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Body composition assessment of undernourished older subjects by dual-energy x-ray absorptiometry and bioelectric impedance analysis

VILACA, K. H. C.; PAULA, F. J. A.; FERRIOLLI, E.; LIMA, N. K. C.; MARCHINI, J. S.; MORIGUTI, J. C.
Fonte: SPRINGER FRANCE Publicador: SPRINGER FRANCE
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
66.22%
The prevention and treatment of diseases related to changes in body composition require accurate methods for the measurement of body composition. However, few studies have dealt specifically with the assessment of body composition of undernourished older subjects by different methodologies. To assess the body composition of undernourished older subjects by two different methods, dual energy x-ray absorptiometry (DXA) and bioelectric impedance (BIA), and to compare results with those of an eutrophic group. The study model was cross-sectional; the study was performed at the University Hospital of the School of Medicine of Ribeiro Preto, University of So Paulo, Brazil. Forty-one male volunteers aged 62 to 91 years. The groups were selected on the basis of anamnesis, physical examination and nutritional assessment according to the Mini Nutritional Assessment (MNA) score. Body composition was assessed by DXA and BIA. Body weight, arm and calf circumference, body mass index (BMI), fat free mass (FFM) and fat mass (FM) were significantly lower in the undernourished group as compared to the eutrophic group. There were no significant differences between FFM and FM mean values determined by DXA and BIA in both groups, but the agreement between methods in the undernourished group was less strong. Our results suggest caution when BIA is to be applied in studies including undernourished older subjects. This study does not support BIA as an accurate method for the individual assessment of body composition.; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior - CAPES

Brain regions supporting verbal memory improvement in healthy older subjects

Miotto,Eliane C.; Balardin,Joana B.; Savage,Cary R.; Martin,Maria da Graça M.; Batistuzzo,Marcelo C.; Amaro Junior,Edson; Nitrini,Ricardo
Fonte: Academia Brasileira de Neurologia - ABNEURO Publicador: Academia Brasileira de Neurologia - ABNEURO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/09/2014 Português
Relevância na Pesquisa
66.17%
Despite growing interest in developing cognitive training interventions to minimize the aging cognitive decline process, no studies have attempted to explore which brain regions support the application of semantic strategies during verbal memory encoding. Our aim was to investigate the behavioral performance and brain correlates of these strategies in elderly individuals using fMRI in healthy older subjects. Method Subjects were scanned twice on the same day, before and after, directed instructions to apply semantic strategies during the encoding of word lists. Results Improved memory performance associated to increased semantic strategy application and brain activity in the left inferior and middle and right medial superior prefrontal cortex were found after the directed instructions. There was also reduced activation in areas related to strategy mobilization. Conclusion Improved memory performance in older subjects after the application of semantic strategies was associated with functional brain reorganization involving regions inside and outside the typical memory network.

Postprandial plasma retinyl ester response is greater in older subjects compared with younger subjects. Evidence for delayed plasma clearance of intestinal lipoproteins.

Krasinski, S D; Cohn, J S; Schaefer, E J; Russell, R M
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /03/1990 Português
Relevância na Pesquisa
46.19%
Postprandial vitamin A and intestinal lipoprotein metabolism was studied in 86 healthy men and women, aged 19-76 yr. Three independent experiments were carried out. In the first experiment, a supplement dose of vitamin A (3,000 retinol equivalents [RE]) was given without a meal to 59 subjects, aged 22-76 yr. In the second experiment, 20 RE/kg body wt was given with a fat-rich meal (1 g fat/kg body wt) to seven younger subjects (aged less than 50 yr) and seven older subjects (aged greater than or equal to 50 yr). In both experiments, postprandial plasma retinyl ester response increased significantly with advancing age (P less than 0.05). In the third experiment, retinyl ester-rich plasma was infused intravenously into nine young adult subjects (aged 18-30 yr) and nine elderly subjects (aged greater than or equal to 60 yr), and the rate of retinyl ester disappearance from plasma during the subsequent 3 h was determined. Mean (+/- SE) plasma retinyl ester residence time was 31 +/- 4 min in the young adult subjects vs. 57 +/- 8 min in the elderly subjects (P less than 0.05). These data are consistent with the concept that increased postprandial plasma retinyl ester concentrations in older subjects are due to delayed plasma clearance of retinyl esters in triglyceride-rich lipoproteins of intestinal origin.

