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The aim of the present study was to compare the effects of an α-linolenic acid-rich supplement (ALA-RS) on the ketogenic response and plasma long-chain ω-3 polyunsaturated fatty acid in healthy young adults and older individuals.Ten young (25 ± 0.9 y) and 10 older adults (73.1 ± 2.2 y) consumed a flaxseed oil supplement providing 2 g/d of ALA for 4 wk. Plasma ketones, nonesterified fatty acids (NEFA), triacylglycerols, glucose, and insulin were measured over 6 h, before and after supplementation. Total body fat mass was assessed before and after the ALA-RS.The ALA-RS did not significantly modify fasting ketones but postprandial production of β-hydroxybutyrate was increased by 26% (P = 0.037) only in the young adult group. Fasting plasma ketones were positively correlated to fasting plasma NEFA (P 0.01) in both groups. However, the relation was shifted to the right in the older group, suggesting that older adults needed higher plasma NEFA levels to achieve the same ketone amounts as young adults. At baseline, the older group had 47% higher total plasma fatty acids than the young group (P = 0.007). After the ALA-RS, plasma ALA doubled in both groups (P 0.01), an effect that was associated in the older group with a 40% higher eicosapentaenoic acid (EPA; P = 0.004), but no difference in docosahexaenoic acid. The postsupplementation increase in plasma ALA correlated positively with percent total body fat, especially in the older group (r(2) = 0.77; P = 0.0016).In young adults, ALA-RS mildly stimulated postprandial ketogenesis, whereas in the older group, it favored increased plasma ALA and EPA.

We are experiencing an epidemic of both diabetes and dementia among older adults in this country. The risk for dementia appears to be increased in patients with diabetes, and patients with dementia and diabetes appear to be at greater risk for severe hypoglycemia. In addition, there may be an increased risk for developing dementia by older patients with diabetes who have had episodes of severe hypoglycemia, although this issue is controversial. In this article, we review the factors that contribute to the increased risk for dementia in older adults with diabetes and outline the complex relationships between hypoglycemia and dementia.

Objectives Contribute evidence towards the complex interrelationships of body composition, physical performance and physical activity (PA) in an older population to assist in decisions for maintaining functional capacity in older adults. Design This is a cross-sectional analysis of an existing dataset in which a literature-supported model linking together the variables of interest is tested using path analysis. A proposed model with age, sex, energy intake and chronic diseases as predictors associated with body composition components, while the latter associated with physical performance and with PA acting both as a predictor and as an outcome of physical performance. Participants A sample of 847, community dwellers, non-diabetic older men and women from the Quebec Longitudinal Study on Nutrition and Successful Aging (NuAge Study). Measurements Physical performance tests were reduced to two indices: strength and mobility. Muscle mass index (MMI; kg/height 2 ) and % body fat were derived from DXA and bioimpedance analysis (BIA). PA was assessed by the Physical Activity Scale for the Elderly (PASE) and energy intakes were calculated from 24-hour food recalls. Data from the NuAge dataset served to test the relationships. The proposed model was evaluated using indices of fit. Results Significant associations were found for MMI and % body fat with mobility (β − 0.11 and − 0.02, respectively), and for MMI with strength (β = 0.60). PA was associated with MMI (β = 0.02) and negatively with % body fat (β = − 0.16), while mobility associated with PA (β = 0.65). Our hypothesized model, with some paths added, fit the data: chi-square = 4.64, root mean square error of approximation (RMSEA) = 0. Conclusions PA has desirable associations with body composition in older adults and mobility is associated with PA. These results stress the importance of taking into account the prior level of mobility when recommending PA for this age group. This model could explain in part the complex interrelationships that occur with aging and the potential factors that could be targeted to assist older individuals in maintaining functional capacity.

