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Sample records for caloric restriction shortens

  1. Maternal caloric restriction prior to pregnancy increases the body weight of the second-generation male offspring and shortens their longevity in rats.

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    Araminaite, Violeta; Zalgeviciene, Violeta; Simkunaite-Rizgeliene, Renata; Stukas, Rimantas; Kaminskas, Arvydas; Tutkuviene, Janina

    2014-01-01

    Maternal undernutrition can affect offspring's physical status and various health parameters that might be transmittable across several generations. Many studies have focused on undernutrition throughout pregnancy, whereas maternal undernutrition prior to pregnancy is not sufficiently studied. The objective of our study was to explore the effects of food restriction prior to and during pregnancy on body weight and longevity of the second generation offspring. Adult female Wistar rats ("F0" generation) were 50% food restricted for one month prior to pregnancy (pre-pregnancy) or during pre-pregnancy and pregnancy. The third group was fed normally (control). The first generation offspring were normally fed until the 6(th) month of age to produce the second generation offspring; namely, the first-generation female rats were mated with male breeders from outside the experiment. The second generation offspring thus obtained were observed until natural death (up to 36 months). Compared to the controls, the second-generation male offspring whose "grandmothers (F0 females)" undernourished only during pre-pregnancy were significantly heavier from the 8(th) month of age, whereas no significant weight difference was found in the male offspring whose "grandmothers" were food-restricted during pre-pregnancy and pregnancy. Shorter lifespan was observed in the second-generation male offspring of "grandmothers" that were food-restricted either during pre-pregnancy or during pre-pregnancy and pregnancy. By contrast, no differences in body weight and lifespan were observed in all second-generation female offspring. In conclusion, maternal caloric restriction prior to pregnancy increases the body weight and shortens the longevity of the second-generation male offspring, indicating the sex-dependent transgenerational effect of maternal caloric restriction.

  2. Epigenetic regulation of caloric restriction in aging

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    Daniel Michael

    2011-08-01

    Full Text Available Abstract The molecular mechanisms of aging are the subject of much research and have facilitated potential interventions to delay aging and aging-related degenerative diseases in humans. The aging process is frequently affected by environmental factors, and caloric restriction is by far the most effective and established environmental manipulation for extending lifespan in various animal models. However, the precise mechanisms by which caloric restriction affects lifespan are still not clear. Epigenetic mechanisms have recently been recognized as major contributors to nutrition-related longevity and aging control. Two primary epigenetic codes, DNA methylation and histone modification, are believed to dynamically influence chromatin structure, resulting in expression changes of relevant genes. In this review, we assess the current advances in epigenetic regulation in response to caloric restriction and how this affects cellular senescence, aging and potential extension of a healthy lifespan in humans. Enhanced understanding of the important role of epigenetics in the control of the aging process through caloric restriction may lead to clinical advances in the prevention and therapy of human aging-associated diseases.

  3. Dietary restriction with and without caloric restriction for healthy aging [version 1; referees: 3 approved

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    Changhan Lee

    2016-01-01

    Full Text Available Caloric restriction is the most effective and reproducible dietary intervention known to regulate aging and increase the healthy lifespan in various model organisms, ranging from the unicellular yeast to worms, flies, rodents, and primates. However, caloric restriction, which in most cases entails a 20–40% reduction of food consumption relative to normal intake, is a severe intervention that results in both beneficial and detrimental effects. Specific types of chronic, intermittent, or periodic dietary restrictions without chronic caloric restriction have instead the potential to provide a significant healthspan increase while minimizing adverse effects. Improved periodic or targeted dietary restriction regimens that uncouple the challenge of food deprivation from the beneficial effects will allow a safe intervention feasible for a major portion of the population. Here we focus on healthspan interventions that are not chronic or do not require calorie restriction.

  4. Lifelong caloric restriction increases working memory in mice.

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    Angela Kuhla

    Full Text Available Caloric restriction (CR is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  5. Lifelong caloric restriction increases working memory in mice.

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    Kuhla, Angela; Lange, Sophie; Holzmann, Carsten; Maass, Fabian; Petersen, Jana; Vollmar, Brigitte; Wree, Andreas

    2013-01-01

    Caloric restriction (CR) is argued to positively affect general health, longevity and the normally occurring age-related reduction of cognition. This issue is well examined, but most studies investigated the effect of short-term periods of CR. Herein, 4 weeks old female mice were fed caloric restricted for 4, 20 and especially for 74 weeks. CR mice received 60% of food eaten by their ad libitum (AL) fed littermates, and all age-matched groups were behaviorally analyzed. The motor coordination, which was tested by rotarod/accelerod, decreased age-related, but was not influenced by the different periods of CR. In contrast, the age-related impairment of spontaneous locomotor activity and anxiety, both being evaluated by open field and by elevated plus maze test, was found aggravated by a lifelong CR. Measurement of cognitive performance with morris water maze showed that the working memory decreased age-related in AL mice, while a lifelong CR caused a better cognitive performance and resulted in a significantly better spatial memory upon 74 weeks CR feeding. However, a late-onset CR feeding in 66 weeks old mice did not ameliorate the working memory. Therefore, a lifelong CR seems to be necessary to improve working memory.

  6. Perspective food addiction, caloric restriction, and dopaminergic neurotransmission

    DEFF Research Database (Denmark)

    Stankowska, Arwen Urrsula Malgorzata; Gjedde, Albert

    2013-01-01

    , and reduced activity in prefrontal regions of the cerebral cortex. The neurobiological characteristics suggest that obese people also have a pathological dependence in common with addicts, in the form of food addiction. Malnutrition and dieting both relate to binge eating, possibly as a compensation...... for a reduced cognitive reward condition. The combination of caloric restriction and food addiction imparts a high risk of relapse as a result of further reduction of dopaminergic neurotransmission and the subsequent loss of reward. As with drugs of abuse, ingestion of large quantities of sugar in circumstances...... of uncontrolled eating increases dopamine release in the nucleus accumbens. This and other evidence suggests that abuse of food is a habit learned by means of mechanisms centred in the basal ganglia, with an increased risk of relapse in the presence of associative amplifiers. This risk is predicted...

  7. Caloric Restriction in Lean and Obese Strains of Laboratory ...

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    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improved longevity with caloric restriction (CR) in rodents. Little is known regarding effects of CR in genetically lean versus obese strains. Long-Evans (LE) and Brown Norway (BN) rats make an ideal comparison for a CR study because the percentage body fat of young adult LE rats is double that of BN rats. Male LE and BN rats were either fed ad libitum (AL) or were caloricallyrestricted to 80 or 90% of their AL weight. The percentages of fat, lean and fluid mass were measured non-invasively at 2- to 4-week intervals. Metabolic rate and respiratory quotient were measured after 3, 6, 9 and 12 months of CR. Overall health was scored monthly. The percentage of fat of the LE strain decreased with CR, whereas the percentage of fat of the BN strain remained above the AL group for several months. The percentage of lean mass increased above the AL for both strains subjected to CR. The percentage offluid was unaffected by CR. The average metabolic rate over 22 h of the BN rats subjected to CR was reduced, whereas that of LE rats was increased slightly above the AL group. The respiratory quotient of BN rats wasdecreased with CR. Overall health of the CR LE group was significantly improved compared with t

  8. Fasting and Caloric Restriction in Cancer Prevention and Treatment.

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    Brandhorst, Sebastian; Longo, Valter D

    Cancer is the second leading cause of death in the USA and among the leading major diseases in the world. It is anticipated to continue to increase because of the growth of the aging population and prevalence of risk factors such as obesity, smoking, and/or poor dietary habits. Cancer treatment has remained relatively similar during the past 30 years with chemotherapy and/or radiotherapy in combination with surgery remaining the standard therapies although novel therapies are slowly replacing or complementing the standard ones. According to the American Cancer Society, the dietary recommendation for cancer patients receiving chemotherapy is to increase calorie and protein intake. In addition, there are no clear guidelines on the type of nutrition that could have a major impact on cancer incidence. Yet, various forms of reduced caloric intake such as calorie restriction (CR) or fasting demonstrate a wide range of beneficial effects able to help prevent malignancies and increase the efficacy of cancer therapies. Whereas chronic CR provides both beneficial and detrimental effects as well as major compliance challenges, periodic fasting (PF), fasting-mimicking diets (FMDs), and dietary restriction (DR) without a reduction in calories are emerging as interventions with the potential to be widely used to prevent and treat cancer. Here, we review preclinical and preliminary clinical studies on dietary restriction and fasting and their role in inducing cellular protection and chemotherapy resistance.

  9. Repletion of TNFα or leptin in calorically restricted mice suppresses post-restriction hyperphagia

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    Hambly, Catherine; Duncan, Jacqueline S.; Archer, Zoë A.; Moar, Kim M.; Mercer, Julian G.; Speakman, John R.

    2012-01-01

    SUMMARY The causes of post-restriction hyperphagia (PRH) represent a target for drug-based therapies to prevent obesity. However, the factors causing PRH are poorly understood. We show that, in mice, the extent of PRH was independent of the time under restriction, but depended on its severity, suggesting that PRH was driven by signals from altered body composition. Signals related to fat mass were important drivers. Circulating levels of leptin and TNFα were significantly depleted following caloric restriction (CR). We experimentally repleted their levels to match those of controls, and found that in both treatment groups the level of PRH was significantly blunted. These data establish a role for TNFα and leptin in the non-pathological regulation of energy homeostasis. Signals from adipose tissue, including but not limited to leptin and TNFα, regulate PRH and might be targets for therapies that support people engaged in CR to reduce obesity. PMID:21954068

  10. Cardioprotective Signature of Short-Term Caloric Restriction.

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    Hossein Noyan

    Full Text Available To understand the molecular pathways underlying the cardiac preconditioning effect of short-term caloric restriction (CR.Lifelong CR has been suggested to reduce the incidence of cardiovascular disease through a variety of mechanisms. However, prolonged adherence to a CR life-style is difficult. Here we reveal the pathways that are modulated by short-term CR, which are associated with protection of the mouse heart from ischemia.Male 10-12 wk old C57bl/6 mice were randomly assigned to an ad libitum (AL diet with free access to regular chow, or CR, receiving 30% less food for 7 days (d, prior to myocardial infarction (MI via permanent coronary ligation. At d8, the left ventricles (LV of AL and CR mice were collected for Western blot, mRNA and microRNA (miR analyses to identify cardioprotective gene expression signatures. In separate groups, infarct size, cardiac hemodynamics and protein abundance of caspase 3 was measured at d2 post-MI.This short-term model of CR was associated with cardio-protection, as evidenced by decreased infarct size (18.5±2.4% vs. 26.6±1.7%, N=10/group; P=0.01. mRNA and miR profiles pre-MI (N=5/group identified genes modulated by short-term CR to be associated with circadian clock, oxidative stress, immune function, apoptosis, metabolism, angiogenesis, cytoskeleton and extracellular matrix (ECM. Western blots pre-MI revealed CR-associated increases in phosphorylated Akt and GSK3ß, reduced levels of phosphorylated AMPK and mitochondrial related proteins PGC-1α, cytochrome C and cyclooxygenase (COX IV, with no differences in the levels of phosphorylated eNOS or MAPK (ERK1/2; p38. CR regimen was also associated with reduced protein abundance of cleaved caspase 3 in the infarcted heart and improved cardiac function.

  11. Caloric restriction decreases orthostatic tolerance independently from 6° head-down bedrest.

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    John P Florian

    Full Text Available Astronauts consume fewer calories during spaceflight and return to earth with an increased risk of orthostatic intolerance. Whether a caloric deficiency modifies orthostatic responses is not understood. Thus, we determined the effects of a hypocaloric diet (25% caloric restriction during 6° head down bedrest (an analog of spaceflight on autonomic neural control during lower body negative pressure (LBNP. Nine healthy young men completed a randomized crossover bedrest study, consisting of four (2 weeks each interventions (normocaloric bedrest, normocaloric ambulatory, hypocaloric bedrest, hypocaloric ambulatory, each separated by 5 months. Muscle sympathetic nerve activity (MSNA was recorded at baseline following normocaloric and hypocaloric interventions. Heart rate (HR and arterial pressure were recorded before, during, and after 3 consecutive stages (7 min each of LBNP (-15, -30, -45 mmHg. Caloric and posture effects during LBNP were compared using two-way ANOVA with repeated measures. There was a strong trend toward reduced basal MSNA following caloric restriction alone (normcaloric vs. hypocaloric: 22±3 vs. 14±4 burst/min, p = 0.06. Compared to the normocaloric ambulatory, both bedrest and caloric restriction were associated with lower systolic blood pressure during LBNP (p<0.01; however, HR responses were directionally opposite (i.e., increase with bedrest, decrease with caloric restriction. Survival analysis revealed a significant reduction in orthostatic tolerance following caloric restriction (normocaloric finishers: 12/16; hypocaloric finishers: 6/16; χ2, p = 0.03. Caloric restriction modifies autonomic responses to LBNP, which may decrease orthostatic tolerance after spaceflight.

  12. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    OpenAIRE

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were ...

  13. Effects of Caloric Restriction on Cardiac Oxidative Stress and Mitochondrial Bioenergetics: Potential Role of Cardiac Sirtuins

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    Ken Shinmura

    2013-01-01

    Full Text Available The biology of aging has not been fully clarified, but the free radical theory of aging is one of the strongest aging theories proposed to date. The free radical theory has been expanded to the oxidative stress theory, in which mitochondria play a central role in the development of the aging process because of their critical roles in bioenergetics, oxidant production, and regulation of cell death. A decline in cardiac mitochondrial function associated with the accumulation of oxidative damage might be responsible, at least in part, for the decline in cardiac performance with age. In contrast, lifelong caloric restriction can attenuate functional decline with age, delay the onset of morbidity, and extend lifespan in various species. The effect of caloric restriction appears to be related to a reduction in cellular damage induced by reactive oxygen species. There is increasing evidence that sirtuins play an essential role in the reduction of mitochondrial oxidative stress during caloric restriction. We speculate that cardiac sirtuins attenuate the accumulation of oxidative damage associated with age by modifying specific mitochondrial proteins posttranscriptionally. Therefore, the distinct role of each sirtuin in the heart subjected to caloric restriction should be clarified to translate sirtuin biology into clinical practice.

  14. SIRT2 deacetylates FOXO3a in response to oxidative stress and caloric restriction

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    The sirtuin family of nicotinamide adenine dinucleotide-dependent (NAD) deacetylases plays an important role in aging and metabolic regulation. In yeast, the Sir2 gene and its homolog Hst2 independently mediate the action of caloric restriction on lifespan extension. The mammalian Sir2 ortholog, SIR...

  15. Thermoregulatory, Cardiovascular, and Metabolic Responses to Mild Caloric Restriction in the Brown Norway Rat

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    Caloric restriction (CR) has been demonstrated to prolong the life span of a variety of species. CR-induced reduction in core temperature (Tc) is considered a key mechanism responsible for prolonging life span in rodents; however, little is known on the regulation of CR-induced h...