Comparing performance on a simulated 12 hour shift rotation in young and older subjects

Reid, K; Dawson, D
Fonte: BMJ Group Publicador: BMJ Group
Tipo: Artigo de Revista Científica
Publicado em /01/2001 Português
Relevância na Pesquisa
46.34%
OBJECTIVES—To simulate a 12 hour shift rotation and measure the difference in performance if any, between older and younger subjects. Significant reductions in neurobehavioural performance during shift work and particularly night work have long been recognised. There are conflicting reports of the effects of 12 hour shifts on performance, alertness, and safety. Furthermore, research suggests that older shift workers have more sleep disruption and maladaption to shift work. When this is combined with longer hours at work there may be considerable reductions in performance for older compared with younger workers.
METHODS—Thirty two subjects were allocated to groups according to age. Group one had 16 subjects with a mean (SD) age of 21.2 (2.7) years, and group two had 16 subjects with a mean (SD) age of 43.9 (6.8) years. Subjects came to the laboratory for six consecutive days and completed a simulated 12 hour shift rotation consisting of two 12 hour day shifts (0700-1900), followed by two 12 hour night shifts (1900-0700). During the work period subjects completed a computer administered neurobehavioural performance task every hour.
RESULTS—Performance for the older subjects was consistently lower than for the younger subjects. There was a significant difference in performance across the shift between older and younger subjects. There was a significant change in performance across the shifts in the older subjects...

Comparison of Subjective and Objective Assessments of Sleep in Healthy Older Subjects Without Sleep Complaints

O’Donnell, Deirdre; Silva, Edward J.; Munch, Mirjam; Ronda, Joseph M.; Wang, Wei; Duffy, Jeanne F.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Publicado em /06/2009 Português
Relevância na Pesquisa
46.21%
Older adults have reduced sleep quality compared to younger adults when sleeping at habitual times, and greater sleep disruption when their sleep is at adverse times. The purpose of this analysis was to investigate how subjective measures of sleep relate to objectively-recorded sleep in older subjects scheduled to sleep at all times of day. We analyzed data from 24 healthy older (55–74 years) subjects who took part in a 32-day inpatient study where polysomnography (PSG) was recorded each night and subjective sleep was assessed after each scheduled wake time. The study included baseline nights and a forced desynchrony (FD) protocol when the subjects lived on a 20-hr rest-activity schedule. Our post-sleep questionnaire both included quantitative and qualitative questions about the prior sleep. Under baseline and FD conditions, objective and subjective sleep latency were correlated, subjective sleep duration was related to slow wave sleep and wake after sleep onset, subjective sleep quality was related to Stage 1 and 2 sleep, and sleepiness and refreshment at wake time were related to duration of premature awakening. During FD, most measures of objective and subjective sleep varied with circadian phase, and many additional correlations between objective and subjective sleep were present. Our findings show that when sleeping at habitual times...

Facilitating skilled right hand motor function in older subjects by anodal polarization over the left primary motor cortex

Hummel, Friedhelm C.; Heise, Kirstin; Celnik, Pablo; Floel, Agnes; Gerloff, Christian; Cohen, Leonardo G.
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.17%
Healthy aging is accompanied by limitations in performance of activities of daily living and personal independence. Recent reports demonstrated improvements in motor function induced by non-invasive anodal direct current stimulation (tDCS) of the primary motor cortex (M1) in young healthy adults. Here we tested the hypothesis that a single session of anodal tDCS over left M1 could facilitate performance of right upper extremity tasks required for activities of daily living (Jebsen-Taylor Hand function Test, JTT) in older subjects relative to sham in a double-blind crossover study design. We found (a) significant improvement in JTT function with tDCS relative to sham that outlasted the stimulation period by at least 30 minutes, (b) that the older the subjects the more prominent this improvement appeared and (c) that consistent with previous results in younger subjects, these effects were not accompanied by any overt undesired side effect. We conclude that anodal tDCS applied over M1 can facilitate performance of skilled hand functions required for activities of daily living in older subjects.

