there was also evidence for a genetic cause with reports of multiplex families with presumed autosomal dominant, possible autosomal recessive inheritance and concordant twin pairs. We identified a monozygotic twin pair with CHARGE syndrome and a de novo balanced chromosome rearrangement t(8;13)(q11.2;q22). METHODS: Fluorescence in situ hybridisation was performed with BAC and PAC probes to characterise the translocation breakpoints. The breakpoint on chromosome 8 was further refined using 10 kb probes we designed and produced using sequence data for clone RP11 33I11, the Primer3 website, and a long range PCR kit. RESULTS: BAC and PAC probe hybridisation redefined the breakpoints to 8q12.2 and 13q31.1. Probe RP11 33I11 spanned the breakpoint on chromosome 8. Using our 10 kb probes we demonstrated that the chromodomain gene CHD7 was disrupted by the translocation between exons 3 and 8. DISCUSSION: Identifying that the translocation breakpoint in our patients occurred between exons 3 and 8 of CHD7 suggests that disruption of this gene is the cause of CHARGE syndrome in the twins and independently confirms the role of CHD7 in CHARGE syndrome.
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Anomalías Múltiples/genética , ADN Helicasas/genética , Proteínas de Unión al ADN/genética , Translocación Genética , Peso al Nacer , Bandeo Cromosómico , Cromosomas Humanos , Femenino , Genoma Humano , Humanos , Hibridación Fluorescente in Situ , Recién Nacido , Gemelos MonocigóticosRESUMEN
The porphyrias arise from predominantly inherited catalytic deficiencies of specific enzymes in heme biosynthesis. All genes encoding these enzymes have been cloned and several mutations underlying the different types of porphyrias have been reported. Traditionally, the diagnosis of porphyria is made on the basis of clinical symptoms, characteristic biochemical findings, and specific enzyme assays. In some cases however, these diagnostic tools reveal overlapping findings, indicating the existence of dual porphyrias with two enzymes of heme biosynthesis being deficient simultaneously. Recently, it was reported that the so-called Chester porphyria shows features of both variegate porphyria and acute intermittent porphyria. Linkage analysis revealed a novel chromosomal locus on chromosome 11 for the underlying genetic defect in this disease, suggesting that a gene that does not encode one of the enzymes of heme biosynthesis might be involved in the pathogenesis of the porphyrias. After excluding candidate genes within the linkage interval, we identified a nonsense mutation in the porphobilinogen deaminase gene on chromosome 11q23.3, which harbors the mutations causing acute intermittent porphyria, as the underlying genetic defect in Chester porphyria. However, we could not detect a mutation in the coding or the promotor region of the protoporphyrinogen oxidase gene that is mutated in variegate porphyria. Our results indicate that Chester porphyria is neither a dual porphyria, nor a separate type of porphyria, but rather a variant of acute intermittent porphyria. Further, our findings largely exclude the possibility that a hitherto unknown gene is involved in the pathogenesis of the porphyrias.
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Codón sin Sentido , Hidroximetilbilano Sintasa/genética , Porfiria Intermitente Aguda/genética , Secuencia de Bases , Análisis Mutacional de ADN , Ferredoxinas/genética , Flavoproteínas/genética , Humanos , Proteínas Mitocondriales/genética , Datos de Secuencia Molecular , Porfiria Intermitente Aguda/clasificación , Protoporfirinógeno-Oxidasa/genética , Succinato Deshidrogenasa/genéticaRESUMEN
The elderly are at nutritional risk as a result of multiple physiological, social, psychological, and economic factors. Physiological functions naturally decline with age, which may influence absorption and metabolism. Social and economic conditions can adversely affect dietary choices and eating patterns. However, at the same time, the nutrient needs of the elderly for certain nutrient (such as vitamins, minerals, proteins) is higher than for younger adults. This article reviews the importance of zinc (Zn) in elderly people, particularly for behavioural and mental function, micronutrient status, immune and antioxidant system, and bone metabolism.