  16. Mitochondrial oxidative stress, aging and caloric restriction: the protein and methionine connection.

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    Pamplona, Reinald; Barja, Gustavo

    2006-01-01

    Caloric restriction (CR) decreases aging rate and mitochondrial ROS (MitROS) production and oxidative stress in rat postmitotic tissues. Low levels of these parameters are also typical traits of long-lived mammals and birds. However, it is not known what dietary components are responsible for these changes during CR. It was recently observed that 40% protein restriction without strong CR also decreases MitROS generation and oxidative stress. This is interesting because protein restriction also increases maximum longevity (although to a lower extent than CR) and is a much more practicable intervention for humans than CR. Moreover, it was recently found that 80% methionine restriction substituting it for l-glutamate in the diet also decreases MitROS generation in rat liver. Thus, methionine restriction seems to be responsible for the decrease in ROS production observed in caloric restriction. This is interesting because it is known that exactly that procedure of methionine restriction also increases maximum longevity. Moreover, recent data show that methionine levels in tissue proteins negatively correlate with maximum longevity in mammals and birds. All these suggest that lowering of methionine levels is involved in the control of mitochondrial oxidative stress and vertebrate longevity by at least two different mechanisms: decreasing the sensitivity of proteins to oxidative damage, and lowering of the rate of ROS generation at mitochondria.

  17. Caloric restriction and intermittent fasting: Two potential diets for successful brain aging

    OpenAIRE

    Martin, Bronwen; Mark P. Mattson; Maudsley, Stuart

    2006-01-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical meta...

  18. Caloric restriction in lean and obese strains of laboratory rat: effects on body composition, metabolism, growth and overall health

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    U.S. Environmental Protection Agency — Data related to obese and lean strains of rat commonly used in the laboratory that are calorically restricted and its effects on physiologic parameters (Body...

  19. Targeting energy metabolism in brain cancer with calorically restricted ketogenic diets.

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    Seyfried, Thomas N; Kiebish, Michael; Mukherjee, Purna; Marsh, Jeremy

    2008-11-01

    Information is presented on the calorically restricted ketogenic diet (CRKD) as an alternative therapy for brain cancer. In contrast to normal neurons and glia, which evolved to metabolize ketone bodies as an alternative fuel to glucose under energy-restricted conditions, brain tumor cells are largely glycolytic due to mitochondrial defects and have a reduced ability to metabolize ketone bodies. The CRKD is effective in managing brain tumor growth in animal models and in patients, and appears to act through antiangiogenic, anti-inflammatory, and proapoptotic mechanisms.

  20. Caloric restriction in C57BL/6J mice mimics therapeutic fasting in humans

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    Denny Christine A

    2006-05-01

    Full Text Available Abstract Background Caloric restriction (CR has long been recognized as a dietary therapy that improves health and increases longevity. Little is known about the persistent effects of CR on plasma biomarkers (glucose, ketone bodies, and lipids following re-feeding in mice. It is also unclear how these biomarker changes in calorically restricted mice relate to those observed previously in calorically restricted humans. Results Three groups of individually housed adult female C57BL/6J (B6 mice (n = 4/group were fed a standard rodent chow diet either: (1 unrestricted (UR; (2 restricted for three weeks to reduce body weight by approximately 15–20% (R; or (3 restricted for three weeks and then re-fed unrestricted (ad libitum for an additional three weeks (R-RF. Body weight and food intake were measured throughout the study, while plasma lipids and levels of glucose and ketone bodies (β-hydroxybutyrate were measured at the termination of the study. Plasma glucose, phosphatidylcholine, cholesterol, and triglycerides were significantly lower in the R mice than in the UR mice. In contrast, plasma fatty acids and β-hydroxybutyrate were significantly higher in the R mice than in the UR mice. CR had no effect on plasma phosphatidylinositol levels. While body weight and plasma lipids of the R-RF mice returned to unrestricted levels upon re-feeding, food intake and glucose levels remained significantly lower than those prior to the initiation of CR. Conclusion CR establishes a new homeostatic state in B6 mice that persists for at least three weeks following ad libitum re-feeding. Moreover, the plasma biomarker changes observed in B6 mice during CR mimic those reported in humans on very low calorie diets or during therapeutic fasting.

  1. Caloric restriction and resveratrol promote longevity through the Sirtuin-1-dependent induction of autophagy.

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    Morselli, E; Maiuri, M C; Markaki, M; Megalou, E; Pasparaki, A; Palikaras, K; Criollo, A; Galluzzi, L; Malik, S A; Vitale, I; Michaud, M; Madeo, F; Tavernarakis, N; Kroemer, G

    2010-01-01

    Caloric restriction and autophagy-inducing pharmacological agents can prolong lifespan in model organisms including mice, flies, and nematodes. In this study, we show that transgenic expression of Sirtuin-1 induces autophagy in human cells in vitro and in Caenorhabditis elegans in vivo. The knockdown or knockout of Sirtuin-1 prevented the induction of autophagy by resveratrol and by nutrient deprivation in human cells as well as by dietary restriction in C. elegans. Conversely, Sirtuin-1 was not required for the induction of autophagy by rapamycin or p53 inhibition, neither in human cells nor in C. elegans. The knockdown or pharmacological inhibition of Sirtuin-1 enhanced the vulnerability of human cells to metabolic stress, unless they were stimulated to undergo autophagy by treatment with rapamycin or p53 inhibition. Along similar lines, resveratrol and dietary restriction only prolonged the lifespan of autophagy-proficient nematodes, whereas these beneficial effects on longevity were abolished by the knockdown of the essential autophagic modulator Beclin-1. We conclude that autophagy is universally required for the lifespan-prolonging effects of caloric restriction and pharmacological Sirtuin-1 activators.

  2. The calorically restricted ketogenic diet, an effective alternative therapy for malignant brain cancer

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    Zhou Weihua

    2007-02-01

    Full Text Available Abstract Background Malignant brain cancer persists as a major disease of morbidity and mortality in adults and is the second leading cause of cancer death in children. Many current therapies for malignant brain tumors fail to provide long-term management because they ineffectively target tumor cells while negatively impacting the health and vitality of normal brain cells. In contrast to brain tumor cells, which lack metabolic flexibility and are largely dependent on glucose for growth and survival, normal brain cells can metabolize both glucose and ketone bodies for energy. This study evaluated the efficacy of KetoCal®, a new nutritionally balanced high fat/low carbohydrate ketogenic diet for children with epilepsy, on the growth and vascularity of a malignant mouse astrocytoma (CT-2A and a human malignant glioma (U87-MG. Methods Adult mice were implanted orthotopically with the malignant brain tumors and KetoCal® was administered to the mice in either unrestricted amounts or in restricted amounts to reduce total caloric intake according to the manufacturers recommendation for children with refractory epilepsy. The effects KetoCal® on tumor growth, vascularity, and mouse survival were compared with that of an unrestricted high carbohydrate standard diet. Results KetoCal® administered in restricted amounts significantly decreased the intracerebral growth of the CT-2A and U87-MG tumors by about 65% and 35%, respectively, and significantly enhanced health and survival relative to that of the control groups receiving the standard low fat/high carbohydrate diet. The restricted KetoCal® diet reduced plasma glucose levels while elevating plasma ketone body (β-hydroxybutyrate levels. Tumor microvessel density was less in the calorically restricted KetoCal® groups than in the calorically unrestricted control groups. Moreover, gene expression for the mitochondrial enzymes, β-hydroxybutyrate dehydrogenase and succinyl-CoA: 3-ketoacid Co

  3. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas.

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    Abedelmalek, Salma; Chtourou, Hamdi; Souissi, Nizar; Tabka, Zouhair

    2015-01-01

    The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg) participate in this study during a period of weight maintenance (baseline) and after 7 days of caloric restriction (CR). All subjects performed the Special Judo Fitness Test (SJFT) during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (-5~6 MJ/day). Our results showed that CR resulted in significant decreases in body weight (P exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH), leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P < 0.05). Additionally, CR leads to an increase in cortisol and GH (P < 0.05) and a decrease in testosterone concentrations (P < 0.05).

  4. Caloric Restriction Effect on Proinflammatory Cytokines, Growth Hormone, and Steroid Hormone Concentrations during Exercise in Judokas

    Directory of Open Access Journals (Sweden)

    Salma Abedelmalek

    2015-01-01

    Full Text Available The aim of this study was to evaluate the effect of caloric restriction on the immune and hormonal responses during exercise in judo athletes. In a randomised order, 11 male judokas (age: 20.45 ± 0.51; height: 1.71 ± 0.3 m; and body weight: 75.9 ± 3.1 kg participate in this study during a period of weight maintenance (baseline and after 7 days of caloric restriction (CR. All subjects performed the Special Judo Fitness Test (SJFT during the two conditions. Values for nutrient intakes were obtained from a 7 d food record kept during a period of weight maintenance and after a 7-day food restriction (−5~6 MJ/day. Our results showed that CR resulted in significant decreases in body weight (P<0.05 and performance (P<0.05. However, heart rate and SJFT index (P<0.05 increase significantly during CR in comparison to baseline. Moreover, exercise leads to a significant increase in testosterone, cortisol, growth hormone (GH, leukocytes, neutrophils, TNF-α, and IL-6, in both CR and baseline conditions. Compared to baseline, TNF-α and IL-6 were significantly higher during CR condition (P<0.05. Additionally, CR leads to an increase in cortisol and GH (P<0.05 and a decrease in testosterone concentrations (P<0.05.

  5. Caloric restriction promotes cell survival in a mouse model of normal tension glaucoma

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    Guo, Xiaoli; Kimura, Atsuko; Azuchi, Yuriko; Akiyama, Goichi; Noro, Takahiko; Harada, Chikako; Namekata, Kazuhiko; Harada, Takayuki

    2016-01-01

    Glaucoma is characterized by progressive degeneration of retinal ganglion cells (RGCs) and their axons. We previously reported that loss of glutamate transporters (EAAC1 or GLAST) in mice leads to RGC degeneration that is similar to normal tension glaucoma and these animal models are useful in examining potential therapeutic strategies. Caloric restriction has been reported to increase longevity and has potential benefits in injury and disease. Here we investigated the effects of every-other-day fasting (EODF), a form of caloric restriction, on glaucomatous pathology in EAAC1−/− mice. EODF suppressed RGC death and retinal degeneration without altering intraocular pressure. Moreover, visual impairment was ameliorated with EODF, indicating the functional significance of the neuroprotective effect of EODF. Several mechanisms associated with this neuroprotection were explored. We found that EODF upregulated blood β-hydroxybutyrate levels and increased histone acetylation in the retina. Furthermore, it elevated retinal mRNA expression levels of neurotrophic factors and catalase, whereas it decreased oxidative stress levels in the retina. Our findings suggest that EODF, a safe, non-invasive, and low-cost treatment, may be available for glaucoma therapy. PMID:27669894

  6. Caloric restriction suppresses apoptotic cell death in the mammalian cochlea and leads to prevention of presbycusis.

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    Someya, Shinichi; Yamasoba, Tatsuya; Weindruch, Richard; Prolla, Tomas A; Tanokura, Masaru

    2007-10-01

    Presbycusis is characterized by an age-related progressive decline of auditory function, and arises mainly from the degeneration of hair cells or spiral ganglion (SG) cells in the cochlea. Here we show that caloric restriction suppresses apoptotic cell death in the mouse cochlea and prevents late onset of presbycusis. Calorie restricted (CR) mice, which maintained body weight at the same level as that of young control (YC) mice, retained normal hearing and showed no cochlear degeneration. CR mice also showed a significant reduction in the number of TUNEL-positive cells and cleaved caspase-3-positive cells relative to middle-age control (MC) mice. Microarray analysis revealed that CR down-regulated the expression of 24 apoptotic genes, including Bak and Bim. Taken together, our findings suggest that loss of critical cells through apoptosis is an important mechanism of presbycusis in mammals, and that CR can retard this process by suppressing apoptosis in the inner ear tissue.

  7. Protective effects of estrogens and caloric restriction during aging on various rat testis parameters

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdelfattah ElFek; Serge Carreau

    2008-01-01

    Aim: To investigate the effects of 17β-estradiol (E2), Peganum harmala extract (PHE) and caloric restriction (CR) on various testis parameters during aging. Methods: Twelve-month-old male rats were treated for 6 months with either E2 or PHE, or submitted to CR (40%). Results: Our results show that estrogens and CR are able to protect the male gonad by preventing the decrease of testosterone and E2 levels as well as the decrease of aromatase and estrogen receptor gene expressions. Indeed, E2, PHE and CR treatments induced an increase in the superoxide dismutase activities and decreased the activity of testicular enzymes: gamma-glutamyl transferase, alkaline phosphatase, lactate deshydrogenase as well as the aspartate and lactate transaminases in aged animals. In addition, the testicular catalase and gluthatione peroxidase activities were enhanced in E2, PHE and CR-treated rats compared to untreated animals at 18 months of age. Moreover, the positive effects of estradiol, PHE and CR were further supported by a lower level of lipid peroxidation. Recovery of spermatogenesis was recorded in treated rats. Conclusion: Besides a low caloric diet which is beneficial for spermatogenesis, a protective antioxydant role of estrogens is suggested. Estrogens delay testicular cell damage, which leads to functional senescence and, therefore, estrogens are helpful in protecting the reproductive functions from the adverse effects exerted by reactive oxygen species (ROS) produced in large quanti-ties in the aged testis.

  8. Caloric Restriction in Lean and Obese Strains of Laboratory Rat: Effects on Body Composition, Metabolism, Growth, and Overall Health

    Science.gov (United States)

    NEW FINDINGS: What is the central question of this study? How do lean and obese rats respond physiologically to caloric restriction? What is the main finding and its importance? Obese rats show marked benefits compared with lean animals. Reduced body fat is associated with improv...

  9. Cardiovascular flexibility in middle-aged overweight South Asians vs. white Caucasians: response to short-term caloric restriction

    NARCIS (Netherlands)

    Schinkel, L.D. van; Bakker, L.E.; Jonker, J.T.; Roos, A. de; Pijl, H.; Meinders, A.E.; Jazet, I.M.; Lamb, H.J.; Smit, J.W.A.

    2015-01-01

    BACKGROUND AND AIMS: South Asians have a higher risk of developing cardiovascular disease than white Caucasians. The underlying cause is unknown, but might be related to higher cardiac susceptibility to metabolic disorders. Short-term caloric restriction (CR) can be used as a metabolic stress test t

  10. Behavioural changes are a major contributing factor in the reduction of sarcopenia in caloric-restricted ageing mice

    NARCIS (Netherlands)

    Norren, van K.; Rusli, F.; Dijk, van M.; Lute, C.; Nagel, J.C.; Dijk, F.J.; Dwarkasing, J.T.; Boekschoten, M.V.; Luiking, Y.; Witkamp, R.F.; Müller, M.R.; Steegenga, W.T.