Altered negative priming in older subjects: first evidence from behavioral and neural level

Bauer, Eva; Gebhardt, Helge; Gruppe, Harald; Gallhofer, Bernd; Sammer, Gebhard
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Publicado em 01/10/2012 Português
Relevância na Pesquisa
46.14%
The impact of aging on the negative priming (NP) effect has been subject of many studies using behavioral measures. Results are inconsistent and corresponding neural data do not exist. We were interested in, whether or not processing of NP is altered in older in comparison to young adults (YA) on behavioral and neural level. Eighteen young and eighteen older healthy adults performed a location-based NP paradigm during fMRI. YA behaviorally showed a NP effect and NP associated fronto-striatal activation, which is in accordance with the inhibitory model of NP. In older subjects no significant behavioral NP effect and no NP-related activation in predefined brain regions could be found. This is discussed in context of the “loss of efficiency” hypothesis. One possible source for the lack of NP-related activation is a reduction of gray matter (GM) volume in older subjects as shown using voxel based morphometry (VBM).

Beneficial effect of a weight-stable, low-fat/low-saturated fat/low-glycaemic index diet to reduce liver fat in older subjects

Utzschneider, Kristina M.; Bayer-Carter, Jennifer L.; Arbuckle, Matthew D.; Tidwell, Jaime M.; Richards, Todd L.; Craft, Suzanne
Fonte: PubMed Publicador: PubMed
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.1%
Non-alcoholic fatty liver disease is associated with insulin resistance and dyslipidaemia and can progress to steatohepatitis and cirrhosis. We sought to determine whether dietary fat and saturated fat content alter liver fat in the absence of weight change in an older population. Liver fat was quantified by magnetic resonance spectroscopy before and after 4 weeks on an isoenergetic low-fat/low-saturated fat/low-glycaemic index (LGI) (LSAT: 23% fat/7% saturated fat/GI < 55) or a high-fat/high-saturated fat/high-GI (HSAT: 43% fat/24% saturated fat/GI > 70) diet in older subjects. In the present study, twenty subjects (seven males/thirteen females; age 69·3 (sem 1·6) years, BMI 26·9 (sem 0·8) kg/m2) were randomised to the LSAT diet and fifteen subjects (six males/nine females; age 68·6 (sem 1·8) years, BMI 28·1 (sem 0·9) kg/m2) to the HSAT diet. Weight remained stable. Liver fat decreased significantly on the LSAT diet (median 2·2 (interquartile range (IQR) 3·1) to 1·7 (IQR 1·8) %, P=0·002) but did not change on the HSAT diet (median 1·2 (IQR 4·1) to 1·6 (IQR 3·9) %). The LSAT diet lowered fasting glucose and total cholesterol, HDL-cholesterol and LDL-cholesterol and raised TAG (P<0·05), while the HSAT diet had no effect on glucose or HDL-cholesterol but increased total cholesterol and LDL-cholesterol (P<0·05). Fasting insulin and homeostasis model of insulin resistance did not change significantly on either diet...