A cross-sectional study was designed to investigate the association between current consumption of a series of 26 common antioxidant-rich foods (ARF) with serum total antioxidant status (TAS) and plasma vitamin C and E levels in community-dwelling older adults. A convenience sample of the first 94 non-smoking Caucasian men (54%) and women (46%) enrolled in the Quebec Longitudinal Study NuAge were selected. The "Functional Foods Consumption Frequency Questionnaire" (FFCFQ) was administered at recruitment (T1) to ascertain patterns of consumption of ARF over the lifetime. The total Oxygen Radical Antioxidant Capacity (ORAC) of 25 ARF reported by subjects was estimated using published values. Serum TAS was determined based on the Trolox equivalent antioxidant capacity (TEAC) assay while plasma vitamins C and E (α- and γ-tocopherol) levels were analyzed by HPLC. The numbers of ARF eaten daily at T1, estimated from the FFCFQ and calculated from the diet recalls, were significantly correlated (r=0.51, P

Whether frail elderly subjects are more insulin resistant (IR) than non-frail is unclear. How obesity, muscle mass, inflammation, hormonal and lipid status, oxidative stress, antioxidant capacity and physical activity influences insulin sensitivity (IS) in frail elderly subjects remains uncertain. We determined (1) whether frail elderly persons are more IR than non-frail elderly and (2) the influence of abdominal fat mass (AFM), muscle mass index (MMI), inflammation (CRP), hormonal (cortisol, free IGF-1, DHEA) and lipid (FFA, triglyceride (TG)) status, oxidative stress (paraoxonase-1 (PON-1), malondialdehyde (MDA)), antioxidant capacity (vitamin C, E) and physical activity (PASE questionnaire) on IS (QUICKI) in 16 frail obese (FO), 17 frail lean (FL) and 21 healthy, non-obese (HN) elderly subjects. IS was lower in FO than FL, but there was no significant difference between HN and FO or FL. There were no significant differences among groups for CRP, cortisol, IGF-1, DHEA, FFA, TG, PON-1, MDA, vitamin C and E and PASE. Age, AFM and MMI significantly correlated with IS. Only AFM and MMI were significant predictors explaining, respectively, 18.5% and 8.5% of the variance in IS. Increased abdominal obesity is associated with IR in frail elderly. Non-obese frail persons are not more IR than their healthy counterparts.

The prevalence of type 2 diabetes increases with age. However, the management of diabetes in the elderly has received surprisingly little attention. Diabetes in the elderly is associated with a high risk of geriatric syndromes including malnutrition and sarcopenia, functional impairments, falls and fractures, incontinence, depression and dementia. Tight glycaemic control for the prevention of vascular complications is often of limited value in the elderly. However, glycaemic control and non-pharmacological therapy may prevent diabetes symptoms and delay geriatric syndromes. The prevention, screening and treatment of both conventional diabetic complications and geriatric syndromes should be integrated in a management plan to optimize the patients' overall health status and quality of life.

International audience; No-tillage is an increasing way of management for agricultural soils. The objective of this study was to identify in which extent the chemical properties of a loamy soil could be affected by no-tillage under temperate conditions. Soil chemical properties were investigated on a field subjected to either conventional or no-tillage management of maize (Zea mays L.) and wheat (Triticum aestivum L.) with identical fertilization practices and no lime supply since 1970. On no-tilled soil, maize was cropped exactly on the same line every other year, which enabled soil sampling under the row and under the interrow.Tilled soil had an homogeneous ploughed horizon, whereas soil under no-tillage exhibited strong vertical gradients of pH, exchangeable cations and organic C. No-tilled soil had 11.4% greater organic C than tilled soil, and the difference was concentrated in the upper 5 cm. The proportion of exchangeable cations was highest in the interrow of no-tilled soil and lowest in tilled soil. Tilled soil contained much lower exchangeable K than no-tilled soil, indicating a difference in retention capacity of this cation. The pH of the upper 5 cm of no-tilled soil was low, probably because of surface accumulation of organic residues. Whatever the tillage system, exchangeable Al was significantly related to pH according to the relation: Al-ex = 76441 x 10(-0.99) (pH) (r(2) = 0.96; p < 0.001). An expected complexing effect of organic matter on Al was not observed, probably hidden by the influence of pH. Since yields were not negatively affected by long-term no-tillage and organic C content was higher, no-tillage appears to be a cost-saving choice for maize and wheat production under these temperate environmental conditions, as well as a way for C sequestration. (c) 2006 Elsevier B.V. All rights reserved.