    2015-01-01

    Background - In rodent models, caloric restriction (CR) with maintenance of adequate micronutrient supply has been reported to increase lifespan and to reduce age-induced muscle loss (sarcopenia) during ageing. In the present study, we further investigated effects of CR on the onset and severity of

  11. Exercise and Caloric Restriction Alter the Immune System of Mice Submitted to a High-Fat Diet

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    Frederick Wasinski

    2013-01-01

    Full Text Available As the size of adipocytes increases during obesity, the establishment of resident immune cells in adipose tissue becomes an important source of proinflammatory mediators. Exercise and caloric restriction are two important, nonpharmacological tools against body mass increase. To date, their effects on the immune cells of adipose tissue in obese organisms, specifically when a high-fat diet is consumed, have been poorly investigated. Thus, after consuming a high-fat diet, mice were submitted to chronic swimming training or a 30% caloric restriction in order to investigate the effects of both interventions on resident immune cells in adipose tissue. These strategies were able to reduce body mass and resulted in changes in the number of resident immune cells in the adipose tissue and levels of cytokines/chemokines in serum. While exercise increased the number of NK cells in adipose tissue and serum levels of IL-6 and RANTES, caloric restriction increased the CD4+/CD8+ cell ratio and MCP-1 levels. Together, these data demonstrated that exercise and caloric restriction modulate resident immune cells in adipose tissues differently in spite of an equivalent body weight reduction. Additionally, the results also reinforce the idea that a combination of both strategies is better than either individually for combating obesity.

  12. A two year randomized controlled trial of human caloric restriction: feasibility and effects on predictors of health span and longevity

    Science.gov (United States)

    Background: Caloric restriction (CR), energy intake reduced below ad libitum (AL) intake, increases life span in many species. The implications for humans can be clarified by randomized controlled trials of CR. Methods: To determine CRs feasibility, safety, and effects on predictors of longevity, di...

  13. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

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    Elizabeth K. Parker

    2016-01-01

    Full Text Available Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD age of the 162 adolescents was 16.7 years (0.9, admission % median BMI was 80.1% (10.2, and discharge % median BMI was 93.1% (7.0. The mean (SD starting caloric intake was 2611.7 kcal/day (261.5 equating to 58.4 kcal/kg (10.2. Most patients (92.6% were treated with nasogastric tube feeding. The mean (SD length of stay was 3.6 weeks (1.9, and average weekly weight gain was 2.1 kg (0.8. No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (<0.75 mmol/L, 7% hypomagnesaemia (<0.70 mmol/L, and 2% hypokalaemia (<3.2 mmol/L. Caloric prescription on admission was associated with developing oedema (95% CI 1.001 to 1.047; p=0.039. No statistical significance was found between electrolytes and calories provided during refeeding. Conclusion. A rapid refeeding protocol with the inclusion of phosphate supplementation can safely achieve rapid weight restoration without increased complications associated with refeeding syndrome.

  14. Maintenance of cellular ATP level by caloric restriction correlates chronological survival of budding yeast

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Joon-Seok; Lee, Cheol-Koo, E-mail: cklee2005@korea.ac.kr

    2013-09-13

    Highlights: •CR decreases total ROS and mitochondrial superoxide during the chronological aging. •CR does not affect the levels of oxidative damage on protein and DNA. •CR contributes extension of chronological lifespan by maintenance of ATP level -- Abstract: The free radical theory of aging emphasizes cumulative oxidative damage in the genome and intracellular proteins due to reactive oxygen species (ROS), which is a major cause for aging. Caloric restriction (CR) has been known as a representative treatment that prevents aging; however, its mechanism of action remains elusive. Here, we show that CR extends the chronological lifespan (CLS) of budding yeast by maintaining cellular energy levels. CR reduced the generation of total ROS and mitochondrial superoxide; however, CR did not reduce the oxidative damage in proteins and DNA. Subsequently, calorie-restricted yeast had higher mitochondrial membrane potential (MMP), and it sustained consistent ATP levels during the process of chronological aging. Our results suggest that CR extends the survival of the chronologically aged cells by improving the efficiency of energy metabolism for the maintenance of the ATP level rather than reducing the global oxidative damage of proteins and DNA.

  15. Entropy Generation and Human Aging: Lifespan Entropy and Effect of Diet Composition and Caloric Restriction Diets

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    Carlos A. Silva

    2009-01-01

    Full Text Available The first and second laws of thermodynamic were applied to statistical databases on nutrition and human growth in order to estimate the entropy generation over the human lifespan. The calculations were performed for the cases of variation in the diet composition and calorie restriction diets; and results were compared to a base case in which lifespan entropy generation was found to be 11 404 kJ/K per kg of body mass, predicting a lifespan of 73.78 and 81.61 years for the average male and female individuals respectively. From the analysis of the results, it was found that changes of diet % of fat and carbohydrates do not have a significant impact on predicted lifespan, while the diet % of proteins has an important effect. Reduction of diet protein % to the minimum recommended in nutrition literature yields an average increase of 3.3 years on the predicted lifespan. Changes in the calorie content of the diet also have an important effect, yielding a % increase in lifespan equal or higher than the % reduction in the diet caloric content. This correlates well experimental data on small mammal and insects, in which lifespan has been increased by diet restriction.

  16. Effect of caloric restriction on myenteric neuroplasticity in the rat duodenum during aging.

    Science.gov (United States)

    da Silva Porto, Gisele; Bertaglia Pereira, Joice Naiara; Tibúrcio, Vanessa Graciele; Stabille, Sandra Regina; Garcia de Faria, Haroldo; de Melo Germano, Ricardo; de Britto Mari, Renata

    2012-05-21

    The objective of this study was to evaluate the effects of caloric restriction (CR) on myenteric neurons in the duodenum of Wistar rats during aging. Thirty rats were divided into three groups: the C group (six-month-old animals that were fed a normal diet from weaning until six months of age), the SR group (18-month-old animals that were fed a normal diet from weaning until 18 months of age) and the CR group (18-month-old animals that were fed a 30% CR diet after six months of age). After 12 months, the animals were euthanized. Whole-mount preparations of the duodenums were either stained with Giemsa or underwent NADPH-diaphorase histochemistry to determine the general myenteric neuron population and the nitrergic neuron subpopulation (NADPH-d+), respectively. The NADPH-d-negative (NADPH-d-) neuron population was estimated based on the difference between the Giemsa-stained and NADPH-d+ neurons. The neurons were counted, and the cell body areas were measured. Aging was associated with neuronal loss in the SR group, which was minimized by caloric restriction in the CR group. The density (mm(2)) of the Giemsa-stained neurons was higher in the SR group (79.09 ± 6.25) than in the CR (92.37 ± 11.6) and C (111.68 ± 15.26) groups. The density of the NADPH-d+ neurons was higher in the SR group (44.90 ± 5.88) than in the C (35.75 ± 1.6) and RC (39.14 ± 7.02) groups. The density of NADPH-d- neurons was higher in the CR (49.73 ± 12.08) and C (75.64 ± 17.05) groups than in the SR group (33.82 ± 4.5). In the C group, 32% and 68% of the Giemsa-stained myenteric neurons were NADPH-d+ or NADPH-d-, respectively. With aging (SR group), the percentage of nitrergic neurons (56.77%) increased, whereas the percentage of NADPH-d- neurons (43.22%) decreased. In the CR group, the change in the percentage of nitrergic (42.37%) and NADPH-d- (57.62%) neurons was lower. As NADPH-d- neurons will be mostly cholinergic neurons, CR appears to reduce the loss of cholinergic neurons during

  17. Accumulation of long-chain glycosphingolipids during aging is prevented by caloric restriction.

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    María José Hernández-Corbacho

    Full Text Available BACKGROUND: Chronic kidney disease and end-stage renal disease are major causes of morbidity and mortality that are seen far more commonly in the aged population. Interestingly, kidney function declines during aging even in the absence of underlying renal disease. Declining renal function has been associated with age-related cellular damage and dysfunction with reports of increased levels of apoptosis, necrosis, and inflammation in the aged kidney. Bioactive sphingolipids have been shown to regulate these same cellular processes, and have also been suggested to play a role in aging and cellular senescence. METHODOLOGY/PRINCIPAL FINDINGS: We hypothesized that alterations in kidney sphingolipids play a role in the declining kidney function that occurs during aging. To begin to address this, the sphingolipid profile was measured in young (3 mo, middle aged (9 mo and old (17 mo C57BL/6 male mice. Interestingly, while modest changes in ceramides and sphingoid bases were evident in kidneys from older mice, the most dramatic elevations were seen in long-chain hexosylceramides (HexCer and lactosylceramides (LacCer, with C14- and C16-lactosylceramides elevated as much as 8 and 12-fold, respectively. Increases in long-chain LacCers during aging are not exclusive to the kidney, as they also occur in the liver and brain. Importantly, caloric restriction, previously shown to prevent the declining kidney function seen in aging, inhibits accumulation of long-chain HexCer/LacCers and prevents the age-associated elevation of enzymes involved in their synthesis. Additionally, long-chain LacCers are also significantly elevated in human fibroblasts isolated from elderly individuals. CONCLUSION/SIGNIFICANCE: This study demonstrates accumulation of the glycosphingolipids HexCer and LacCer in several different organs in rodents and humans during aging. In addition, data demonstrate that HexCer and LacCer metabolism is regulated by caloric restriction. Taken together

  18. The Impact of Exercise Training Compared to Caloric Restriction on Hepatic and Peripheral Insulin Resistance in Obesity

    Science.gov (United States)

    Coker, Robert H.; Williams, Rick H.; Yeo, Sophie E.; Kortebein, Patrick M.; Bodenner, Don L.; Kern, Philip A.; Evans, William J.

    2009-01-01

    Context: It has been difficult to distinguish the independent effects of caloric restriction versus exercise training on insulin resistance. Objective: Utilizing metabolic feeding and supervised exercise training, we examined the influence of caloric restriction vs. exercise training with and without weight loss on hepatic and peripheral insulin resistance. Design, Participants, and Intervention: Thirty-four obese, older subjects were randomized to: caloric restriction with weight loss (CR), exercise training with weight loss (EWL), exercise training without weight loss (EX), or controls. Based on an equivalent caloric deficit in EWL and CR, we induced matched weight loss. Subjects in the EX group received caloric compensation. Combined with [6,62H2]glucose, an octreotide, glucagon, multistage insulin infusion was performed to determine suppression of glucose production (SGP) and insulin-stimulated glucose disposal (ISGD). Computed tomography scans were performed to assess changes in fat distribution. Results: Body weight decreased similarly in EWL and CR, and did not change in EX and controls. The reduction in visceral fat was significantly greater in EWL (−71 ± 15 cm2) compared to CR and EX. The increase in SGP was also almost 3-fold greater (27 ± 2%) in EWL. EWL and CR promoted similar improvements in ISGD [+2.5 ± 0.4 and 2.4 ± 0.9 mg · kg fat-free mass (FFM)−1 · min−1], respectively. Conclusions: EWL promoted the most significant reduction in visceral fat and the greatest improvement in SGP. Equivalent increases in ISGD were noted in EWL and CR, whereas EX provided a modest improvement. Based on our results, EWL promoted the optimal intervention-based changes in body fat distribution and systemic insulin resistance. PMID:19808853

  19. [Caloric restriction in primates: how efficient as an anti-aging approach?].

    Science.gov (United States)

    Marchal, Julia; Perret, Martine; Aujard, Fabienne

    2012-12-01

    Caloric restriction (CR) is the only non-genetic intervention known to date to slow the onset of age-related diseases and increase average and maximum lifespan in several species. Its interest is continually growing, particularly for the identification of mechanisms involved in increasing longevity. Unlike studies in invertebrate and rodent models have provided some indication about the mechanisms of the CR, the efficacy of CR as an anti-aging protocol in primates has not yet been fully established. In this review we present the advantages of using non human primates as relevant models to the study of human aging in general and specifically in the context of therapeutic interventions applicable to humans, such as CR. Through the longitudinal findings in the Grey Mouse Lemur (Microcebus murinus), we stress the importance of primate studies in the context of research on aging and their potential to advance the development of molecules which can mimic the beneficial effects of CR, already observed in some species, without imposing a reduced calorie diet.

  20. Caloric restriction reveals a metabolomic and lipidomic signature in liver of male mice.

    Science.gov (United States)

    Jové, Mariona; Naudí, Alba; Ramírez-Núñez, Omar; Portero-Otín, Manuel; Selman, Colin; Withers, Dominic J; Pamplona, Reinald

    2014-10-01

    Lipid composition, particularly membrane unsaturation, has been proposed as being a lifespan determinant, but it is currently unknown whether caloric restriction (CR), an accepted life-extending intervention, affects cellular lipid profiles. In this study, we employ a liquid chromatography quadrupole time-of-flight-based methodology to demonstrate that CR in the liver of male C57BL/6 mice: (i) induces marked changes in the cellular lipidome, (ii) specifically reduces levels of a phospholipid peroxidation product, 1-palmitoyl-2-glutaryl-sn-glycero-3-phosphatidylcholine, (iii) alters cellular phosphoethanolamine and triglyceride distributional profiles, (iv) affects mitochondrial electron transport chain complexes, increasing complex II and decreasing complex III and (v) is associated with specific changes in liver metabolic pathways. These data demonstrate that CR induces a specific lipidome and metabolome reprogramming event in mouse liver which is associated with lower protein oxidative damage, as assessed by mass spectrometry-based measurements. Such changes may be critical to the increased lifespan and healthspan observed in C57BL/6 mice following CR.

  1. Whole-transcriptome analysis of mouse adipose tissue in response to short-term caloric restriction.

    Science.gov (United States)

    Kim, Seung-Soo; Choi, Kyung-Mi; Kim, Soyoung; Park, Taesun; Cho, In-Cheol; Lee, Jae-Won; Lee, Cheol-Koo

    2016-04-01

    Caloric restriction (CR) has been shown to extend the lifespan of many species by improving cellular function and organismal health. Additionally, fat reduction by CR may play an important role in lengthening lifespan and preventing severe age-related diseases. Interestingly, CR induced the greatest transcriptome change in the epididymal fat of mice in our study. In this transcriptome analysis, we identified and categorized 446 genes that correlated with CR level. We observed down-regulation of several signaling pathways, including insulin/insulin-like growth factor 1 (insulin/IGF-1), epidermal growth factor (EGF), transforming growth factor beta (TGF-β), and canonical wingless-type mouse mammary tumor virus integration site (Wnt). Many genes related to structural features, including extracellular matrix structure, cell adhesion, and the cytoskeleton, were down-regulated, with a strong correlation to the degree of CR. Furthermore, genes related to the cell cycle and adipogenesis were down-regulated. These biological processes are well-identified targets of insulin/IGF-1, EGF, TGF-β, and Wnt signaling. In contrast, genes involved in specific metabolic processes, including the tricarboxylic acid cycle and the electron transport chain were up-regulated. We performed in silico analysis of the promoter sequences of CR-responsive genes and identified two associated transcription factors, Paired-like homeodomain 2 (Pitx2) and Paired box gene 6 (Pax6). Our results suggest that strict regulation of signaling pathways is critical for creating the optimal energy homeostasis to extend lifespan.