Computer interaction : its effect on attitude and performance in older adults

Ansley, Jane
Fonte: FIU Digital Commons Publicador: FIU Digital Commons
Tipo: Artigo de Revista Científica Formato: application/pdf
Português
Relevância na Pesquisa
46.23%
This study examined the interaction of age, attitude, and performance within the context of an interactive computer testing experience. Subjects were 13 males and 47 females between the ages of 55 and 82, with a minimum of a high school education. Initial attitudes toward computers, as measured by the Cybernetics Attitude Scale (CAS), demonstrated overall equivalence between these older subjects and previously tested younger subjects. Post-intervention scores on the CAS indicated that attitudes toward computers were unaffected by either a "fun" or a "challenging" computer interaction experience. The differential effects of a computerized vs. a paperand- pencil presentation format of a 20-item, multiple choice vocabulary test were examined. Results indicated no significant differences in the performance of subjects in the two conditions, and no interaction effect between attitude and performance. These findings suggest that the attitudes of older adults towards computers do not affect their computerized testing performance, at least for short term testing of verbal abilities. A further implication is that, under the conditions presented here, older subjects appear to be unaffected by mode of testing. The impact of recent advanced in technology on older adults is discussed.

Energy intake and appetite are related to antral area in healthy young and older subjects

Sturm, K.; Parker, B.; Wishart, J.; Feinle-Bisset, C.; Jones, K.; Chapman, I.; Horowitz, M.
Fonte: Amer Soc Clinical Nutrition Publicador: Amer Soc Clinical Nutrition
Tipo: Artigo de Revista Científica
Publicado em //2004 Português
Relevância na Pesquisa
66.33%
BACKGROUND: Gastric distension reduces food intake, and antral, rather than proximal, gastric distension may be the dominant mechanism in the induction of appetite-related sensations. Healthy aging is associated with reduced appetite. OBJECTIVE: We examined the effects of different energy preloads on appetite, plasma cholecystokinin, antral area, and subsequent energy intake in healthy older and young subjects. DESIGN: On 3 separate days, 12 young and 12 older subjects consumed 400 mL of a drink containing either 0 kcal (water), 250 kcal, or 750 kcal 70 min before a buffet-style meal. RESULTS: Hunger was less in the older than in the young subjects (P < 0.001). Both nutrient preloads reduced hunger and increased fullness more than did water (P < 0.02), and older subjects were more full than were the young (P < 0.05). Antral area was greater after the nutrient preloads than after water (P = 0.001) and greater in the older than in the young subjects (P = 0.005). In both groups, food intake was suppressed in an energy-dependent manner (P = 0.008). Plasma cholecystokinin was greater in the older than in the young subjects (P = 0.003). Immediately before the meal, hunger (r = -0.59) and energy intake (r = -0.90) were inversely related and fullness (r = 0.66) was directly related to antral area (all: P < 0.001). Antral area...

Role of nitric oxide mechanisms in gastric emptying of, and the blood pressure and glycemic responses to, oral glucose in healthy older subjects

Gentilcore, D.; Visvanathan, R.; Russo, A.; Chaikomin, R.; Stevens, J.; Wishart, J.; Tonkin, A.; Horowitz, M.; Jones, K.
Fonte: Amer Physiological Soc Publicador: Amer Physiological Soc
Tipo: Artigo de Revista Científica
Publicado em //2005 Português
Relevância na Pesquisa
46.15%
The primary aims of this study were to evaluate the effects of the nitric oxide (NO) synthase inhibitor NG-nitro-L-arginine methyl ester (L-NAME) on gastric emptying (GE) of, and the blood pressure (BP), glycemic, insulin, and incretin responses to, oral glucose in older subjects. Eight healthy subjects (4 males and 4 females, aged 70.9 ± 1.3 yr) were studied on two separate days, in double-blind, randomized order. Subjects received an intravenous infusion of either L-NAME (180 µg·kg–1·h–1) or saline (0.9%) at a rate of 3 ml/min for 150 min. Thirty minutes after the commencement of the infusion (0 min), subjects consumed a 300-ml drink containing 50 g glucose labeled with 20 MBq 99mTc-sulfur colloid, while sitting in front of a gamma camera. GE, BP (systolic and diastolic), heart rate (HR), blood glucose, plasma insulin, and incretin hormones, glucose-dependant insulinotropic-polypeptide (GIP), and glucagon-like peptide-1 (GLP-1), were measured. L-NAME had no effect on GE, GIP, and GLP-1. Between –30 and 0 min L-NAME had no effect on BP or HR. After the drink (0–60 min), systolic and diastolic BP fell (P < 0.05) and HR increased (P < 0.01) during saline; these effects were attenuated (P < 0.001) by L-NAME. Blood glucose levels between 90 and 150 min were higher (P < 0.001) and plasma insulin were between 15 and 150 min less (P < 0.001) after L-NAME. The fall in BP...

