143 resultados para dietary pattern
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More than one hundred years ago the "protein hypothesis" of the pathogenesis of atherosclerosis and its association with cardiovascular disease was put forward on the basis of animal experiments; however, it has so far never been verified in humans. This theory was soon replaced by the "lipid hypothesis", which was confirmed in humans as of 1994. Epidemiological ecological studies in the 1960 s showed significant associations between dietary animal protein and mortality from cardiovascular disease. However, animal protein intake was also significantly correlated with saturated fatty acid and cholesterol intake. In the last decades two prospective cohort studies demonstrated a decreased cardiovascular risk in women during high- versus low-protein intake when adjusting for other dietary factors (e. g., saturated fats) and other cardiovascular risk factors. A direct cholesterol lowering effect of proteins has not been shown. Despite earlier research indicating that soy protein has cardioprotective effects as compared to other proteins, these observations have not been confirmed by randomized placebo-controlled trials. However, most experts recommend the consumption of foods rich in plant proteins as alternatives to meat and dairy products rich in saturated fat and containing cholesterol. There are no scientific arguments to increase the daily protein intake to more than 20 % of total energy intake as recommended by the guidelines, in order to improve cardiovascular health.
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1. The importance of dietary lipids for carotenoid-based ornaments has rarely been investigated, although theory predicts that dietary lipids may control the development of these widespread animal signals. Dietary lipids have been suggested to enhance the expression of male carotenoid-based ornaments because they provide carotenoids with a hydrophobic domain that facilitates their absorption and transport. Dietary lipids may also enhance the uptake of tocopherols (vitamin E), which share common absorption and transport routes with carotenoids. Here, we test whether dietary lipids enhance carotenoid availability and male carotenoid-based colorations. We also explore the effects of dietary lipids on plasma tocopherol concentration, which allow disentangling between different pathways that may explain how dietary lipids affect ornamental expression. 2. Following a two-factorial design, we manipulated dietary access of naturally occurring fatty acids (oleic acid) and carotenoids (lutein and zeaxanthin) and measured its effects on the circulating concentrations of carotenoids (lutein and zeaxanthin) and vitamin E (α- and γ-(β-) tocopherols) and on the ventral, carotenoid-based coloration of male common lizards (Lacerta vivipara). 3. Lutein but not zeaxanthin plasma concentrations increased with carotenoid supplementation, which, however, did not affect coloration. Lipid intake negatively affected circulating concentrations of lutein and γ-(β-) tocopherol and led to significantly less orange colorations. The path analysis suggests that a relationship between the observed colour change and the change in plasma concentrations of γ-(β-) tocopherol may exist. 4. Our study shows for the first time that dietary lipids do not enhance but reduce the intensity of male carotenoid-based ornaments. Although dietary lipids affected plasma carotenoid concentration, its negative effect on coloration appeared to be linked to lower vitamin E plasma concentrations. These findings suggest that a conflict between dietary lipids and carotenoid and tocopherol uptake may arise if these nutrients are independently obtained from natural diets and that such conflict may reinforce signal honesty in carotenoid-based ornaments. They also suggest that, at least in the common lizard, sexual selection with respect to carotenoid-based coloration may select for males with low antioxidant capacity and thus for males of superior health.