The effects of pravastatin (pravachol) compared with gemfibrozil on cholesterol-rich and trigylceride-rich lipoproteins were evaluated in this multi-centered trial. Following an 8-12 week prerandomization phase, 136 patients with NIDDM and hypercholesterolemia were randomized to receive either pravastatin 40 mg or gemfibrozil 1200 mg daily for 16 weeks. The reduction of total cholesterol (TC), betaquant LDL and LDL cholesterol (LDL-C) was significantly greater in patients treated with pravastatin than with gemfibrozil. However, gemofibrozil treatment resulted in a significantly greater reduction of triglyceride (TG) levels than did treatment with pravastatin. Pravastatin reduced the concentration of apoB (-19.3%, P0.001) and cholesterol-rich Lp-B (Lp-B+Lp-B; E) particles (-19%, P0.001) to a significantly greater extent (P-0.001) than gemfibrozil (-4.1 and -1%, respectively). Both gemfibrozil and pravastatin reduced the concentrations of trigylceride-rich Lp-Bc (-12.2 and -13.3%, respectively) and Lp-A-II;B;C;D;E (-19 and -12.7%, respectively) particles and their characteristic apoC-III constituent (-10.0 and -7.0%, respectively). In contrast, gemfibozil has a greater lowering effect compared with pravastatin on TG levels (-29.6 vs. -6.3%, respectively). Both pravastatin and gemfibrozil significantly increased the levels of apoA-I and, with both drugs, the elevated concentrations of apoA-I were due to significantly increased levels of Lp-A-I;A-II particles. By decreasing both cholesterol-rich Lp-B and triglyceride-rich Lp-Bc particles and increasing HDL-C and Lp-A-I;A-II particles in addition to proven efficacy in decreasing coronary events in NIDDM patients, pravastatin appears to be an appropriate choice for monotherapy in a broad range of diabetic patients with Type IIA and Type IIB hyperlipoproteinemias. These results also showed that direct measurement of lipoprotein family of particles provides important information not only about the composition but also the type and number of apoA- and apoB-containing lipoprotein particles.

The objective of this study was to determine the impact of an aerobic physical exercise program in the treatment of a group of elderly patients with type 2 diabetes mellitus (DM) in relation to metabolic control, physical capacity, quality of life (QOL) and attitudes toward diabetes. Patients were randomly assigned to either an experimental (n=19) or a control (n=20) group. The following measurements were conducted at baseline and after week 16: glycosylated hemoglobin (hbA1c), fructosamine, 3 h oral glucose tolerance test, treadmill test (Balke-Naughton), and a questionnaire on QOL and attitudes toward DM. After the intervention, the experimental group showed a significant decrease of glucose excursion during the oral glucose tolerance test (OGTT) (area under the curve) (16.6+/-3.8 vs. 15.3+/-3.1, P0.05) and an increase in total time on the treadmill (s) (423+/-207 vs. 471+/-230, P0.05). An improvement in the attitudes toward DM was observed in the experimental group (P=0.01) but not in the control group. Female gender, higher body mass index and hbA1c were factors associated with a response to the intervention. This study suggests that physical exercise has significant effects on glucose excursion during an OGTT and exercise tolerance in elderly patients with type 2 DM.