Role of 5-hydroxytryptamine mechanisms in mediating the effects of small intestinal glucose on blood pressure and antropyloroduodenal motility in older subjects

Gentilcore, D.; Little, T.; Feinle-Bisset, C.; Samsom, M.; Smout, A.; Horowitz, M.; Jones, K.
Fonte: Amer Physiological Soc Publicador: Amer Physiological Soc
Tipo: Artigo de Revista Científica
Publicado em //2007 Português
Relevância na Pesquisa
46.1%
Postprandial hypotension is an important clinical problem, particularly in the elderly. 5-Hydroxytryptamine3 (5-HT3) mechanisms may be important in the regulation of splanchnic blood flow and blood pressure (BP), and in mediating the effects of small intestinal nutrients on gastrointestinal motility. The aims of this study were to evaluate the effects of the 5-HT3 antagonist granisetron on the BP, heart rate (HR), and antropyloroduodenal (APD) motility responses to intraduodenal glucose in healthy older subjects. Ten subjects (5 male, 5 female, aged 65-76 yr) received an intraduodenal glucose infusion (3 kcal/min) for 60 min (t = 0-60 min), followed by intraduodenal saline for a further 60 min (t = 60-120 min) on 2 days. Granisetron (10 microg/kg) or control (saline) was given intravenously at t = -25 min. BP (systolic and diastolic), HR, and APD pressures were measured. Pressure waves in the duodenal channel closest ("local") to the infusion site were quantified separately. During intraduodenal glucose, there were falls in systolic and diastolic BP and a rise in HR (P < 0.0001 for all); granisetron had no effect on these responses. Granisetron suppressed the number and amplitude (P < 0.05 for both) of local duodenal pressures during intraduodenal glucose. Otherwise...

The effect of intraduodenal glucose on muscle sympathetic nerve activity in healthy young and older subjects

Van Orshoven, N.; Van Schelven, L.; Akkermans, L.; Jansen, P.; Horowitz, M.; Feinle-Bisset, C.; Van Huffelen, A.; Oey, P.
Fonte: Dr Dietrich Steinkopf Verlag Publicador: Dr Dietrich Steinkopf Verlag
Tipo: Artigo de Revista Científica
Publicado em //2008 Português
Relevância na Pesquisa
46.16%
Objective The cardiovascular response to a meal is modulated by gastric distension and the interaction of nutrients, particularly carbohydrate, within the small intestine. We tested the hypothesis that the depressor effect of small intestinal glucose is greater in older than in young subjects, because the reflex increase in muscle sympathetic nerve activity (MSNA) is blunted by age. Methods The effects of intraduodenal glucose infusion (IDGI) on blood pressure, heart rate and MSNA were evaluated in eight healthy young subjects (4 women; mean age ± SEM: 28.8 ± 3.4 years), eight healthy elderly (4 women; 75.3 ± 1.6 years) and in two patients with symptomatic postprandial hypotension (PPH), one young (21 years), and one old (90 years). Results In both young and elderly healthy subjects, IDGI decreased blood pressure (P < 0.05), but the fall in systolic blood pressure was greater in the older subjects (−17.0 ± 4.1 vs. −6.5 ± 1.6 mmHg, P < 0.03). MSNA increased similarly, after infusion in both young (9.0 ± 3.4 bursts/min) and elderly (7.8 ± 1.0 bursts/min) subjects. Baroreflex sensitivity for number of sympathetic bursts was attenuated in the elderly (P < 0.03). The increase in burst area in the young patient with PPH was attenuated (18 vs. 63% in the healthy young group). Interpretation The fall in BP induced by IDGI was greater in healthy elderly compared to healthy young subjects. The reason for this is unclear...