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Résumé Interaction entre les lipides alimentaires et l'inactivité physique sur la sensibilité à l'insuline et les lipides intramyocellulaires chez le sujet masculin en bonne santé Ces deux dernières décennies, l'incidence de la résistance à l'insuline n'a cessé de progresser dans les pays industrialisés. Un grand nombre de travaux suggèrent que ce trouble métabolique joue un rôle important dans la pathogenèse de maladies propres au monde industrialisé, telles que le diabète, l'hypertension et les maladies cardiovasculaires. Malgré de nombreuses études, les mécanismes à l'origine de la résistance à l'insuline restent encore incomplètement élucidés. En plus d'une composante génétique, de nombreux facteurs environnementaux semblent impliqués parmi ces derniers, nous nous sommes intéressés à l'effet d'une alimentation riche en graisses associée à une période d'inactivité physique de courte durée. Nous nous sommes également penchés sur la corrélation décrite entre la résistance à l'insuline et la concentration de graisses présentes à l'intérieur des cellules musculaires squelettiques, appelées lipides intramyocellulaires. Pour ce faire, 8 volontaires masculins ont été étudiés à deux occasions. Après deux jours de diète équilibrée associée à une activité physique, les participants étaient confinés au lit strict pour 60 heures et devaient manger une alimentation soit riche en graisses saturées soit riche en hydrates de carbones. Pour évaluer l'effet de l'alimentation seule, 6 des 8 volontaires ont été réétudiés après deux jours de diète équilibrée suivie par 60 heures d'alimentation riche en graisses saturées associées à une activité physique contrôlée. Nous avons estimé la sensibilité à l'insuline par la technique du clamp hyperinsulinémique euglycémique alors que la concentration de lipides intramyocellulaires a été déterminée par spectroscopie par résonance magnétique. Après 60 heures d'inactivité physique associée à une alimentation riche en lipides, nous avons observé une diminution de l'utilisation de glucose dépendante de l'insuline (-24±6%; p<0.05), alors qu'aucune modification significative de ce même paramètre n'a été constatée lorsque l'inactivité physique était associée à une alimentation riche en hydrates de carbones (+19±10%). Ces deux conditions se sont accompagnées d'une augmentation des lipides intramyocellulaires (+32±7% et +17±8% respectivement). Bien que l'augmentation des lipides intramyocellulaires observée après 60 heures d'une alimentation riche en graisses saturées associée à une activité physique modérée fût d'une ampleur similaire à celle de la condition associant une alimentation riche en graisses et inactivité physique, l'utilisation de glucose induite par l'insuline n'a pas été modifiée de manière significative (-7±9%) Ces résultats indiquent que l'inactivité physique et une alimentation riche en graisses saturées semblent interagir, induisant une diminution de la sensibilité à l'insuline globale. La concentration de lipides intramyocellulaires a été influencée par les lipides issus de l'alimentation et l'inactivité physique, sans être toutefois corrélée à la résistance à l'insuline. Abstract OBJECTIVE - To assess the effect of a possible interaction between dietary fat and physical inactivity on whole-body insulin sensitivity and intramyocellular lipids (IMCLs). RESEARCH DESIGN AND METHODS - Eight healthy male volunteers were studied on two occasions. After 2 days of an equilibrated diet and moderate physical activity, participants remained inactive (bed rest) for 60 h and consumed either a high-saturated fat (45% fat, of which ~60% was saturated fat [BR-HF]) or a high-carbohydrate (70% carbohydrate [BR-HCHO]) diet. To evaluate the effect of a high-fat diet alone, six of the eight volunteers were restudied after a 2-day equilibrated diet followed by 60 h on a high-saturated fat diet and controlled physical activity (PA-HF). Insulin sensitivity was measured by hyperinsulinemic-euglycemic clamp and IMCL concentrations by H-magnetic resonance spectroscopy. RESULTS - Insulin-mediated glucose disposal was decreased by BR-HF condition (-24 ± 6%, P < 0.05) but did not change with BR-HCHO ( + 19 ± 10%, NS). BR-HF and BR-HCHO increased IMCL levels (+32 ± 7%, P < 0.05 and +17 ± 8%, P < 0.0011, respectively). Although the increase in IMCL levels with PA-HF (+31 ± 19%, P = 0.12) was similar to that during BR-HF, insulin-mediated glucose disposal ( -7 ± 9%, NS) was not decreased. CONCLUSIONS - These data indicate that physical inactivity and a high-saturated fat diet may interact to reduce whole-body insulin sensitivity. IMCL content was influenced by dietary lipid and physical inactivity but was not directly associated with insulin resistance.