  2. Caloric restriction increases ketone bodies metabolism and preserves blood flow in aging brain.

    Science.gov (United States)

    Lin, Ai-Ling; Zhang, Wei; Gao, Xiaoli; Watts, Lora

    2015-07-01

    Caloric restriction (CR) has been shown to increase the life span and health span of a broad range of species. However, CR effects on in vivo brain functions are far from explored. In this study, we used multimetric neuroimaging methods to characterize the CR-induced changes of brain metabolic and vascular functions in aging rats. We found that old rats (24 months of age) with CR diet had reduced glucose uptake and lactate concentration, but increased ketone bodies level, compared with the age-matched and young (5 months of age) controls. The shifted metabolism was associated with preserved vascular function: old CR rats also had maintained cerebral blood flow relative to the age-matched controls. When investigating the metabolites in mitochondrial tricarboxylic acid cycle, we found that citrate and α-ketoglutarate were preserved in the old CR rats. We suggest that CR is neuroprotective; ketone bodies, cerebral blood flow, and α-ketoglutarate may play important roles in preserving brain physiology in aging.

  3. Krebs cycle enzymes from livers of old mice are differentially regulated by caloric restriction.

    Science.gov (United States)

    Hagopian, Kevork; Ramsey, Jon J; Weindruch, Richard

    2004-08-01

    Krebs cycle enzyme activities and levels of five metabolites were determined from livers of old mice (30 months) maintained either on control or on long-term caloric restriction (CR) diets (28 months). In CR mice, the cycle was divided into two major blocks, the first containing citrate synthase, aconitase and NAD-dependent isocitrate dehydrogenase which showed decreased activities, while the second block, containing the remaining enzymes, displayed increased activity (except for fumarase, which was unchanged). CR also resulted in decreased levels of citrate, glutamate and alpha-ketoglutarate, increased levels of malate, and unchanged levels of aspartate. The alpha-ketoglutarate/glutamate and malate/alpha-ketoglutarate ratios were higher in CR, in parallel with previously reported increases with CR in pyruvate carboxylase activity and glucagon levels, respectively. The results indicate that long-term CR induces a differential regulation of Krebs cycle in old mice and this regulation may be the result of changes in gene expression levels, as well as a complex interplay between enzymes, hormones and other effectors. Truncation of Krebs cycle by CR may be an important adaptation to utilize available substrates for the gluconeogenesis necessary to sustain glycolytic tissues, such as brain.

  4. Higher Caloric Refeeding Is Safe in Hospitalised Adolescent Patients with Restrictive Eating Disorders

    Science.gov (United States)

    Parker, Elizabeth K.; Faruquie, Sahrish S.; Anderson, Gail; Gomes, Linette; Kennedy, Andrew; Wearne, Christine M.; Kohn, Michael R.; Clarke, Simon D.

    2016-01-01

    Introduction. This study examines weight gain and assesses complications associated with refeeding hospitalised adolescents with restrictive eating disorders (EDs) prescribed initial calories above current recommendations. Methods. Patients admitted to an adolescent ED structured “rapid refeeding” program for >48 hours and receiving ≥2400 kcal/day were included in a 3-year retrospective chart review. Results. The mean (SD) age of the 162 adolescents was 16.7 years (0.9), admission % median BMI was 80.1% (10.2), and discharge % median BMI was 93.1% (7.0). The mean (SD) starting caloric intake was 2611.7 kcal/day (261.5) equating to 58.4 kcal/kg (10.2). Most patients (92.6%) were treated with nasogastric tube feeding. The mean (SD) length of stay was 3.6 weeks (1.9), and average weekly weight gain was 2.1 kg (0.8). No patients developed cardiac signs of RFS or delirium; complications included 4% peripheral oedema, 1% hypophosphatemia (refeeding syndrome. PMID:27293884

  5. Measuring aging rates of mice subjected to caloric restriction and genetic disruption of growth hormone signaling

    Science.gov (United States)

    Koopman, Jacob J.E.; van Heemst, Diana; van Bodegom, David; Bonkowski, Michael S.; Sun, Liou Y.; Bartke, Andrzej

    2016-01-01

    Caloric restriction and genetic disruption of growth hormone signaling have been shown to counteract aging in mice. The effects of these interventions on aging are examined through age-dependent survival or through the increase in age-dependent mortality rates on a logarithmic scale fitted to the Gompertz model. However, these methods have limitations that impede a fully comprehensive disclosure of these effects. Here we examine the effects of these interventions on murine aging through the increase in age-dependent mortality rates on a linear scale without fitting them to a model like the Gompertz model. Whereas these interventions negligibly and non-consistently affected the aging rates when examined through the age-dependent mortality rates on a logarithmic scale, they caused the aging rates to increase at higher ages and to higher levels when examined through the age-dependent mortality rates on a linear scale. These results add to the debate whether these interventions postpone or slow aging and to the understanding of the mechanisms by which they affect aging. Since different methods yield different results, it is worthwhile to compare their results in future research to obtain further insights into the effects of dietary, genetic, and other interventions on the aging of mice and other species. PMID:26959761

  6. Caloric restriction and intermittent fasting: two potential diets for successful brain aging.

    Science.gov (United States)

    Martin, Bronwen; Mattson, Mark P; Maudsley, Stuart

    2006-08-01

    The vulnerability of the nervous system to advancing age is all too often manifest in neurodegenerative disorders such as Alzheimer's and Parkinson's diseases. In this review article we describe evidence suggesting that two dietary interventions, caloric restriction (CR) and intermittent fasting (IF), can prolong the health-span of the nervous system by impinging upon fundamental metabolic and cellular signaling pathways that regulate life-span. CR and IF affect energy and oxygen radical metabolism, and cellular stress response systems, in ways that protect neurons against genetic and environmental factors to which they would otherwise succumb during aging. There are multiple interactive pathways and molecular mechanisms by which CR and IF benefit neurons including those involving insulin-like signaling, FoxO transcription factors, sirtuins and peroxisome proliferator-activated receptors. These pathways stimulate the production of protein chaperones, neurotrophic factors and antioxidant enzymes, all of which help cells cope with stress and resist disease. A better understanding of the impact of CR and IF on the aging nervous system will likely lead to novel approaches for preventing and treating neurodegenerative disorders.

  7. Better Living through Chemistry: Caloric Restriction (CR) and CR Mimetics Alter Genome Function to Promote Increased Health and Lifespan

    Science.gov (United States)

    Gillespie, Zoe E.; Pickering, Joshua; Eskiw, Christopher H.

    2016-01-01

    Caloric restriction (CR), defined as decreased nutrient intake without causing malnutrition, has been documented to increase both health and lifespan across numerous organisms, including humans. Many drugs and other compounds naturally occurring in our diet (nutraceuticals) have been postulated to act as mimetics of caloric restriction, leading to a wave of research investigating the efficacy of these compounds in preventing age-related diseases and promoting healthier, longer lifespans. Although well studied at the biochemical level, there are still many unanswered questions about how CR and CR mimetics impact genome function and structure. Here we discuss how genome function and structure are influenced by CR and potential CR mimetics, including changes in gene expression profiles and epigenetic modifications and their potential to identify the genetic fountain of youth. PMID:27588026

  8. Effects of age and caloric restriction in the vascular response of renal arteries to endothelin-1 in rats.

    Science.gov (United States)

    Amor, Sara; García-Villalón, Angel Luis; Rubio, Carmen; Carrascosa, Jose Ma; Monge, Luis; Fernández, Nuria; Martín-Carro, Beatriz; Granado, Miriam

    2017-02-01

    Cardiovascular alterations are the most prevalent cause of impaired physiological function in aged individuals with kidney being one the most affected organs. Aging-induced alterations in renal circulation are associated with a decrease in endothelium-derived relaxing factors such as nitric oxide (NO) and with an increase in contracting factors such as endothelin-1(ET-1). As caloric restriction (CR) exerts beneficial effects preventing some of the aging-induced alterations in cardiovascular system, the aim of this study was to analyze the effects of age and caloric restriction in the vascular response of renal arteries to ET-1 in aged rats. Vascular function was studied in renal arteries from 3-month-old Wistar rats fed ad libitum (3m) and in renal arteries from 8-and 24-month-old Wistar rats fed ad libitum (8m and 24m), or subjected to 20% caloric restriction during their three last months of life (8m-CR and 24m-CR). The contractile response to ET-1 was increased in renal arteries from 8m and 24m compared to 3m rats. ET-1-induced contraction was mediated by ET-A receptors in all experimental groups and also by ET-B receptors in 24m rats. Caloric restriction attenuated the increased contraction to ET-1 in renal arteries from 8m but not from 24m rats possibly through NO release proceeding from ET-B endothelial receptors. In 24m rats, CR did not attenuate the aging-increased response of renal arteries to ET-1, but it prevented the aging-induced increase in iNOS mRNA levels and the aging-induced decrease in eNOS mRNA levels in arterial tissue. In conclusion, aging is associated with an increased response to ET-1 in renal arteries that is prevented by CR in 8m but not in 24m rats.

  9. Mild caloric restriction up-regulates the expression of prohibitin: A proteome study

    Energy Technology Data Exchange (ETDEWEB)

    Takahashi, Shoko; Masuda, Junko; Shimagami, Hiroshi [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Ohta, Yutaka; Kanda, Tomomasa [Research Laboratories for Health and Gustatory Science, Asahi Breweries Limited, Ibaraki (Japan); Saito, Kenji [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan); Kato, Hisanori, E-mail: akatoq@mail.ecc.u-tokyo.ac.jp [Department of Applied Biological Chemistry, The University of Tokyo, Tokyo (Japan); Corporate Sponsored Research Program ' Food for Life' , The University of Tokyo, Tokyo (Japan)

    2011-02-18

    Research highlights: {yields} Proteomic analysis was performed to elucidate physiological alterations induced by mild CR. {yields} The results suggest good reproducibility and possibility to grasp the important response of CR. {yields} The increase in prohibitin abundance was observed in CR groups by proteomic analysis. {yields} We hypothesize that prohibitin might be involved in the longevity induced by CR. -- Abstract: Caloric restriction (CR) is well known to expand lifespan in a variety of species and to retard many age-related diseases. The effects of relatively mild CR on the proteome profile in relation to lifespan have not yet been reported, despite the more extensive studies of the stricter CR conditions. Thus, the present study was conducted to elucidate the protein profiles in rat livers after mild CR for a relatively short time. Young growing rats were fed CR diets (10% and 30% CR) for 1 month. We performed the differential proteomic analysis of the rat livers using two-dimensional electrophoresis combined with MALDI-TOF mass spectrometry. The most remarkable protein among the differentially expressed proteins was found to be prohibitin, the abundance of which was increased by 30% CR. Prohibitin is a ubiquitously expressed protein shown to suppress cell proliferation and to be related to longevity. The increase in prohibitin was observed both in 10% and 30% CR by Western blot analysis. Furthermore, induction of AMP-activated kinase (AMPK) protein, related to the actions of prohibitin in promoting longevity, was observed. The increased prohibitin level in response to subtle CR suggests that this increase may be one of the early events leading to the expansion of lifespan in response to CR.

  10. Long-term intermittent feeding, but not caloric restriction, leads to redox imbalance, insulin receptor nitration, and glucose intolerance.

    Science.gov (United States)

    Cerqueira, Fernanda M; da Cunha, Fernanda M; Caldeira da Silva, Camille C; Chausse, Bruno; Romano, Renato L; Garcia, Camila C M; Colepicolo, Pio; Medeiros, Marisa H G; Kowaltowski, Alicia J

    2011-10-01

    Calorie restriction is a dietary intervention known to improve redox state, glucose tolerance, and animal life span. Other interventions have been adopted as study models for caloric restriction, including nonsupplemented food restriction and intermittent, every-other-day feedings. We compared the short- and long-term effects of these interventions to ad libitum protocols and found that, although all restricted diets decrease body weight, intermittent feeding did not decrease intra-abdominal adiposity. Short-term calorie restriction and intermittent feeding presented similar results relative to glucose tolerance. Surprisingly, long-term intermittent feeding promoted glucose intolerance, without a loss in insulin receptor phosphorylation. Intermittent feeding substantially increased insulin receptor nitration in both intra-abdominal adipose tissue and muscle, a modification associated with receptor inactivation. All restricted diets enhanced nitric oxide synthase levels in the insulin-responsive adipose tissue and skeletal muscle. However, whereas calorie restriction improved tissue redox state, food restriction and intermittent feedings did not. In fact, long-term intermittent feeding resulted in largely enhanced tissue release of oxidants. Overall, our results show that restricted diets are significantly different in their effects on glucose tolerance and redox state when adopted long-term. Furthermore, we show that intermittent feeding can lead to oxidative insulin receptor inactivation and glucose intolerance.

  11. Feed restriction and a diet's caloric value: The influence on the aerobic and anaerobic capacity of rats

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    de Moura Leandro

    2012-03-01

    Full Text Available Abstract Background The influence of feed restriction and different diet's caloric value on the aerobic and anaerobic capacity is unclear in the literature. Thus, the objectives of this study were to determine the possible influences of two diets with different caloric values and the influence of feed restriction on the aerobic (anaerobic threshold: AT and anaerobic (time to exhaustion: Tlim variables measured by a lactate minimum test (LM in rats. Methods We used 40 adult Wistar rats. The animals were divided into four groups: ad libitum commercial Purina® diet (3028.0 Kcal/kg (ALP, restricted commercial Purina® diet (RAP, ad libitum semi-purified AIN-93 diet (3802.7 Kcal/kg (ALD and restricted semi-purified AIN-93 diet (RAD. The animals performed LM at the end of the experiment, 48 h before euthanasia. Comparisons between groups were performed by analysis of variance (p Results At the end of the experiment, the weights of the rats in the groups with the restricted diets were significantly lower than those in the groups with ad libitum diet intakes. In addition, the ALD group had higher amounts of adipose tissue. With respect to energetic substrates, the groups subjected to diet restriction had significantly higher levels of liver and muscle glycogen. There were no differences between the groups with respect to AT; however, the ALD group had lower lactatemia at the AT intensity and higher Tlim than the other groups. Conclusions We conclude that dietary restriction induces changes in energetic substrates and that ad libitum intake of a semi-purified AIN-93 diet results in an increase in adipose tissue, likely reducing the density of the animals in water and favouring their performance during the swimming exercises.

  12. Formation of S-(carboxymethyl)-cysteine in rat liver mitochondrial proteins: effects of caloric and methionine restriction.