Comparative effects of glucose and xylose on blood pressure, gastric emptying and incretin hormones in healthy older subjects

Vanis, L.; Hausken, T.; Gentilcore, D.; Rigda, R.; Rayner, C.; Feinle-Bisset, C.; Horowitz, M.; Jones, K.
Fonte: C A B I Publishing Publicador: C A B I Publishing
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
46.22%
Postprandial hypotension is an important disorder for which current management is suboptimal. In healthy older subjects, oral and small-intestinal glucose administration decreases blood pressure (BP), and the magnitude of the reduction is dependent on the rate of glucose entry into the small intestine and, possibly, the release of glucagon-like peptide-1 (GLP-1). There is little information about the effects of other carbohydrates, particularly those poorly absorbed, on BP. The aim of the present study was to compare the effects of drinks containing xylose, glucose or water alone on BP, gastric emptying (GE), incretin hormone secretion, glycaemia and insulinaemia in healthy older subjects. A total of eight healthy older subjects (aged 65–75 years) had simultaneous measurements of BP (DINAMAP), GE (three-dimensional ultrasound), blood glucose, serum insulin, GLP-1 and glucose-dependent insulinotropic peptide (GIP), on three separate occasions, in a double-blind, randomised order. On each day, subjects consumed a 300 ml drink of water, glucose (50 g) or d-xylose (50 g). Glucose (P = 0·02), but not xylose (P = 0·63), was associated with a fall in BP. There was no difference in the GE of glucose and xylose (P = 0·47); both emptied slower than water (P < 0·001). Xylose had minimal effects on blood glucose...

Effects of small intestinal glucose load on blood pressure, splanchnic blood flow, glycaemia and GLP-1 release in healthy older subjects

Vanis, L.; Gentilcore, D.; Rayner, C.; Wishart, J.; Horowitz, M.; Feinle-Bisset, C.; Jones, K.
Fonte: Amer Physiological Soc Publicador: Amer Physiological Soc
Tipo: Artigo de Revista Científica
Publicado em //2011 Português
Relevância na Pesquisa
46.13%
Postprandial hypotension is an important problem, particularly in the elderly. The fall in blood pressure is dependent on small intestinal glucose delivery and, possibly, changes in splanchnic blood flow, the release of glucagon-like peptide-1 (GLP-1), and sympathetic nerve activity. We aimed to determine in healthy older subjects, the effects of variations in small intestinal glucose load on blood pressure, superior mesenteric artery flow, GLP-1, and noradrenaline. Twelve subjects (6 male, 6 female; ages 65–76 yr) were studied on four separate occasions, in double-blind, randomized order. On each day, subjects were intubated via an anesthetized nostril, with a nasoduodenal catheter, and received an intraduodenal infusion of either saline (0.9%) or glucose at a rate of 1, 2, or 3 kcal/min (G1, G2, G3, respectively), for 60 min (t = 0–60 min). Between t = 0 and 60 min, there were falls in systolic and diastolic blood pressure following G2 and G3 (P = 0.003 and P < 0.001, respectively), but no change during saline or G1. Superior mesenteric artery flow increased slightly during G1 (P = 0.01) and substantially during G2 (P < 0.001) and G3 (P < 0.001), but not during saline. The GLP-1 response to G3 was much greater (P < 0.001) than to G2 and G1. Noradrenaline increased (P < 0.05) only during G3. In conclusion...