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Current research on sleep using experimental animals is limited by the expense and time-consuming nature of traditional EEG/EMG recordings. We present here an alternative, noninvasive approach utilizing piezoelectric films configured as highly sensitive motion detectors. These film strips attached to the floor of the rodent cage produce an electrical output in direct proportion to the distortion of the material. During sleep, movement associated with breathing is the predominant gross body movement and, thus, output from the piezoelectric transducer provided an accurate respiratory trace during sleep. During wake, respiratory movements are masked by other motor activities. An automatic pattern recognition system was developed to identify periods of sleep and wake using the piezoelectric generated signal. Due to the complex and highly variable waveforms that result from subtle postural adjustments in the animals, traditional signal analysis techniques were not sufficient for accurate classification of sleep versus wake. Therefore, a novel pattern recognition algorithm was developed that successfully distinguished sleep from wake in approximately 95% of all epochs. This algorithm may have general utility for a variety of signals in biomedical and engineering applications. This automated system for monitoring sleep is noninvasive, inexpensive, and may be useful for large-scale sleep studies including genetic approaches towards understanding sleep and sleep disorders, and the rapid screening of the efficacy of sleep or wake promoting drugs.
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In celiac disease, enhanced permeability to gliadin peptides can result from their apico-basal transport by secretory immunoglobulin A1 (SIgA1) binding to the CD71 receptor ectopically expressed at the gut epithelial surface. Herein, we have established a mouse model in which there is apico-basal transport of the model antigen ovalbumin (OVA) by specific SIgA1 and have analyzed local T-cell activation. Transgenic DO11.10 mice were grafted with a hybridoma-secreting OVA-specific humanized IgA1, which could bind mouse CD71 and which were released in the intestinal lumen as SIgA. CD71 expression was induced at the gut apical surface by treating the mice with tyrphostin A8. Following gavage of the mice with OVA, OVA-specific CD4(+) T cells isolated from the mesenteric lymph nodes displayed higher expression of the activation marker CD69 and produced more interferon gamma in mice bearing the hybridoma-secreting OVA-specific IgA1, than in ungrafted mice or in mice grafted with an irrelevant hybridoma. These results indicate that the protective role of SIgA1 might be jeopardized in human pathological conditions associated with ectopic expression of CD71 at the gut surface.
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On the basis of MRI examinations in 88 neonates and infants with perinatal asphyxia, we defined 6 different patterns on T2-weighted images: pattern A--scattered hyperintensity of both hemispheres of the telencephalon with blurred border zones between cortex and white matter, indicating diffuse brain injury; pattern B--parasagittal hyperintensity extending into the corona radiata, corresponding to the watershed zones; pattern C--hyper- and hypointense lesions in thalamus and basal ganglia, which relate to haemorrhagic necrosis or iron deposition in these areas; pattern D--periventricular hyperintensity, mainly along the lateral ventricles, i.e. periventricular leukomalacia (PVL), originating from the matrix zone; pattern E--small multifocal lesions varying from hyper--to hypointense, interpreted as necrosis and haemorrhage; pattern F--periventricular centrifugal hypointense stripes in the centrum semiovale and deep white matter of the frontal and occipital lobes. Contrast was effectively inverted on T1-weighted images. Patterns A, B and C were found in 17%, 25% and 37% of patients, and patterns D, E and F in 19%, 17% and 35%, respectively. In 49 patients a combination of patterns was observed, but 30% of the initial images were normal. At follow-up, persistent abnormalities were seen in all children with patterns A and D, but in only 52% of those with pattern C. Myelination was retarded most often in patients with diffuse brain injury and PVL (patterns A and D).