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Envejecimiento/fisiología , Encuestas Nutricionales , Zinc , Anciano , Envejecimiento/inmunología , Envejecimiento/metabolismo , Antioxidantes/fisiología , Huesos/efectos de los fármacos , Huesos/metabolismo , Cognición/efectos de los fármacos , Cognición/fisiología , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Micronutrientes/deficiencia , Persona de Mediana Edad , Zinc/inmunología , Zinc/metabolismoRESUMEN
OBJECTIVE: To describe health and lifestyle factors of participants in the ZENITH study. DESIGN: A prospective multicentre intervention study employing a randomised double-blind design. PARTICIPANTS: Community dwelling older adults (n = 387), aged 55-87 y were recruited from regions in France, Italy and the UK. INTERVENTION: A self-report questionnaire comprising socio-demographic variables, dietary habits, physical activity in the home, at work and recreation. RESULTS: Participants differed with regards dietary habits and physical activity for each region. Recreational activity was higher in France and women generally tend to perform less hours of recreational activity per week than men. CONCLUSIONS: The differences found for these regions of Europe in relation to lifestyle factors will affect health and well-being within these countries and may mediate the impact of zinc supplementation on various biological and psychological parameters.
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Envejecimiento/fisiología , Estado de Salud , Estilo de Vida , Encuestas Nutricionales , Anciano , Método Doble Ciego , Europa (Continente) , Conducta Alimentaria/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Actividad Motora/fisiología , Estudios Prospectivos , Recreación/fisiología , Autorrevelación , Factores Sexuales , Factores Socioeconómicos , Encuestas y Cuestionarios , Factores de TiempoRESUMEN
OBJECTIVE: To assess the quality of positive and negative affect (mood) in an ageing European sample. BACKGROUND: Mood quality has important implications for both physical and mental wellbeing. Poor quality moods are associated with deficits in the diverse areas of cognitive function, health, and social relationships. The ageing process presents a number of potential challenges to successful mood regulation that could have wider implications. DESIGN AND PARTICIPANTS: The current study examines the quality of positive and negative affect in 387 healthy participants from three European countries. Moods were measured four times a day for 4-7 d with the Positive and Negative Affect Schedule (PANAS) mood scales. Measures of zinc (Zn) status were taken also. SETTING: Two centres concentrated on 55-70 yr olds (Coleraine, N.Ireland, n = 93 and Clermont-Ferrand, France, n = 95), and two centres concentrated on 70-87 yr olds (Rome, Italy, n = 108, and Grenoble, France, n = 91). RESULTS: Positive affect scores for the centre in Rome were significantly (P < 0.01) lower than for the other three centres, and the Grenoble centre had significantly (P < 0.05) higher scores on negative affect than the other three centres. Mood was not related to measures of zinc status (all Ps > 0.05). CONCLUSIONS: The two centres with the oldest participants showed deficits in mood quality that may have implications for broader well-being.
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Afecto/fisiología , Envejecimiento/psicología , Encuestas Nutricionales , Zinc/sangre , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Suplementos Dietéticos , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Psicometría , Valores de Referencia , Factores SexualesRESUMEN
BACKGROUND: Age-related decline in taste acuity may be both a cause and an effect of depleted zinc and/or increased zinc requirement. OBJECTIVE: The aim of this study was to explore associations between zinc status and taste acuity in healthy older European adults aged 55-90 y. SAMPLE: Volunteers were recruited within Italy (n = 108 aged 70-90 y), the United Kingdom (UK) (n = 93 aged 55-70) and two regions of France (n = 186), Grenoble (aged 70-90 y) and Clermont-Ferrand (aged 55-70 y). METHODS: A signal detection theory approach was adopted, employing a three-alternative, forced-choice procedure. The data were converted to R-indices and bivariate correlations were computed to explore relationships between serum zinc, erythrocyte zinc and taste acuity. ANOVA was undertaken to determine regional differences in zinc status. RESULTS: Higher erythrocyte zinc status was associated with better acuity for salt (sodium chloride) taste in the sample as a whole (P = 0.012) (n = 385). Higher serum zinc levels were associated with greater sensitivity to sour taste (citric acid) (P = 0.015) only in the older groups (aged 70-90 y). There were no apparent associations between serum or erythrocyte zinc status and acuity for bitter (quinine) or sweet (sucrose) tastes irrespective of age. CONCLUSION: These results agree with those previously suggesting that age-related detriment in sensitivity for salt taste may be associated with depleted zinc.