Effects of variations in intragastric volume on blood pressure and splanchnic blood flow during intraduodenal glucose infusion in healthy older subjects

Vanis, L.; Gentilcore, D.; Lange, K.; Gilja, O.; Rigda, R.; Trahair, L.; Feinle-Bisset, C.; Rayner, C.; Horowitz, M.; Jones, K.
Fonte: Amer Physiological Soc Publicador: Amer Physiological Soc
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
Relevância na Pesquisa
46.13%
The postprandial reduction in blood pressure (BP) is triggered by the interaction of nutrients with the small intestine and associated with an increase in splanchnic blood flow. Gastric distension may attenuate the postprandial fall in BP. The aim of this study was to determine the effects of differences in intragastric volume, including distension at a low (100 ml) volume, on BP and superior mesenteric artery (SMA) blood flow responses to intraduodenal glucose in healthy older subjects. BP and heart rate (HR; automated device), SMA blood flow (Doppler ultrasound), mesenteric vascular resistance (MVR), and plasma norepinephrine of nine male subjects (65–75 yr old) were measured after an overnight fast on 4 separate days in random order. On each day, subjects were intubated with a nasoduodenal catheter, incorporating a duodenal infusion port, and orally with a second catheter, incorporating a barostat bag, positioned in the fundus. Each subject received a 60-min (t = 0–60 min) intraduodenal glucose infusion (3 kcal/min) and gastric distension at a volume of 1) 0 ml (V0), 2) 100 ml (V100), 3) 300 ml (V300), or 4) 500 ml (V500). Systolic BP fell (P < 0.05) during V0, but not during V100, V300, or V500. In contrast, HR (P < 0.01) and SMA blood flow (P < 0.001) increased and MVR decreased (P < 0.05) comparably on all 4 days. Plasma norepinephrine rose (P < 0.01) in response to intraduodenal glucose...

Comparative effects of variations in duodenal glucose load on glycemic, insulinemic, and incretin responses in healthy young and older subjects

Trahair, L.; Horowitz, M.; Rayner, C.; Gentilcore, D.; Lange, K.; Wishart, J.; Jones, K.
Fonte: Endocrine Society Publicador: Endocrine Society
Tipo: Artigo de Revista Científica
Publicado em //2012 Português
Relevância na Pesquisa
46.28%
CONTEXT: Aging is associated with deteriorating glucose tolerance. Studies assessing glucose tolerance and subsequent insulin and incretin hormone release often fail to take into account the rate of gastric emptying when evaluating these responses. OBJECTIVE: Our objective was to determine the comparative effects of variations in the small intestinal glucose load on the glycemic, insulinemic, and incretin responses in healthy young and older subjects. MATERIALS AND METHODS: Twelve healthy young (six males, six females; age 22.2±2.3 yr) and 12 older (six males, six females; age 68.7±1.0 yr) subjects had measurements of blood glucose, serum insulin and plasma incretin hormones [glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic polypeptide (GIP)] and calculations of insulin resistance (homeostatic model assessment) and β-cell function corrected for insulin sensitivity, before and during intraduodenal infusions of glucose at 1, 2, or 3 kcal/min or saline for 60 minutes. The study was double-blinded and randomized, and performed in the Discipline of Medicine at the Royal Adelaide Hospital. RESULTS: At baseline, blood glucose and serum insulin were slightly higher in the older subjects (P<0.001), whereas GLP-1 and GIP were comparable between groups. In both groups...

Impact of gastric emptying to the glycemic and insulinemic responses to a 75-g oral glucose load in older subjects with normal and impaired glucose tolerance