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Introduction: The assessment of dietary intake by examination is a tool that allows knowing the habits and detecting certain nutritional deficiencies. Thus, it is essential in chronic disease and especially in children, where deficiencies can have a negative impact on growth and pubertal development. Objectives: Compare the dietary intake between children with inflammatory bowel disease (IBD) and healthy controls. Methods: Twenty-nine healthy controls (12 girls; mean age: 12.7 ± 1.9 years) and 21 IBD patients (11 girls; 14.3 ± 1.3 years) recruited from August 2011 to October 2012. Dietary intake was assessed by 24h recall. Results: No differences were found between IBD patients and healthy controls regarding dietary intake (table). Both IBD patients and healthy controls had excessive protein consumption. Furthermore, there are deficiencies for some nutriments (fibers, calcium and magnesium). Qualitative analysis revealed that both, IBD patients and healthy controls showed increased snacking and bad lipids distribution, especially for saturated lipids. Conclusion: Both children with IBD and health controls have a food imbalance and a low intake of minerals and vitamins. No differences between children with IBD and healthy controls were found.
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We present a new approach for analyzing the turnover rates of Cretaceous radiolarians recorded in pelagic sequences of western Tethys, The analysis of major extinction-radiation events and the fluctuation of diversity are compared with major paleoceanographic events and variation of diversity in dinoflagellates, calcareous nannoplankton and ammonites. There is an extraordinary correlation between biotic changes and sea level changes, temperatures, O, C and Sr isotopes, phosphorus accumulation rates and anoxic episodes. This reveals a predominantly abiotic control on the evolution of radiolarians. The rate of turnover and the diversity through time of two major orders of radiolarians (nassellarians and spumellarians) exhibits (1) the quasi-parallelism of their diversity curves, excluding a direct competition between them, (2) greater resistance of spumellarians to extinction during the early stage of extinction intervals and (3) a stronger post-extinction recovery of nassellarians. Evolutionary rates of radiolarians can be a good means of monitoring global environmental changes and allowing us to understand more clearly the relationship between plankton evolution, climate and pale oceanographic processes.
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PURPOSE OF REVIEW: The prevalence of nonalcoholic fatty liver disease is increasing worldwide and there is strong evidence that dietary factors play a role in its pathogenesis. The present review aims to provide a better understanding of how carbohydrates and other macronutrients may affect the disease. RECENT FINDINGS: The effects of carbohydrates on the development of nonalcoholic fatty liver disease differ depending upon the carbohydrate type; high-glycemic index foods are related to increased hepatic fat in both rodents and humans. Similarly, simple carbohydrates, such as fructose, stimulate hepatic de-novo lipogenesis and decrease lipid oxidation, thus leading to increased fat deposition. The underlying mechanisms may involve the activation of transcription factors. Fat intake broadly leads to hepatic fat deposition in rodents but few data are available on humans. Both carbohydrates and fat trigger inflammatory factors, which are closely related to metabolic disorders and nonalcoholic fatty liver disease. Lifestyle interventions appear to be the most appropriate first-line treatment for nonalcoholic fatty liver disease. SUMMARY: There is strong evidence that the diet may affect the development of nonalcoholic fatty liver disease. Although simple carbohydrates are clearly shown to have deleterious effects in humans, the role of fat remains controversial. Further studies will be required to evaluate the effects of macronutrient composition on the development of nonalcoholic fatty liver disease.
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We diagnosed a non-small cell lung carcinoma in a 49-year-old female patient with the histopathological diagnosis of stage IIIB mixed bronchioloalveolar and papillary adenocarcinoma with extensive micropapillary feature, which was not visualized on the preoperative multimodality imaging with positron emission tomography (PET) and computed tomography (CT). The micropapillary component characterized by a unique growth pattern with particular morphological features can be observed in all subtypes of lung adenocarcinoma. Micropapillary component is increasingly recognized as a distinct entity associated with higher aggressiveness. Even the most modern multimodality PET/CT imaging technology may fail to adequately visualize this important component with highly relevant prognostic implications. Thus, the pathologist needs to consciously look for a micropapillary component in the surgical specimen or in preoperative biopsies or cytology. This may have potential future treatment implications, as adjuvant or neoadjuvant chemotherapy may be of relevance, even in the early stages of the disease.