Plasma leptin has been shown to correlate positively with many indices of obesity, as well as insulin resistance. For a given body weight, the levels are higher in women than in men, but the reasons for this difference are not clear. Insulin has been shown to stimulate leptin production by adipose tissue in vivo and in vitro. Previous studies have reported that leptin levels are similar in diabetic and nondiabetic individuals. However, these studies were not performed in newly diagnosed diabetics, and other variables (such as gender) could have confounded the results. Therefore, the goal of the present cross-sectional study is to examine the effect of metabolic variables (such as glucose and insulin) on plasma leptin concentrations in men and women separately. We measured leptin levels in 48 subjects (17 with newly diagnosed type 2 diabetes mellitus, 13 with impaired glucose tolerance [IGT], and 18 normal individuals). The 3 groups were well matched for gender, age, and body mass index (BMI). When adjusted for the BMI and gender, a statistically significant gender-related difference in mean plasma leptin was observed across the 3 glucose tolerance subgroups (P < .03 by analysis of covariance [ANCOVA]). More specifically, plasma leptin levels were, on average, 44% lower in women with diabetes or IGT versus normal women (P < .02). No such between-group difference was observed in the men. In univariate analysis in the same female subgroup, plasma leptin correlated positively with fasting insulin (rs = +.43, P < .06) and negatively with 2-hour post-75-g glucose load plasma glucose concentration (rs = -.54, P < .02). In a multiple regression model controlling for the BMI in the female subgroup, circulating insulin and glucose concentrations 2 hours after the 75-g glucose load were good predictors of fasting plasma leptin (r = +.38, P = .02 and r = -.70, P < .001, respectively). Leptin levels in women appear to be influenced independently and to an important degree by ambient plasma glucose and plasma insulin concentrations. These findings suggest that the synthesis of leptin by adipose tissue is more susceptible to in vivo regulation by insulin and glucose in women than in men. Plasma leptin concentrations were also lower in women with IGT or type 2 diabetes versus normal women, suggesting that fasting and/or postprandial hyperglycemia interferes with the stimulatory effect of plasma insulin on the synthesis of leptin by adipose tissue in women only.

Experimental study of mechanical behaviour of clayey materials under hygrometric condition is usually performed either on unloaded samples or by means of classical oedometer tests used in soil mechanics. Such methods are not well adapted to hard deep clayey rocks with little deformability, porosity and permeability. Moreover, stress and strain tensors having a significant effect on hygro-mechanical behaviour and properties cannot be measured and investigated appropriately by classical tests. This is why a specific triaxial test was designed in which the sample is surrounded by a fiber glass tissue allowing air circulation and then by silicon on which confining pressure is applied. Thus, equilibrium between air and sample was reduced. Stress and strain tensors were also measured in time on the sample subjected to a mechanical loading and to a controlled suction. After presentation of the test, preliminary results are given.

The sulfonylurea gliclazide and the biguanide metformin have different mechanisms to reduce glycemia. We performed a randomized study to compare these two agents with respect to glycemic control and effects on lipid peroxidation markers in 36 adult patients with type 2 diabetes. Both agents significantly decreased glycosylated hemoglobin ([HbA1c] P < .05), fructosamine (P < .05), and the glucose-excursion curve during the oral glucose tolerance test ([OGTT] P < .01). With regard to the insulin curve during this test, no significant change was observed with metformin and a significant increase was measured with gliclazide (P < .05). Considering the small number of events, no significant difference was detected in the number of hypoglycemic episodes between the two agents. More upper-gastrointestinal (GI) symptoms were observed with metformin compared with gliclazide (P < .05). Even with no change in the standard lipid profile, both agents increased serum vitamin E (P < .01 for gliclazide and P < .05 for metformin) and decreased the level of lipid peroxidation markers in low-density lipoprotein (LDL) and high-density lipoprotein (HDL) particles (P < .05). Despite different mechanisms of action, gliclazide and metformin demonstrated comparable levels of efficacy and complementary effects on lipid peroxidation markers.

Fabric determination is fundamental to the understanding of several mechanims controlling a clayey soil behavior. Two techniques; namely, mercury intrusion tests and transmission electron microscopy (TEM) were used to study the soil fabric of a remoulded Boom clay. The effect of overburden pressure, excavation and desaturation on the soil fabric are studied. Results demonstrate that the nature of soil fabric is dependent on both the applied mechanical and hydraulic stress state conditions.