    Science.gov (United States)

    Naudí, Alba; Jové, Mariona; Cacabelos, Daniel; Ayala, Victoria; Cabre, Rosanna; Caro, Pilar; Gomez, José; Portero-Otín, Manuel; Barja, Gustavo; Pamplona, Reinald

    2013-02-01

    Maillard reaction contributes to the chemical modification and cross-linking of proteins. This process plays a significant role in the aging process and determination of animal longevity. Oxidative conditions promote the Maillard reaction. Mitochondria are the primary site of oxidants due to the reactive molecular species production. Mitochondrial proteome cysteine residues are targets of oxidative attack due to their specific chemistry and localization. Their chemical, non-enzymatic modification leads to dysfunctional proteins, which entail cellular senescence and organismal aging. Previous studies have consistently shown that caloric and methionine restrictions, nutritional interventions that increase longevity, decrease the rate of mitochondrial oxidant production and the physiological steady-state levels of markers of oxidative damage to macromolecules. In this scenario, we have detected S-(carboxymethyl)-cysteine (CMC) as a new irreversible chemical modification in mitochondrial proteins. CMC content in mitochondrial proteins significantly correlated with that of the lysine-derived analog N (ε)-(carboxymethyl)-lysine. The concentration of CMC is, however, one order of magnitude lower compared with CML likely due in part to the lower content of cysteine with respect to lysine of the mitochondrial proteome. CMC concentrations decreases in liver mitochondrial proteins of rats subjected to 8.5 and 25 % caloric restriction, as well as in 40 and 80 % methionine restriction. This is associated with a concomitant and significant increase in the protein content of sulfhydryl groups. Data presented here evidence that CMC, a marker of Cys-AGE formation, could be candidate as a biomarker of mitochondrial damage during aging.

  13. Time restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high fat diet

    OpenAIRE

    Hatori, Megumi; Vollmers, Christopher; Zarrinpar, Amir; DiTacchio, Luciano; Bushong, Eric A.; Gill, Shubhroz; Leblanc, Mathias; Chaix, Amandine; Joens, Matthew; Fitzpatrick, James A. J.; Ellisman, Mark H.; Panda, Satchidananda

    2012-01-01

    While diet-induced obesity has been exclusively attributed to increased caloric intake from fat, animals fed high fat diet (HFD) ad libitum (ad lib) eat frequently throughout day and night disrupting the normal feeding cycle. To test whether obesity and metabolic diseases result from HFD or disruption of metabolic cycles, we subjected mice to either ad lib or time restricted feeding (tRF) of a HFD for 8 h/day. Mice under tRF consume equivalent calories from HFD as those with ad lib access, ye...

  14. Chronic Caloric Restriction and Exercise Improve Metabolic Conditions of Dietary-Induced Obese Mice in Autophagy Correlated Manner without Involving AMPK

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    Mingxia Cui

    2013-01-01

    Full Text Available Aim. To investigate the role of AMPK activation and autophagy in mediating the beneficial effects of exercise and caloric restriction in obesity. Methods. Dietary-induced obesity mice were made and divided into 5 groups; one additional group of normal mice serves as control. Mice in each group received different combinations of interventions including low fat diet, caloric restriction, and exercise. Then their metabolic conditions were assessed by measuring serum glucose and insulin, serum lipids, and liver function. AMPK phosphorylation and autophagy activity were detected by western blotting. Results. Obese mice models were successfully induced by high fat diet. Caloric restriction consistently improved the metabolic conditions of the obese mice, and the effects are more prominent than the mice that received only exercise. Also, caloric restriction, exercise, and low fat diet showed a synergistic effect in the improvement of metabolic conditions. Western blotting results showed that this improvement was not related with the activation of AMPK in liver, skeletal muscle, or heart but correlates well with the autophagy activity. Conclusion. Caloric restriction has more prominent beneficial effects than exercise in dietary-induced obese mice. These effects are correlated with the autophagy activity and may be independent of AMPK activation.

  15. Effect of Resveratrol as Caloric Restriction Mimetic and Environmental Enrichment on Neurobehavioural Responses in Young Healthy Mice

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    Mustapha Shehu Muhammad

    2014-01-01

    Full Text Available Caloric restriction and environmental enrichment have been separately reported to possess health benefits such as improvement in motor and cognitive functions. Resveratrol, a natural polyphenolic compound, has been reported to be caloric restriction mimetic. This study therefore aims to investigate the potential benefit of the combination of resveratrol as CR and EE on learning and memory, motor coordination, and motor endurance in young healthy mice. Fifty mice of both sexes were randomly divided into five groups of 10 animals each: group I animals received carboxymethylcellulose (CMC orally per kg/day (control, group II animals were maintained on every other day feeding, group III animals received resveratrol 50 mg/kg, suspended in 10 g/L of (CMC orally per kg/day, group IV animals received CMC and were kept in an enriched environment, and group V animals received resveratrol 50 mg/kg and were kept in EE. The treatment lasted for four weeks. On days 26, 27, and 28 of the study period, the animals were subjected to neurobehavioural evaluation. The results obtained showed that there was no significant change (P>0.05 in neurobehavioural responses in all the groups when compared to the control which indicates that 50 mg/kg of resveratrol administration and EE have no significant effects on neurobehavioural responses in young healthy mice over a period of four weeks.

  16. Roles of caloric restriction, ketogenic diet and intermittent fasting during initiation, progression and metastasis of cancer in animal models: a systematic review and meta-analysis.

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    Mengmeng Lv

    Full Text Available The role of dietary restriction regimens such as caloric restriction, ketogenic diet and intermittent fasting in development of cancers has been detected via abundant preclinical experiments. However, the conclusions are controversial. We aim to review the relevant animal studies systematically and provide assistance for further clinical studies.Literatures on associations between dietary restriction and cancer published in PubMed in recent twenty years were comprehensively searched. Animal model, tumor type, feeding regimen, study length, sample size, major outcome, conclusion, quality assessment score and the interferential step of cancer were extracted from each eligible study. We analyzed the tumor incidence rates from 21 studies about caloric restriction.Fifty-nine studies were involved in our system review. The involved studies explored roles of dietary restriction during initiation, progression and metastasis of cancer. About 90.9% of the relevant studies showed that caloric restriction plays an anti-cancer role, with the pooled OR (95%CI of 0.20 (0.12, 0.34 relative to controls. Ketogenic diet was also positively associated with cancer, which was indicated by eight of the nine studies. However, 37.5% of the related studies obtained a negative conclusion that intermittent fasting was not significantly preventive against cancer.Caloric restriction and ketogenic diet are effective against cancer in animal experiments while the role of intermittent fasting is doubtful and still needs exploration. More clinical experiments are needed and more suitable patterns for humans should be investigated.

  17. Effects of 12 weeks of combined training without caloric restriction on inflammatory markers in overweight girls.

    Science.gov (United States)

    Lopes, Wendell Arthur; Leite, Neiva; da Silva, Larissa Rosa; Brunelli, Diego Trevisan; Gáspari, Arthur Fernandes; Radominski, Rosana Bento; Chacon-Mikahil, Mara Patrícia Traina; Cavaglieri, Cláudia Regina

    2016-10-01

    The objective of the present study was to investigate the effects of combined training without caloric restriction on inflammatory markers in overweight girls. Thirty-three girls (13-17 years) were assigned into overweight training (n = 17) or overweight control (n = 16) groups. Additionally, a normal-weight group (n = 15) was used as control for the baseline values. The combined training programme consisted of six resistance exercises (three sets of 6-10 repetitions at 60-70% 1 RM) followed by 30 min of aerobic exercise (walking/running) at 50-80% VO2peak, performed in the same 60 min session, 3 days/weeks, for 12 weeks. Body composition, dietary intake, aerobic fitness (VO2peak), muscular strength (1 RM), glycaemia, insulinemia, lipid profile and inflammatory markers (C-reactive protein, interleukin-6, tumour necrosis factor-alpha, interleukin-10, leptin, resistin and adiponectin) were measured before and after intervention. There was a significant decrease in body fat (P < 0.01) and increase in fat-free mass (P < 0.01), VO2peak (P < 0.01), 1 RM for leg press (P < 0.01) and bench press (P < 0.01) in the overweight training group. Concomitantly, this group presented significant decreases in serum concentrations of C-reactive protein (P < 0.05) and leptin (P < 0.05), as well as in insulin resistance (P < 0.05) after the experimental period. In conclusion, 12 weeks of combined training without caloric restriction reduced inflammatory markers associated with obesity in overweight girls.

  18. Effects of aerobic versus resistance exercise without caloric restriction on abdominal fat, intrahepatic lipid, and insulin sensitivity in obese adolescent boys: a randomized, controlled trial

    Science.gov (United States)

    The optimal exercise modality for reductions of abdominal obesity and risk factors for type 2 diabetes in youth is unknown. We examined the effects of aerobic exercise (AE) versus resistance exercise (RE) without caloric restriction on abdominal adiposity, ectopic fat, and insulin sensitivity and se...

  19. Caloric Restriction reduces inflammation and improves T cell-mediated immune response in obese mice but concomitant consumption of curcumin/piperine adds no further benefit

    Science.gov (United States)

    Obesity is associated with low-grade inflammation and impaired immune response. Caloric restriction (CR) has been shown to inhibit inflammatory response and enhance cell-mediated immune function. Curcumin, the bioactive phenolic component of turmeric spice, is proposed to have anti-obesity and anti-...

  20. Caloric restriction restores the chronological life span of the Goa1 null mutant of Candida albicans in spite of high cell levels of ROS.

    Science.gov (United States)

    Chen, Hui; Calderone, Richard; Sun, Nuo; Wang, Yun; Li, Dongmei

    2012-12-01

    The Candida albicans Goa1p is required for mitochondrial functions. In a strain lacking GOA1 (GOA31), respiration, mitochondrial membrane potential, complex I (CI) activity of the electron transport chain, and ATP synthesis are significantly decreased. A shortened chronological life span (CLS) of GOA31 occurs in 2% glucose that is associated with an increase in cell reactive oxidant species (ROS) and apoptosis. We now show that caloric restriction (CR) in media containing 0.5% glucose instead of 2% glucose-SC extends the CLS to the level of parental and gene-reconstituted strains. Paradoxically, ROS levels in GOA31 far exceed those of control strains in 0.5% glucose and, as a consequence, increased lipid peroxidation occurs even though CLS is restored. Microarray analysis was used to characterize transcriptional changes during CR in GOA31. We found that CR shifts cells of all strains to a non-glucose carbon metabolism (β-oxidation). Our model of ROS formation in GOA31 follows the paradigm that the generation of oxygen radicals from β-oxidation of cell lipids via FADH(2) (CII) and NADH (CI) creates an unfavorable cellular FADH(2)/NADH ratio that causes a transient overload in CII activity resulting in excess free cell radicals. In GOA31 the CI and peroxisomal dysfunctions increase the levels of ROS compared to control strains. Recovery from high levels of ROS may be associated with an increase in iron and sugar transporters, as well as an anti-stress response that includes the SOD1 and GPX1. Thus, CR creates a favorable growth environment, but cells of GOA31 must overcome a high but transient ROS production.

  1. Glycemic effects of intensive caloric restriction and isocaloric refeeding in noninsulin-dependent diabetes mellitus.

    Science.gov (United States)

    Henry, R R; Scheaffer, L; Olefsky, J M

    1985-11-01

    To assess the effects of very low caloric (VLC) diets on glucose homeostasis in noninsulin-dependent diabetes mellitus, 30 obese subjects with NIDDM were studied for 40 days while eating a 330 Cal/day diet, with a subgroup of 12 subjects further evaluated during 40 days of refeeding. All subjects successfully lost weight, with an average weight loss of 4.6 +/- 0.2 kg (+/- SEM) after 10 days, 7.1 +/- 0.3 kg after 20 days, and 10.5 +/- 0.4 kg after 40 days of VLC diet therapy. Thus, weight loss was steady and progressive throughout the diet period. In contrast, the majority (87%) of the reduction in mean fasting plasma glucose (FPG) levels (297 +/- 13 to 158 +/- 10 mg/dl; P less than 0.001) occurred after 10 days of VLC diet therapy, with a further reduction in glucose levels to 138 +/- 9 mg/dl on day 40. The FPG response measured after 10 days of VLC diet was unrelated to the degree of obesity, rate or extent of weight loss, or prevailing insulin levels, but did correlate significantly with the initial FPG level (r = 0.37; P less than 0.05) and duration of diabetes (r = 0.42; P less than 0.05). After discontinuation of the VLC diet and refeeding of an isocaloric (weight maintenance) diet in 12 subjects, a variable increase in the FPG occurred, with an average increase of 80% after 40 days of refeeding. However, the mean FPG level after 40 days of refeeding was still markedly lower than that before VLC diet therapy (254 +/- 20 vs. 167 +/- 14 mg/dl; P less than 0.02) despite withdrawal of antidiabetic medication in all subjects. The basal hepatic glucose output (HGO) fell rapidly from 149 +/- 13 to 81 +/- 5 mg/M2 X min (P less than 0.001) after 10 days of VLC diet and rose from 67 +/- 4 to 88 +/- 7 mg/M2 X min (P less than 0.001) after 10 days of refeeding. Basal HGO demonstrated a highly significant positive correlation with FPG levels (r = 0.89; P less than 0.001) before and during both VLC diet therapy and refeeding. A significant correlation was also found between

  2. Reducing Liver Fat by Low Carbohydrate Caloric Restriction Targets Hepatic Glucose Production in Non-Diabetic Obese Adults with Non-Alcoholic Fatty Liver Disease

    Science.gov (United States)

    Yu, Haoyong; Jia, Weiping; Guo, ZengKui

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) impairs liver functions, the organ responsible for the regulation of endogenous glucose production and thus plays a key role in glycemic homeostasis. Therefore, interventions designed to normalize liver fat content are needed to improve glucose metabolism in patients affected by NAFLD such as obesity. Objective: this investigation is designed to determine the effects of caloric restriction on hepatic and peripheral glucose metabolism in obese humans with NAFLD. Methods: eight non-diabetic obese adults were restricted for daily energy intake (800 kcal) and low carbohydrate ( 0.05). Liver fat is the only independent variable highly correlated to HGP after the removal of confounders. Conclusion: NAFLD impairs HGP but not peripheral glucose disposal; low carbohydrate caloric restriction effectively lowers liver fat which appears to directly correct the HGP impairment. PMID:25411646

  3. Cardiac Sirt1 mediates the cardioprotective effect of caloric restriction by suppressing local complement system activation after ischemia-reperfusion.