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In a biophysical approach to the study of swimming performance (blending biomechanics and bioenergetics), inter-limb coordination is typically considered and analysed to improve propulsion and propelling efficiency. In this approach, 'opposition' or 'continuous' patterns of inter-limb coordination, where continuity between propulsive actions occurs, are promoted in the acquisition of expertise. Indeed a 'continuous' pattern theoretically minimizes intra-cyclic speed variations of the centre of mass. Consequently, it may also minimize the energy cost of locomotion. However, in skilled swimming performance there is a need to strike a delicate balance between inter-limb coordination pattern stability and variability, suggesting the absence of an 'ideal' pattern of coordination toward which all swimmers must converge or seek to imitate. Instead, an ecological dynamics framework advocates that there is an intertwined relationship between the specific intentions, perceptions and actions of individual swimmers, which constrains this relationship between coordination pattern stability and variability. This perspective explains how behaviours emerge from a set of interacting constraints, which each swimmer has to satisfy in order to achieve specific task performance goals and produce particular task outcomes. This overview updates understanding on inter-limb coordination in swimming to analyse the relationship between coordination variability and stability in relation to interacting constraints (related to task, environment and organism) that swimmers may encounter during training and performance.
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Dietary obesity is a major factor in the development of type 2 diabetes and is associated with intra-adipose tissue hypoxia and activation of hypoxia-inducible factor 1α (HIF1α). Here we report that, in mice, Hif1α activation in visceral white adipocytes is critical to maintain dietary obesity and associated pathologies, including glucose intolerance, insulin resistance, and cardiomyopathy. This function of Hif1α is linked to its capacity to suppress β-oxidation, in part, through transcriptional repression of sirtuin 2 (Sirt2) NAD(+)-dependent deacetylase. Reduced Sirt2 function directly translates into diminished deacetylation of PPARγ coactivator 1α (Pgc1α) and expression of β-oxidation and mitochondrial genes. Importantly, visceral adipose tissue from human obese subjects is characterized by high levels of HIF1α and low levels of SIRT2. Thus, by negatively regulating the Sirt2-Pgc1α regulatory axis, Hif1α negates adipocyte-intrinsic pathways of fatty acid catabolism, thereby creating a metabolic state supporting the development of obesity.
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Dietary acid load from Western diets may be a risk factor for osteoporosis. It can be estimated by net endogenous acid production (NEAP). No data currently exists for NEAP estimates and bone indices in the very elderly (i.e. > or = 75 y). The aim of this study was to determine the association between NEAP estimates by using the potential renal acid load (PRAL) equation and quantitative bone ultrasound (QUS) measurements at the heel [broadband ultrasound attenuation (BUA)] in Caucasian women. We assessed NEAP and QUS in 401 very elderly Swiss ambulatory women. We evaluated dietary intake and NEAP estimates with a validated FFQ. QUS was measured using Achilles (Lunar). We identified 2 subgroups: 256 women (80.6 y +/- 3; BUA, 96.8 dB/MHz) with a fracture history and the remaining 145 (79.9 y SD 2.9; BUA, 101.7 dB/MHz) without. Women who reported having suffered a fracture had lower BUA (P < 0.001) than nonfractured women but did not differ in nutrient intakes and NEAP. Lower NEAP (P = 0.023) and higher potassium intake (P = 0.033) were correlated with higher BUA, which remained significant even after adjustment for age, BMI, and osteoporosis treatment. BUA was positively correlated with calcium (P = 0.016) and BMI (P < 0.001). Women who reported no fractures had no significant correlations between nutrient intake, NEAP, and BUA. Low nutritional acid load was correlated with higher BUA in very elderly women with a fracture history. Although relatively weak compared with age and BMI, this association was significant and may be an important additional risk factor that might be particularly relevant in frail patients with an already high fracture risk.