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Envejecimiento/fisiología , Encuestas Nutricionales , Estado Nutricional/fisiología , Gusto/fisiología , Zinc/sangre , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Eritrocitos/fisiología , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Valores de Referencia , Detección de Señal Psicológica/fisiología , Método Simple CiegoRESUMEN
OBJECTIVE: Inadequate intakes of micronutrients in elderly negatively affect the nutritional status. Zinc is an essential micronutrient in the elderly, especially in relation to its impact on immune function, bone mass, cognitive function and oxidative stress. However, data are lacking on zinc intake and status during normal ageing. In this study, we evaluate the intake and status of zinc in late middle-aged and older free-living subjects. DESIGN: Dietary zinc intake and zinc status in 188 middle-aged subjects from Clermont-Ferrand (Fr) and Coleraine (UK), and in 199 older subjects from Grenoble (Fr) and Roma (It) were assessed at the entry in the ZENITH study. RESULTS: In relation to the zinc RDA for people older than 55 y, zinc intakes in most of the middle-aged and older subjects (more than 96%) in the present study were adequate. Older people had significantly lower (P < 0.01) energy intakes as compared to middle-aged. Zinc intake expressed per MJ was also significantly (P < 0.01) higher in older people compared to middle-aged. Erythrocyte and urinary zinc concentrations were significantly (P < 0.001) higher in middle-aged subjects compared to older ones. The prevalence of biological Zn deficiency in free-living ageing European people was low (<5%). CONCLUSION: The results of the present study showed a relatively low prevalence of zinc deficiencies in healthy free-living late middle-age and older subjects. These results should be useful for health professionals to have reference data on zinc intake and status for a healthy ageing.
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Envejecimiento/fisiología , Encuestas Nutricionales , Estado Nutricional/fisiología , Zinc/administración & dosificación , Zinc/sangre , Factores de Edad , Anciano , Anciano de 80 o más Años , Análisis de Varianza , Ingestión de Energía/fisiología , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Valores de Referencia , Zinc/deficienciaRESUMEN
OBJECTIVE: To report selected dietary intake and vitamin status at baseline of volunteers participating in the ZENITH study and the correlation of vitamin status with zinc. DESIGN: A multicentre prospective intervention study employing a randomised double-blind design. SETTING: Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy). PARTICIPANTS: In total, 387 healthy middle-aged (55-70 y) and older (70-87 y) men and women participated in the study. METHODS: Dietary intake was assessed by means of a validated 4-d recall record. Fasting blood samples were simultaneously analysed for retinol and alpha-tocopherol by the HLPC method. Erythrocyte folates were measured by a competitive immunoassay with direct chemiluminescence detection on an automatised immunoanalyser. RESULTS: In all centres, men had a significantly (P < 0.0001) higher mean nutrient intake than women. Comparison between age-groups showed that older individuals had significantly lower intakes of macro- and selected micronutrients than middle-aged subjects (P < 0.0001). A high fat intake (from 36 to 40% of total energy) was observed in all examined groups. In relation to biochemical measures of vitamin status, all parameters were above their respective cut-off values for normality and, thus, none of the subjects had biochemical evidence of deficiency of these selected vitamins. A moderate correlation was found with plasma vitamin A and serum zinc (r = 0.12, P < 0.05) or red blood cell zinc (r = 0.12, P < 0.01) and with erythrocyte folates and red blood cell zinc (r = 0.11, P < 0.05). CONCLUSIONS: There were only moderate differences in the nutrient intake of the ZENITH study volunteers among the four European centres. Their biochemical status for retinol, alpha-tocopherol and folate appeared adequate.
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Ácido Fólico/administración & dosificación , Ácido Fólico/sangre , Estado Nutricional/fisiología , Vitamina A/administración & dosificación , Vitamina A/sangre , Vitamina E/administración & dosificación , Vitamina E/sangre , Factores de Edad , Anciano , Envejecimiento/fisiología , Cromatografía Líquida de Alta Presión/métodos , Registros de Dieta , Método Doble Ciego , Europa (Continente) , Femenino , Humanos , Mediciones Luminiscentes/métodos , Masculino , Persona de Mediana Edad , Encuestas Nutricionales , Estudios Prospectivos , Valores de Referencia , Factores SexualesRESUMEN
Zinc is known to be essential for a great number of biochemical activities and physiological and cognitive functions. The objective of Zenith study was to investigate the effects of Zn, as a nutritional supplement, on psychological and behavioural factors and on surrogate markers that are indicative of trends towards better health in order to evaluate the need for dietary recommendations specific to the studied population. We report in this paper the summary of baseline results obtained before Zn supplementation.