    Science.gov (United States)

    Yamamoto, Tsunehisa; Tamaki, Kayoko; Shirakawa, Kohsuke; Ito, Kentaro; Yan, Xiaoxiang; Katsumata, Yoshinori; Anzai, Atsushi; Matsuhashi, Tomohiro; Endo, Jin; Inaba, Takaaki; Tsubota, Kazuo; Sano, Motoaki; Fukuda, Keiichi; Shinmura, Ken

    2016-04-15

    Caloric restriction (CR) confers cardioprotection against ischemia-reperfusion (I/R) injury. We previously found the essential roles of endothelial nitric oxide synthase in the development of CR-induced cardioprotection and Sirt1 activation during CR (Shinmura K, Tamaki K, Ito K, Yan X, Yamamoto T, Katsumata Y, Matsuhashi T, Sano M, Fukuda K, Suematsu M, Ishii I. Indispensable role of endothelial nitric oxide synthase in caloric restriction-induced cardioprotection against ischemia-reperfusion injury.Am J Physiol Heart Circ Physiol 308: H894-H903, 2015). However, the exact mechanism by which Sirt1 in cardiomyocytes mediates the cardioprotective effect of CR remains undetermined. We subjected cardiomyocyte-specific Sirt1 knockout (CM-Sirt1(-/-)) mice and the corresponding control mice to either 3-mo ad libitum feeding or CR (-40%). Isolated perfused hearts were subjected to 25-min global ischemia, followed by 60-min reperfusion. The recovery of left ventricle function after I/R was improved, and total lactate dehydrogenase release into the perfusate during reperfusion was attenuated in the control mice treated with CR, but a similar cardioprotective effect of CR was not observed in the CM-Sirt1(-/-)mice. The expression levels of cardiac complement component 3 (C3) at baseline and the accumulation of C3 and its fragments in the ischemia-reperfused myocardium were attenuated by CR in the control mice, but not in the CM-Sirt1(-/-)mice. Resveratrol treatment also attenuated the expression levels of C3 protein in cultured neonatal rat ventricular cardiomyocytes. Moreover, the degree of myocardial I/R injury in conventional C3 knockout (C3(-/-)) mice treated with CR was similar to that in the ad libitum-fed C3(-/-)mice, although the expression levels of Sirt1 were enhanced by CR. These results demonstrate that cardiac Sirt1 plays an essential role in CR-induced cardioprotection against I/R injury by suppressing cardiac C3 expression. This is the first report suggesting

  4. Effects of Caloric Restriction and Exercise Training on Skeletal Muscle Histochemistry in Aging Fischer 344 Rats

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    David T. Lowenthal

    2006-01-01

    Full Text Available The purpose of this study was to determine the effects of calorie restriction and exercise on hindlimb histochemistry and fiber type in Fischer 344 rats as they advanced from adulthood through senescence. At 10 months of age, animals were divided into sedentary fed ad libitum, exercise (18 m/min, 8% grade, 20 min/day, 5 days/week fed ad libitum, and calorie restricted by alternate days of feeding. Succinic dehydrogenase, myosin adenosine triphosphatase (mATPase at pH 9.4, nicotine adenonine dinucleotide reductase, and Periodic Acid Shiff histochemical stains were performed on plantaris and soleus muscles. The results indicated that aging resulted in a progressive decline in plantaris Type I muscle fiber in sedentary animals, while exercise resulted in maintenance of these fibers. The percent of plantaris Type II fibers increased between 10 and 24 months of age. Exercise also resulted in a small, but significant, increase in the percentage of plantaris Type IIa fibers at 24 months of age. The soleus fiber distribution for Type I fibers was unaffected by increasing age in all groups of animals. The implications of these results suggest the implementation of exercise as a lifestyle modification as early as possible.

  5. Caloric restriction, resveratrol and melatonin: Role of SIRT1 and implications for aging and related-diseases.

    Science.gov (United States)

    Ramis, Margarita R; Esteban, Susana; Miralles, Antonio; Tan, Dun-Xian; Reiter, Russel J

    2015-03-01

    Aging is an inevitable and multifactorial biological process. Free radicals have been implicated in aging processes; it is hypothesized that they cause cumulative oxidative damage to crucial macromolecules and are responsible for failure of multiple physiological mechanisms. However, recent investigations have also suggested that free radicals can act as modulators of several signaling pathways such as those related to sirtuins. Caloric restriction is a non-genetic manipulation that extends lifespan of several species and improves healthspan; the belief that many of these benefits are due to the induction of sirtuins has led to the search for sirtuin activators, especially sirtuin 1, the most studied. Resveratrol, a polyphenol found in red grapes, was first known for its antioxidant and antifungal properties, and subsequently has been reported several biological effects, including the activation of sirtuins. Endogenously-produced melatonin, a powerful free radical scavenger, declines with age and its loss contributes to degenerative conditions of aging. Recently, it was reported that melatonin also activates sirtuins, in addition to other functions, such as regulator of circadian rhythms or anti-inflammatory properties. The fact that melatonin and resveratrol are present in various foods, exhibiting possible synergistic effects, suggests the use of dietary ingredients to promote health and longevity.

  6. mTOR and autophagy in normal brain aging and caloric restriction ameliorating age-related cognition deficits.

    Science.gov (United States)

    Yang, Fengying; Chu, Xiaolei; Yin, Miaomiao; Liu, Xiaolei; Yuan, Hairui; Niu, Yanmei; Fu, Li

    2014-05-01

    Defect of autophagy is common to many neurodegenerative disorders because it serves as a major degradation pathway for the clearance of various aggregate-prone proteins. Mammalian target of rapamycin (mTOR) signaling, which is recognized as the most important negative regulator of autophagy, is also involved in neurodegenerative diseases. However, the role of mTOR and its dependent autophagy in normal brain during aging remains unknown. Furthermore, caloric restriction (CR) is frequently used as a tool to study mechanisms behind aging and age-associated diseases because CR can prevent age-related diseases and prolong lifespan in several model organisms. Inhibiting mTOR and promoting autophagy activity play roles in aging delayed by CR. However, whether CR can ameliorate age-related cognition deficits by inhibiting mTOR and activate autophagy in hippocampus needs to be further investigated. Here we showed a decline of autophagic degradation in mice hippocampus in correlation with age-dependent cognitive dysfunction, whereas the activity of mTOR and its upstream brain-derived neurotrophic factor (BDNF)/phosphatidylinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling was decreased with aging. In addition, facilitating the mTOR pathway successfully declines and sustains autophagic degradation with aging in hippocampus by CR treatment and is involved in CR by ameliorating age-related cognitive deficits.

  7. Caloric restriction increases internal iliac artery and penil nitric oxide synthase expression in rat: Comparison of aged and adult rats

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    Emin Ozbek

    2013-09-01

    Full Text Available Because of the positive corelation between healthy cardiovascular system and sexual life we aimed to evaluate the effect of caloric restriction (CR on endothelial and neuronal nitric oxide synthase (eNOS, nNOS expression in cavernousal tissues and eNOS expression in the internal iliac artery in young and aged rats. Young (3 mo, n = 7 and aged (24 mo, n = 7 male Sprague-Dawley rats were subjected to 40% CR and were allowed free access to water for 3 months. Control rats (n = 14 fed ad libitum had free access to food and water at all times. On day 90, rats were sacrified and internal iliac arteries and penis were removed and parafinized, eNOS and nNOS expression evaluated with immunohistochemistry. Results were evaluated semiquantitatively. eNOS and nNOS expression in cavernousal tis- sue in CR rats were more strong than in control group in both young and old rats. eNOS expression was also higher in the internal iliac arteries of CR rats than in control in young and old rats. As a result of our study we can say that there is a positive link between CR and neurotransmitter of erection in cavernousal tissues and internal iliac arteries. CR has beneficial effect to prevent sexual dysfunction in young and old animals and possible humans.

  8. Time-restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high-fat diet.

    Science.gov (United States)

    Hatori, Megumi; Vollmers, Christopher; Zarrinpar, Amir; DiTacchio, Luciano; Bushong, Eric A; Gill, Shubhroz; Leblanc, Mathias; Chaix, Amandine; Joens, Matthew; Fitzpatrick, James A J; Ellisman, Mark H; Panda, Satchidananda

    2012-06-06

    While diet-induced obesity has been exclusively attributed to increased caloric intake from fat, animals fed a high-fat diet (HFD) ad libitum (ad lib) eat frequently throughout day and night, disrupting the normal feeding cycle. To test whether obesity and metabolic diseases result from HFD or disruption of metabolic cycles, we subjected mice to either ad lib or time-restricted feeding (tRF) of a HFD for 8 hr per day. Mice under tRF consume equivalent calories from HFD as those with ad lib access yet are protected against obesity, hyperinsulinemia, hepatic steatosis, and inflammation and have improved motor coordination. The tRF regimen improved CREB, mTOR, and AMPK pathway function and oscillations of the circadian clock and their target genes' expression. These changes in catabolic and anabolic pathways altered liver metabolome and improved nutrient utilization and energy expenditure. We demonstrate in mice that tRF regimen is a nonpharmacological strategy against obesity and associated diseases.

  9. Caloric Restriction Is More Efficient than Physical Exercise to Protect from Cisplatin Nephrotoxicity via PPAR-Alpha Activation

    Science.gov (United States)

    Estrela, Gabriel R.; Wasinski, Frederick; Batista, Rogério O.; Hiyane, Meire I.; Felizardo, Raphael J. F.; Cunha, Flavia; de Almeida, Danilo C.; Malheiros, Denise M. A. C.; Câmara, Niels O. S.; Barros, Carlos C.; Bader, Michael; Araujo, Ronaldo C.

    2017-01-01

    The antineoplastic drug cisplatin promotes renal injury, which limits its use. Protocols that reduce renal cisplatin toxicity will allow higher doses to be used in cisplatin treatment. Here, we compare physical exercise and caloric restriction (CR) as protocols to reduce cisplatin renal injury in mice. Male C57BL/6 were divided into four groups: Control, cisplatin, exercise + cisplatin, and 30% CR + cisplatin. Animals were injected with a single dose of cisplatin (20 mg/kg i.p.) and sacrificed 96 h after injection. Quantitative real time PCR, histological analyses, immunohistochemistry, and biochemical measurements were performed to investigate renal injury, necrosis, apoptosis, and inflammatory mechanisms. Both protocols protected against cisplatin renal injury, but CR was more effective in reducing uraemia and renal necrosis. The CR + Cisplatin group exhibited reduced serum IL-1β and TNF-α levels. No differences were noted in the renal mRNA expression of cytokines. Both interventions reduced apoptosis, but only the CR + Cisplatin group decreased TNFR2 protein expression. PPAR-α was activated in mice after CR. An antagonist of PPAR-α blocked the protective effect of CR. Both interventions attenuated the nephrotoxicity caused by cisplatin injection, but CR + Cisplatin showed a better response by modulating TNFR2. Moreover, part of the CR benefit depends on PPAR-α activation. PMID:28303105

  10. A meta-analysis of caloric restriction gene expression profiles to infer common signatures and regulatory mechanisms.

    Science.gov (United States)

    Plank, Michael; Wuttke, Daniel; van Dam, Sipko; Clarke, Susan A; de Magalhães, João Pedro

    2012-04-01

    Caloric restriction, a reduction in calorie intake without malnutrition, retards age-related degeneration and extends lifespan in several organisms. CR induces multiple changes, yet its underlying mechanisms remain poorly understood. In this work, we first performed a meta-analysis of microarray CR studies in mammals and identified genes and processes robustly altered due to CR. Our results reveal a complex array of CR-induced changes and we re-identified several genes and processes previously associated with CR, such as growth hormone signalling, lipid metabolism and immune response. Moreover, our results highlight novel associations with CR, such as retinol metabolism and copper ion detoxification, as well as hint of a strong effect of CR on circadian rhythms that in turn may contribute to metabolic changes. Analyses of our signatures by integrating co-expression data, information on genetic mutants, and transcription factor binding site analysis revealed candidate regulators of transcriptional modules in CR. Our results hint at a transcriptional module involved in sterol metabolism regulated by Srebf1. A putative regulatory role of Ppara was also identified. Overall, our conserved molecular signatures of CR provide a comprehensive picture of CR-induced changes and help understand its regulatory mechanisms.

  11. Caloric Restriction and the Nutrient-Sensing PGC-1α in Mitochondrial Homeostasis: New Perspectives in Neurodegeneration

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    Daniele Lettieri Barbato

    2012-01-01

    Full Text Available Mitochondrial activity progressively declines during ageing and in many neurodegenerative diseases. Caloric restriction (CR has been suggested as a dietary intervention that is able to postpone the detrimental aspects of aging as it ameliorates mitochondrial performance. This effect is partially due to increased mitochondrial biogenesis. The nutrient-sensing PGC-1α is a transcriptional coactivator that promotes the expression of mitochondrial genes and is induced by CR. It is believed that many of the mitochondrial and metabolic benefits of CR are due to increased PGC-1α activity. The increase of PGC-1α is also positively linked to neuroprotection and its decrement has been involved in the pathogenesis of many neurodegenerative diseases. This paper aims to summarize the current knowledge about the role of PGC-1α in neuronal homeostasis and the beneficial effects of CR on mitochondrial biogenesis and function. We also discuss how PGC-1α-governed pathways could be used as target for nutritional intervention to prevent neurodegeneration.

  12. Time restricted feeding without reducing caloric intake prevents metabolic diseases in mice fed a high fat diet

    Science.gov (United States)

    Hatori, Megumi; Vollmers, Christopher; Zarrinpar, Amir; DiTacchio, Luciano; Bushong, Eric A.; Gill, Shubhroz; Leblanc, Mathias; Chaix, Amandine; Joens, Matthew; Fitzpatrick, James A. J.; Ellisman, Mark H.; Panda, Satchidananda

    2012-01-01

    SUMMARY While diet-induced obesity has been exclusively attributed to increased caloric intake from fat, animals fed high fat diet (HFD) ad libitum (ad lib) eat frequently throughout day and night disrupting the normal feeding cycle. To test whether obesity and metabolic diseases result from HFD or disruption of metabolic cycles, we subjected mice to either ad lib or time restricted feeding (tRF) of a HFD for 8 h/day. Mice under tRF consume equivalent calories from HFD as those with ad lib access, yet are protected against obesity, hyperinsulinemia, hepatic steatosis, inflammation, and have improved motor coordination. The tRF regimen improved CREB, mTOR and AMPK pathway function and oscillations of the circadian clock and their target genes' expression. These changes in catabolic and anabolic pathways altered liver metabolome, improved nutrient utilization and energy expenditure. We demonstrate in mice that tRF regimen is a non-pharmacological strategy against obesity and associated diseases. PMID:22608008

  13. Caloric restriction protects against electrical kindling of the amygdala by inhibiting the mTOR signaling pathway.

    Science.gov (United States)

    Phillips-Farfán, Bryan V; Rubio Osornio, María Del Carmen; Custodio Ramírez, Verónica; Paz Tres, Carlos; Carvajal Aguilera, Karla G

    2015-01-01

    Caloric restriction (CR) has been shown to possess antiepileptic properties; however its mechanism of action is poorly understood. CR might inhibit the activity of the mammalian or mechanistic target of rapamycin (mTOR) signaling cascade, which seems to participate crucially in the generation of epilepsy. Thus, we investigated the effect of CR on the mTOR pathway and whether CR modified epilepsy generation due to electrical amygdala kindling. The former was studied by analyzing the phosphorylation of adenosine monophosphate-activated protein kinase, protein kinase B and the ribosomal protein S6. The mTOR cascade is regulated by energy and by insulin levels, both of which may be changed by CR; thus we investigated if CR altered the levels of energy substrates in the blood or the level of insulin in plasma. Finally, we studied if CR modified the expression of genes that encode proteins participating in the mTOR pathway. CR increased the after-discharge threshold and tended to reduce the after-discharge duration, indicating an anti-convulsive action. CR diminished the phosphorylation of protein kinase B and ribosomal protein S6, suggesting an inhibition of the mTOR cascade. However, CR did not change glucose, β-hydroxybutyrate or insulin levels; thus the effects of CR were independent from them. Interestingly, CR also did not modify the expression of any investigated gene. The results suggest that the anti-epileptic effect of CR may be partly due to inhibition of the mTOR pathway.