Trahair, L.G.; Horowitz, M.; Marathe, C.S.; Lange, K.; Standfield, S.; Rayner, C.K.; Jones, K.L.
Fonte: Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society. Publicador: Wiley Periodicals, Inc. on behalf of the American Physiological Society and The Physiological Society.
Tipo: Artigo de Revista Científica
Publicado em //2014 Português
Relevância na Pesquisa
66.15%
The majority of studies relating to the oral glucose tolerance test (OGTT) have not taken gastric emptying (GE), which exhibits a substantial inter-individual variation, into account. We sought to evaluate the impact of GE, on the glycemic and insulinemic responses to a 75-g oral glucose load in older subjects with normal and impaired glucose tolerance. Eighty-seven healthy 'older' subjects (47F, 40M; age 71.0 ± 0.5 year) were given a drink comprising of 75-g glucose and 150 mg C(13)-acetate made up to 300 mL with water on a single occasion. Exhaled breath was obtained for analysis of (13)CO2 and calculation of the 50% GE time (T50). Blood glucose, serum insulin and plasma glucagon-like peptide-1 (GLP-1) and glucose-dependent insulinotropic peptide (GIP) were measured, and the insulin sensitivity index (ISI), and the disposition index (DI), were calculated. Thirty-one subjects had normal glucose tolerance (NGT) and 46 had impaired glucose tolerance (IGT). Blood glucose at t = 60 min and t = 120 min were related inversely to ISI (P < 0.001) and DI P < 0.001). The rise in blood glucose at t = 60 min was related inversely to the T50 in all subjects (P < 0.01), and those with IGT (P < 0.001), but not NGT. There were no significant relationships between the blood glucose at t = 120 min with the T50...

Prevalencia de las deficiencias de zinc y cobre en adultos mayores de la Región Metropolitana de Santiago; Prevalence of zinc and copper deficiencies in older subjects living in Metropolitan Santiago

Araya, Magdalena; Albala Brevis, Cecilia Hortensia; Lera, Lydia; Pizarro, Fernando; Olivares, Manuel
Fonte: SOC MEDICA SANTIAGO Publicador: SOC MEDICA SANTIAGO
Tipo: Artículo de revista
Português
Relevância na Pesquisa
46.17%
Artículo de publicación ISI; Background: Older subjects have a high risk of developing zinc and copper deficiencies. Aim: To determine the prevalence of copper and zinc deficiencies in adults aged over 60 years, living in Metropolitan Santiago. Subjects and Methods: Analyses were performed using anonymous serum samples from older subjects living in Santiago, Chile, who participated in the multicenter project SABE. Of the studied subjects, 49.3% had enough left-over serum to measure serum zinc and copper concentrations by atomic absorption spectrometry. Results: A total of 444 men and 198 women were studied. A positive correlation between serum zinc and copper was found in both women (r = 0.44, p < 0.001) and men (r = 0.48, p < 0.001). There were no differences in serum zinc concentration by sex and age. The prevalence of subnormal serum zinc values was 66.9% in women and 66.7% in men. Women had a significantly higher serum copper values than men (p < 0.02) and there were no differences by age. Prevalence of subnormal serum copper values was higher in women than in men (32.9 and 23.7% respectively, p < 0.05). Women had significantly higher copper/zinc serum ratio than men (p < 0.001). Conclusions: Older people living in Metropolitan Santiago have a high prevalence of copper and zinc deficiencies.

Strategies used during a challenging weighted walking task in healthy, older adults and subjects with knee osteoarthritis

Kubinski, Andrew
Fonte: University of Delaware Publicador: University of Delaware
Tipo: Tese de Doutorado
Português
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Higginson, Jill S.; Knee osteoarthritis (OA) is a degenerative joint disease that affects millions of people. While numerous gait differences have been identified between healthy adults and adults with knee OA and some studies have looked at how biomechanics differ during challenging conditions, none have studied healthy, older adults or adults with knee OA during a challenging weighted walking task. Because loading is important to the initiation and progression of knee OA and this type of challenging task will increase the forces that must be absorbed by the body, we investigated the effect of weighted walking on initial contact and loading response (weight acceptance task). We used a split belt instrumented treadmill and motion capture technology to analyze the gait of 40 subjects (20 healthy and 20 knee OA) walking at 1.0 meter per second while unweighted and weighted with 1/6th of their body weight in a front and back loaded weight vest. Subjects were grouped according to their Kellgren and Lawrence (K/L) radiographic score. Healthy subjects had a K/L ≤ 1, while knee OA subjects had a K/L ≥ 2. The analysis of initial contact focused on the position of the ankle, knee, and hip in the sagittal plane and step length. The analysis of the loading response included double support percent...