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Envejecimiento/fisiología , Micronutrientes , Encuestas Nutricionales , Zinc , Anciano , Envejecimiento/inmunología , Envejecimiento/metabolismo , Metabolismo Basal/efectos de los fármacos , Metabolismo Basal/fisiología , Huesos/efectos de los fármacos , Huesos/metabolismo , Cognición/efectos de los fármacos , Cognición/fisiología , Europa (Continente)/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estrés Oxidativo/efectos de los fármacos , Estrés Oxidativo/fisiología , Ensayos Clínicos Controlados Aleatorios como Asunto/estadística & datos numéricos , Hormonas Tiroideas/sangreRESUMEN
OBJECTIVE: This paper describes baseline data on basal metabolic rate (BMR), thyroid hormone levels and body composition of middle-aged and older people participating in the ZENITH project and the correlation of thyroid hormone levels with zinc status. DESIGN: A multicentre prospective intervention study employing a randomised double blind design. SETTING: Clermont-Ferrand, Theix (France), Coleraine (Northern Ireland), Grenoble (France), Rome (Italy). INTERVENTIONS: BMR has been measured on a subsample of 70 middle-aged volunteers (35 men and 35 women recruited in Clermont-Ferrand, France, aged 55-70 y) and 108 older volunteers (56 men and 52 women recruited in Rome, Italy, aged 70-85 y). Thyroid hormone levels were evaluated in the entire group of ZENITH volunteers (n = 387). BMR was measured by indirect calorimetry. Fat-free mass (FFM) was derived by four skinfold thicknesses using Durnin and Womersley's equations. Concentrations of thyroid hormones (total T3 and T4) were measured using a competitive immunoassay with an enhanced chemiluminescence end point. RESULTS: Italian older volunteers had a significantly lower FFM than middle-aged French volunteers (-7% P < 0.01). A negative correlation between BMR and age (men, r = -0.64; women, r = -0.62; both P < 0.0001) was observed: BMR was significantly (P < 0.000001) lower in Italian elderly volunteers (4.03+/-0.46 kJ/min and 3.29+/-0.42 kJ/min for men and women, respectively) than in middle-aged French volunteers (4.84+/-0.45 kJ/min and 3.87+/-0.38 kJ/min for men and women, respectively), even after adjustment for FFM (-12%). No correlation has been observed between BMR and thyroid hormones both in French and Italian subjects. Total T4 (TT4) concentrations were lowest in middle-aged population (-10%, P < 0.0001). A moderate negative correlation has been found with TT4 and red blood cell zinc (r = -0.12, P < 0.02, slope -0.026). CONCLUSIONS: The results confirm an age-related decline in BMR not entirely explained by body composition or thyroid hormones differences.
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Envejecimiento/fisiología , Metabolismo Basal/fisiología , Encuestas Nutricionales , Hormonas Tiroideas/sangre , Factores de Edad , Anciano , Análisis de Varianza , Composición Corporal/fisiología , Calorimetría Indirecta/métodos , Método Doble Ciego , Europa (Continente) , Femenino , Humanos , Mediciones Luminiscentes/métodos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores Sexuales , Grosor de los Pliegues Cutáneos , Zinc/sangreRESUMEN
OBJECTIVE: To determine zinc status and age-related changes in the immune function of healthy late-middle-aged men and women (aged 55-70 y). DESIGN: Observational study. SETTING: Population of Northern Ireland. SUBJECTS: Apparently healthy, free-living individuals (45 men, 48 women) aged 55-70 y. INTERVENTION: Zinc status markers were analysed by flame atomic absorption spectrometry and commercially available kits. Immune function was assessed by flow cytometry. RESULTS: Serum and erythrocyte zinc concentrations were 13.0 (s.d. 1.40) micromol/l and 222 (s.d. 48.2) micromol/l, respectively. Serum alkaline phosphatase (ALP) concentrations were 76.8 (s.d. 16.1) U/l; women showed significantly higher concentrations of ALP (P = 0.011). Women demonstrated (1) a significant inverse correlation in naive T lymphocytes, specifically naive T-helper lymphocytes (% expression, r = -0.364, P = 0.007 and absolute count, r = -0.275, P = 0.036) with age and (2) a significant positive correlation between late activation of T lymphocytes (% expression, r = 0.299, P = 0.019 and absolute count, r = 0.260, P = 0.039) with advancing age. Men demonstrated a significant positive correlation in the % expression of (CD3-/CD16+/CD56+) natural killer (NK) cells with age (r = 0.316, P = 0.017). CONCLUSIONS: Between the ages of 55 and 70 y, healthy individuals experience significant alterations in immune function; however, such changes appear largely sex specific. Given the reported importance of adequate zinc status in maintaining optimal immune function, further studies are required to explore the effect of enhanced zinc status on emerging immune deficiencies in cell-mediated immunity in healthy 55-70 y olds.