  14. Reducing Liver Fat by Low Carbohydrate Caloric Restriction Targets Hepatic Glucose Production in Non-Diabetic Obese Adults with Non-Alcoholic Fatty Liver Disease

    Directory of Open Access Journals (Sweden)

    Haoyong Yu

    2014-09-01

    Full Text Available Non-alcoholic fatty liver disease (NAFLD impairs liver functions, the organ responsible for the regulation of endogenous glucose production and thus plays a key role in glycemic homeostasis. Therefore, interventions designed to normalize liver fat content are needed to improve glucose metabolism in patients affected by NAFLD such as obesity. Objective: this investigation is designed to determine the effects of caloric restriction on hepatic and peripheral glucose metabolism in obese humans with NAFLD. Methods: eight non-diabetic obese adults were restricted for daily energy intake (800 kcal and low carbohydrate (<10% for 8 weeks. Body compositions, liver fat and hepatic glucose production (HGP and peripheral glucose disposal before and after the intervention were determined. Results: the caloric restriction reduced liver fat content by 2/3 (p = 0.004. Abdominal subcutaneous and visceral fat, body weight, BMI, waist circumference and fasting plasma triglyceride and free fatty acid concentrations all significantly decreased (p < 0.05. The suppression of post-load HGP was improved by 22% (p = 0.002 whereas glucose disposal was not affected (p = 0.3. Fasting glucose remained unchanged and the changes in the 2-hour plasma glucose and insulin concentration were modest and statistically insignificant (p > 0.05. Liver fat is the only independent variable highly correlated to HGP after the removal of confounders. Conclusion: NAFLD impairs HGP but not peripheral glucose disposal; low carbohydrate caloric restriction effectively lowers liver fat which appears to directly correct the HGP impairment.

  15. 限食疗法与体重控制%Caloric restriction and control of body weight

    Institute of Scientific and Technical Information of China (English)

    陈国芳; 刘超

    2014-01-01

    控制体重一直是热门话题,减重所带来的血糖、血脂、血压、胰岛素敏感性等多方面的获益,奠定了其在防治肥胖、2型糖尿病等代谢性疾病中的不可撼动的地位.获得减重的途径主要有饮食调整、运动干预、药物治疗或外科手术,本文主要讨论限食减重的问题,包括限食的减重程度,限食后的体重维持,影响减重的因素以及特殊人群的减重问题.%Control of body weight is a hot topic.It is considered as the cornerstone for the management of patients with obesity and type 2 diabetes based on the effect of improving blood glucose,lipid profile,blood pressure,and insulin sensitivity.The strategies for weight loss include diet restriction,exercise,medicine,and bariatric surgery.In the present article the relationship between caloric restriction and weight loss was reviewed,focusing on the hot topics as to what extent weight loss could be achieved,the maintenance of ideal body weight,the risk factor of weight regain,and weight loss in particulas populations like obese children,adolescents,and older adults.

  16. A low dose of dietary resveratrol partially mimics caloric restriction and retards aging parameters in mice.

    Science.gov (United States)

    Barger, Jamie L; Kayo, Tsuyoshi; Vann, James M; Arias, Edward B; Wang, Jelai; Hacker, Timothy A; Wang, Ying; Raederstorff, Daniel; Morrow, Jason D; Leeuwenburgh, Christiaan; Allison, David B; Saupe, Kurt W; Cartee, Gregory D; Weindruch, Richard; Prolla, Tomas A

    2008-06-04

    Resveratrol in high doses has been shown to extend lifespan in some studies in invertebrates and to prevent early mortality in mice fed a high-fat diet. We fed mice from middle age (14-months) to old age (30-months) either a control diet, a low dose of resveratrol (4.9 mg kg(-1) day(-1)), or a calorie restricted (CR) diet and examined genome-wide transcriptional profiles. We report a striking transcriptional overlap of CR and resveratrol in heart, skeletal muscle and brain. Both dietary interventions inhibit gene expression profiles associated with cardiac and skeletal muscle aging, and prevent age-related cardiac dysfunction. Dietary resveratrol also mimics the effects of CR in insulin mediated glucose uptake in muscle. Gene expression profiling suggests that both CR and resveratrol may retard some aspects of aging through alterations in chromatin structure and transcription. Resveratrol, at doses that can be readily achieved in humans, fulfills the definition of a dietary compound that mimics some aspects of CR.

  17. Reducing Liver Fat by Low Carbohydrate Caloric Restriction Targets Hepatic Glucose Production in Non-Diabetic Obese Adults with Non-Alcoholic Fatty Liver Disease

    OpenAIRE

    Haoyong Yu; Weiping Jia; ZengKui Guo

    2014-01-01

    Non-alcoholic fatty liver disease (NAFLD) impairs liver functions, the organ responsible for the regulation of endogenous glucose production and thus plays a key role in glycemic homeostasis. Therefore, interventions designed to normalize liver fat content are needed to improve glucose metabolism in patients affected by NAFLD such as obesity. Objective: this investigation is designed to determine the effects of caloric restriction on hepatic and peripheral glucose metabolism in obese humans w...

  18. Areal and Volumetric Bone Mineral Density and Geometry at Two Levels of Protein Intake During Caloric Restriction: A Randomized, Controlled Trial

    OpenAIRE

    Sukumar, Deeptha; Ambia-Sobhan, Hasina; Zurfluh, Robert; Schlussel, Yvette; Stahl, Theodore J; Gordon, Chris L; SHAPSES, SUE A.

    2010-01-01

    Weight reduction induces bone loss by several factors, and the effect of higher protein (HP) intake during caloric restriction on bone mineral density (BMD) is not known. Previous study designs examining the longer-term effects of HP diets have not controlled for total calcium intake between groups and have not examined the relationship between bone and endocrine changes. In this randomized, controlled study, we examined how BMD (areal and volumetric), turnover markers, and hormones [insulin-...

  19. Caloric restriction induces energy-sparing alterations in skeletal muscle contraction, fiber composition and local thyroid hormone metabolism that persist during catch-up fat upon refeeding

    Directory of Open Access Journals (Sweden)

    Paula Bresciani M. De Andrade

    2015-09-01

    Full Text Available Weight regain after caloric restriction results in accelerated fat storage in adipose tissue. This catch-up fat phenomenon is postulated to result partly from suppressed skeletal muscle thermogenesis, but the underlying mechanisms are elusive. We investigated whether the reduced rate of skeletal muscle contraction-relaxation cycle that occurs after caloric restriction persists during weight recovery and could contribute to catch-up fat. Using a rat model of semistarvation-refeeding, in which fat recovery is driven by suppressed thermogenesis, we show that contraction and relaxation of leg muscles are slower after both semistarvation and refeeding. These effects are associated with (i higher expression of muscle deiodinase type 3 (DIO3 which inactivates tri-iodothyronine (T3, and lower expression of T3-activating enzyme, deiodinase type 2 (DIO2, (ii slower net formation of T3 from its T4 precursor in muscles, and (iii accumulation of slow fibers at the expense of fast fibers. These semistarvation-induced changes persisted during recovery and correlated with impaired expression of transcription factors involved in slow-twitch muscle development.We conclude that diminished muscle thermogenesis following caloric restriction results from reduced muscle T3 levels, alteration in muscle-specific transcription factors, and fast-to-slow fiber shift causing slower contractility. Energy-sparing effects persist during weight recovery and likely contribute to catch-up fat.

  20. Caloric restriction alters the metabolic response to a mixed-meal: results from a randomized, controlled trial.

    Directory of Open Access Journals (Sweden)

    Kim M Huffman

    Full Text Available OBJECTIVES: To determine if caloric restriction (CR would cause changes in plasma metabolic intermediates in response to a mixed meal, suggestive of changes in the capacity to adapt fuel oxidation to fuel availability or metabolic flexibility, and to determine how any such changes relate to insulin sensitivity (S(I. METHODS: Forty-six volunteers were randomized to a weight maintenance diet (Control, 25% CR, or 12.5% CR plus 12.5% energy deficit from structured aerobic exercise (CR+EX, or a liquid calorie diet (890 kcal/d until 15% reduction in body weightfor six months. Fasting and postprandial plasma samples were obtained at baseline, three, and six months. A targeted mass spectrometry-based platform was used to measure concentrations of individual free fatty acids (FFA, amino acids (AA, and acylcarnitines (AC. S(I was measured with an intravenous glucose tolerance test. RESULTS: Over three and six months, there were significantly larger differences in fasting-to-postprandial (FPP concentrations of medium and long chain AC (byproducts of FA oxidation in the CR relative to Control and a tendency for the same in CR+EX (CR-3 month P = 0.02; CR-6 month P = 0.002; CR+EX-3 month P = 0.09; CR+EX-6 month P = 0.08. After three months of CR, there was a trend towards a larger difference in FPP FFA concentrations (P = 0.07; CR-3 month P = 0.08. Time-varying differences in FPP concentrations of AC and AA were independently related to time-varying S(I (P<0.05 for both. CONCLUSIONS: Based on changes in intermediates of FA oxidation following a food challenge, CR imparted improvements in metabolic flexibility that correlated with improvements in S(I. TRIAL REGISTRATION: ClinicalTrials.gov NCT00099151.

  1. Caloric restriction protects against electrical kindling of the amygdala by inhibiting the mTOR signaling pathway

    Directory of Open Access Journals (Sweden)

    Bryan Victor Phillips-Farfan

    2015-03-01

    Full Text Available Caloric restriction (CR has been shown to possess antiepileptic properties; however its mechanism of action is poorly understood. CR might inhibit the activity of the mammalian or mechanistic target of rapamycin (mTOR signaling cascade, which seems to participate crucially in the generation of epilepsy. Thus, we investigated the effect of CR on the mTOR pathway and whether CR modified epilepsy generation due to electrical amygdala kindling. The former was studied by analyzing the phosphorylation of adenosine monophosphate-activated protein kinase, protein kinase B and the ribosomal protein S6. The mTOR cascade is regulated by energy and by insulin levels, both of which may be changed by CR; thus we investigated if CR altered the levels of energy substrates in the blood or the level of insulin in plasma. Finally, we studied if CR modified the expression of genes that encode proteins participating in the mTOR pathway. CR increased the after-discharge threshold and tended to reduce the after-discharge duration, indicating an anti-convulsive action. CR diminished the phosphorylation of protein kinase B and ribosomal protein S6, suggesting an inhibition of the mTOR cascade. However, CR did not change glucose, β-hydroxybutyrate or insulin levels; thus the effects of CR were independent from them. Interestingly, CR also did not modify the expression of any investigated gene. The results suggest that the anti-epileptic effect of CR may be partly due to inhibition of the mTOR pathway.

  2. The effects of exercise training and caloric restriction on the cardiac oxytocin natriuretic peptide system in the diabetic mouse

    Science.gov (United States)

    Broderick, Tom L; Jankowski, Marek; Gutkowska, Jolanta

    2017-01-01

    Background Regular exercise training (ET) and caloric restriction (CR) are the frontline strategies in the treatment of type 2 diabetes mellitus with the aim at reducing cardiometabolic risk. ET and CR improve body weight and glycemic control, and experimental studies indicate that these paradigms afford cardioprotection. In this study, the effects of combined ET and CR on the cardioprotective oxytocin (OT)–natriuretic peptide (NP) system were determined in the db/db mouse, a model of type 2 diabetes associated with insulin resistance, hyperglycemia, and obesity. Methods Five-week-old male db/db mice were assigned to the following groups: sedentary, ET, and ET + CR. Nonobese heterozygote littermates served as controls. ET was performed on a treadmill at moderate intensity, and CR was induced by reducing food intake by 30% of that consumed by sedentary db/db mice for a period of 8 weeks. Results After 8 weeks, only ET + CR, but not ET, slightly improved body weight compared to sedentary db/db mice. Regardless of the treatment, db/db mice remained hyperglycemic. Hearts from db/db mice demonstrated reduced expression of genes linked to the cardiac OT–NP system. In fact, compared to control mice, mRNA expression of GATA binding protein 4 (GATA4), OT receptor, OT, brain NP, NP receptor type C, and endothelial nitric oxide synthase (eNOS) was decreased in hearts from sedentary db/db mice. Both ET alone and ET + CR increased the mRNA expression of GATA4 compared to sedentary db/db mice. Only ET combined with CR produced increased eNOS mRNA and protein expression. Conclusion Our data indicate that enhancement of eNOS by combined ET and CR may improve coronary endothelial vasodilator dysfunction in type 2 diabetes but did not prevent the downregulation of cardiac expression in the OT–NP system, possibly resulting from the sustained hyperglycemia and obesity in diabetic mice. PMID:28138261

  3. Caloric restriction extends yeast chronological lifespan by altering a pattern of age-related changes in trehalose concentration

    Directory of Open Access Journals (Sweden)

    Pavlo eKyryakov

    2012-07-01

    Full Text Available The nonreducing disaccharide trehalose has been long considered only as a reserve carbohydrate. However, recent studies in yeast suggested that this osmolyte can protect cells and cellular proteins from oxidative damage elicited by exogenously added reactive oxygen species (ROS. Trehalose has been also shown to affect stability, folding and aggregation of bacterial and firefly proteins heterologously expressed in heat-shocked yeast cells. Our recent investigation of how a lifespan-extending caloric restriction (CR diet alters the metabolic history of chronologically aging yeast suggested that their longevity is programmed by the level of metabolic capacity - including trehalose biosynthesis and degradation - that yeast cells developed prior to entry into quiescence. To investigate whether trehalose homeostasis in chronologically aging yeast may play a role in longevity extension by CR, in this study we examined how single-gene-deletion mutations affecting trehalose biosynthesis and degradation impact 1 the age-related dynamics of changes in trehalose concentration; 2 yeast chronological lifespan under CR conditions; 3 the chronology of oxidative protein damage, intracellular ROS level and protein aggregation; and 4 the timeline of thermal inactivation of a protein in heat-shocked yeast cells and its subsequent reactivation in yeast returned to low temperature. Our data imply that CR extends yeast chronological lifespan in part by altering a pattern of age-related changes in trehalose concentration. We outline a model for molecular mechanisms underlying the essential role of trehalose in defining yeast longevity by modulating protein folding, misfolding, unfolding, refolding, oxidative damage, solubility and aggregation throughout lifespan.

  4. The effect of aging and caloric restriction on murine CD8+ T cell chemokine receptor gene expression

    Directory of Open Access Journals (Sweden)

    Mo RuRan

    2007-11-01

    Full Text Available Abstract Background The mechanism explaining the increased disease susceptibility in aging is not well understood. CD8+ T cells are crucial in anti-viral and anti-tumor responses. Although the chemokine system plays a critical role in CD8+ T cell function, very little is known about the relationship between aging and the T cell chemokine system. Results In this study we have examined the effect of aging on murine CD8+ T cell chemokine receptor gene expression. Freshly isolated splenic CD8+ T cells from old C57BL/6 mice were found to have higher CCR1, CCR2, CCR4, CCR5 and CXCR5, and lower CCR7 gene expression compared to their younger cohort. Anti-CD3/anti-CD28 stimulation elicited a similar robust chemokine receptor response from young and old CD8+ T cells. Western blot analyses confirmed elevated protein level of CCR4 and CCR5 in aged CD8+ T cells. Increases in T cell CCR1 and CCR5 expression also correlate to increased in vitro chemotaxis response to macrophage-inflammatory protein-1 α(MIP-1α. Finally, caloric restriction selectively prevents the loss of CD8+ T cell CCR7 gene expression in aging to the level that is seen in young CD8+ T cells. Conclusion These findings are consistent with the notion that aging exists in a state of low grade pro-inflammatory environment. In addition, our results provide a potential mechanism for the reported aging-associated impaired T cell lymphoid homing and allograft response, and reduced survival in sepsis.

  5. Effects of Intermittent Fasting, Caloric Restriction, and Ramadan Intermittent Fasting on Cognitive Performance at Rest and During Exercise in Adults.

    Science.gov (United States)

    Cherif, Anissa; Roelands, Bart; Meeusen, Romain; Chamari, Karim

    2016-01-01

    The aim of this review was to highlight the potent effects of intermittent fasting on the cognitive performance of athletes at rest and during exercise. Exercise interacts with dietary factors and has a positive effect on brain functioning. Furthermore, physical activity and exercise can favorably influence brain plasticity. Mounting evidence indicates that exercise, in combination with diet, affects the management of energy metabolism and synaptic plasticity by affecting molecular mechanisms through brain-derived neurotrophic factor, an essential neurotrophin that acts at the interface of metabolism and plasticity. The literature has also shown that certain aspects of physical performance and mental health, such as coping and decision-making strategies, can be negatively affected by daylight fasting. However, there are several types of intermittent fasting. These include caloric restriction, which is distinct from fasting and allows subjects to drink water ad libitum while consuming a very low-calorie food intake. Another type is Ramadan intermittent fasting, which is a religious practice of Islam, where healthy adult Muslims do not eat or drink during daylight hours for 1 month. Other religious practices in Islam (Sunna) also encourage Muslims to practice intermittent fasting outside the month of Ramadan. Several cross-sectional and longitudinal studies have shown that intermittent fasting has crucial effects on physical and intellectual performance by affecting various aspects of bodily physiology and biochemistry that could be important for athletic success. Moreover, recent findings revealed that immunological variables are also involved in cognitive functioning and that intermittent fasting might impact the relationship between cytokine expression in the brain and cognitive deficits, including memory deficits.

  6. Short-term caloric restriction normalizes hypothalamic neuronal responsiveness to glucose ingestion in patients with type 2 diabetes

    NARCIS (Netherlands)

    Teeuwisse, W.M.; Widya, R.L.; Paulides, M.; Lamb, H.J.; Smit, J.W.A.; Roos, A. de; Buchem, M.A. van; Pijl, H.; Grond, J. van der

    2012-01-01

    The hypothalamus is critically involved in the regulation of feeding. Previous studies have shown that glucose ingestion inhibits hypothalamic neuronal activity. However, this was not observed in patients with type 2 diabetes. Restoring energy balance by reducing caloric intake and losing weight are

  7. Protein-pacing caloric-restriction enhances body composition similarly in obese men and women during weight loss and sustains efficacy during long-term weight maintenance

    DEFF Research Database (Denmark)

    Arciero, Paul J; Edmonds, Rohan; He, Feng;

    2016-01-01

    Short-Term protein-pacing (P; ~6 meals/day, >30% protein/day) and caloric restriction (CR, ~25% energy deficit) improves total (TBF), abdominal (ABF) and visceral (VAT) fat loss, energy expenditure, and biomarkers compared to heart healthy (HH) recommendations (3 meals/day, 15% protein/day) in ob......Short-Term protein-pacing (P; ~6 meals/day, >30% protein/day) and caloric restriction (CR, ~25% energy deficit) improves total (TBF), abdominal (ABF) and visceral (VAT) fat loss, energy expenditure, and biomarkers compared to heart healthy (HH) recommendations (3 meals/day, 15% protein....../day) in obese adults. Less is known whether obese men and women respond similarly to P-CR during weight loss (WL) and whether a modified P-CR (mP-CR) is more efficacious than a HH diet during long-term (52 week) weight maintenance (WM). The purposes of this study were to evaluate the efficacy of: (1) P...... and women had similar reductions (p weight (10%), TBF (19%), ABF (25%), VAT (33%), glucose (7%-12%), insulin (40%), leptin (>50%) and increase in % lean body mass (9%). RMR (kcals/kg bodyweight) was unchanged and respiratory quotient decreased 9%. Twenty-four subjects (mP-CR, n = 10; HH, n = 14...

  8. 热量限制与白藜芦醇抗衰老的研究进展%Recent Anti-aging Studies on Caloric Restriction and Resveratrol

    Institute of Scientific and Technical Information of China (English)

    郭燕世

    2011-01-01

    Seventy-five years after its initial report, lifespan prolongation by caloric restriction (CR) has been confirmed in many animal species. Gathered evidences suggest that the histone deacetylase Sir2/ SIRT1 is a key mediator. Moreover, resveratrol (RSV) , a plant derived polyphenol, was shown to increase SIRT1 catalytic activity and mimics many aspects of CR in all eukaryotes tested. Therefore, RSV displays great promise in the prevention of illness and delay the aging process.%限制热量摄取(caloric restriction,CR) 能够延长寿命,这个75 年前的发现己得到广泛的证明.其作用主要是由去乙酰化酶 (Sir2/SIRT1)所介导.近年又发现,植物中的多酚化物--白藜芦醇,是SIRT1 的激活剂,它能够模拟 CR 的抗衰老作用,并能防治多种疾病.因此它有可能成为人类防病和抗衰老的有用工具.

  9. Effects of the dietary approaches to stop hypertension diet, exercise, and caloric restriction on neurocognition in overweight adults with high blood pressure.

    Science.gov (United States)

    Smith, Patrick J; Blumenthal, James A; Babyak, Michael A; Craighead, Linda; Welsh-Bohmer, Kathleen A; Browndyke, Jeffrey N; Strauman, Timothy A; Sherwood, Andrew

    2010-06-01

    High blood pressure increases the risks of stroke, dementia, and neurocognitive dysfunction. Although aerobic exercise and dietary modifications have been shown to reduce blood pressure, no randomized trials have examined the effects of aerobic exercise combined with dietary modification on neurocognitive functioning in individuals with high blood pressure (ie, prehypertension and stage 1 hypertension). As part of a larger investigation, 124 participants with elevated blood pressure (systolic blood pressure 130 to 159 mm Hg or diastolic blood pressure 85 to 99 mm Hg) who were sedentary and overweight or obese (body mass index: 25 to 40 kg/m(2)) were randomized to the Dietary Approaches to Stop Hypertension (DASH) diet alone, DASH combined with a behavioral weight management program including exercise and caloric restriction, or a usual diet control group. Participants completed a battery of neurocognitive tests of executive function-memory-learning and psychomotor speed at baseline and again after the 4-month intervention. Participants on the DASH diet combined with a behavioral weight management program exhibited greater improvements in executive function-memory-learning (Cohen's D=0.562; P=0.008) and psychomotor speed (Cohen's D=0.480; P=0.023), and DASH diet alone participants exhibited better psychomotor speed (Cohen's D=0.440; P=0.036) compared with the usual diet control. Neurocognitive improvements appeared to be mediated by increased aerobic fitness and weight loss. Also, participants with greater intima-medial thickness and higher systolic blood pressure showed greater improvements in executive function-memory-learning in the group on the DASH diet combined with a behavioral weight management program. In conclusion, combining aerobic exercise with the DASH diet and caloric restriction improves neurocognitive function among sedentary and overweight/obese individuals with prehypertension and hypertension.

  10. Cell death-inducing DFF45-like effector C is reduced by caloric restriction and regulates adipocyte lipid metabolism.

    Science.gov (United States)

    Magnusson, Björn; Gummesson, Anders; Glad, Camilla A M; Goedecke, Julia H; Jernås, Margareta; Lystig, Theodore C; Carlsson, Björn; Fagerberg, Björn; Carlsson, Lena M S; Svensson, Per-Arne

    2008-09-01

    Members of the cell death-inducing DFF45-like effector (CIDE) gene family have been shown to regulate lipid metabolism. In this article, we report that the third member of the human CIDE family, CIDEC, is down-regulated in response to a reduced caloric intake. The down-regulation was demonstrated by microarray and real-time polymerase chain reaction analysis of subcutaneous adipose tissue in 2 independent studies on obese patients undergoing treatment with a very low calorie diet. By analysis of CIDEC expression in 65 human tissues, we conclude that human CIDEC is predominantly expressed in subcutaneous adipocytes. Together, these observations led us to investigate the effect of decreased CIDEC expression in cultured 3T3-L1 adipocytes. Small interfering RNA-mediated knockdown of CIDEC resulted in an increased basal release of nonesterified fatty acids, decreased responsiveness to adrenergic stimulation of lipolysis, and increased oxidation of endogenous fatty acids. Thus, we suggest that CIDEC is a regulator of adipocyte lipid metabolism and may be important for the adipocyte to adapt to changes in energy availability.

  11. Caloric restriction or resveratrol supplementation and ageing in a non-human primate: first-year outcome of the RESTRIKAL study in Microcebus murinus.

    Science.gov (United States)

    Dal-Pan, Alexandre; Terrien, Jérémy; Pifferi, Fabien; Botalla, Roger; Hardy, Isabelle; Marchal, Julia; Zahariev, Alexandre; Chery, Isabelle; Zizzari, Philippe; Perret, Martine; Picq, Jean Luc; Epelbaum, Jacques; Blanc, Stéphane; Aujard, Fabienne

    2011-03-01

    A life-long follow-up of physiological and behavioural functions was initiated in 38-month-old mouse lemurs (Microcebus murinus) to test whether caloric restriction (CR) or a potential mimetic compound, resveratrol (RSV), can delay the ageing process and the onset of age-related diseases. Based on their potential survival of 12 years, mouse lemurs were assigned to three different groups: a control (CTL) group fed ad libitum, a CR group fed 70% of the CTL caloric intake and a RSV group (200 mg/kg.day(-1)) fed ad libitum. Since this prosimian primate exhibits a marked annual rhythm in body mass gain during winter, animals were tested throughout the year to assess body composition, daily energy expenditure (DEE), resting metabolic rate (RMR), physical activity and hormonal levels. After 1 year, all mouse lemurs seemed in good health. CR animals showed a significantly decreased body mass compared with the other groups during long day period only. CR or RSV treatments did not affect body composition. CR induced a decrease in DEE without changes in RMR, whereas RSV induced a concomitant increase in DEE and RMR without any obvious modification of locomotor activity in both groups. Hormonal levels remained similar in each group. In summary, after 1 year of treatment CR and RSV induced differential metabolic responses but animals successfully acclimated to their imposed diets. The RESTRIKAL study can now be safely undertaken on a long-term basis to determine whether age-associated alterations in mouse lemurs are delayed with CR and if RSV can mimic these effects.

  12. Mild and Short-Term Caloric Restriction Prevents Obesity-Induced Cardiomyopathy in Young Zucker Rats without Changing in Metabolites and Fatty Acids Cardiac Profile

    Science.gov (United States)

    Ruiz-Hurtado, Gema; García-Prieto, Concha F.; Pulido-Olmo, Helena; Velasco-Martín, Juan P.; Villa-Valverde, Palmira; Fernández-Valle, María E.; Boscá, Lisardo; Fernández-Velasco, María; Regadera, Javier; Somoza, Beatriz; Fernández-Alfonso, María S.

    2017-01-01

    Caloric restriction (CR) ameliorates cardiac dysfunction associated with obesity. However, most of the studies have been performed under severe CR (30–65% caloric intake decrease) for several months or even years in aged animals. Here, we investigated whether mild (20% food intake reduction) and short-term (2-weeks) CR prevented the obese cardiomyopathy phenotype and improved the metabolic profile of young (14 weeks of age) genetically obese Zucker fa/fa rats. Heart weight (HW) and HW/tibia length ratio was significantly lower in fa/fa rats after 2 weeks of CR than in counterparts fed ad libitum. Invasive pressure measurements showed that systolic blood pressure, maximal rate of positive left ventricle (LV) pressure, LV systolic pressure and LV end-diastolic pressure were all significantly higher in obese fa/fa rats than in lean counterparts, which were prevented by CR. Magnetic resonance imaging revealed that the increase in LV end-systolic volume, stroke volume and LV wall thickness observed in fa/fa rats was significantly lower in animals on CR diet. Histological analysis also revealed that CR blocked the significant increase in cardiomyocyte diameter in obese fa/fa rats. High resolution magic angle spinning magnetic resonance spectroscopy analysis of the LV revealed a global decrease in metabolites such as taurine, creatine and phosphocreatine, glutamate, glutamine and glutathione, in obese fa/fa rats, whereas lactate concentration was increased. By contrast, fatty acid concentrations in LV tissue were significantly elevated in obese fa/fa rats. CR failed to restore the LV metabolomic profile of obese fa/fa rats. In conclusion, mild and short-term CR prevented an obesity-induced cardiomyopathy phenotype in young obese fa/fa rats independently of the cardiac metabolic profile. PMID:28203206

  13. Caloric restriction and the adipokine leptin alter the SDF-1 signaling axis in bone marrow and in bone marrow derived mesenchymal stem cells.

    Science.gov (United States)

    Periyasamy-Thandavan, Sudharsan; Herberg, Samuel; Arounleut, Phonepasong; Upadhyay, Sunil; Dukes, Amy; Davis, Colleen; Johnson, Maribeth; McGee-Lawrence, Meghan; Hamrick, Mark W; Isales, Carlos M; Hill, William D

    2015-07-15

    Growing evidence suggests that the chemokine stromal cell-derived factor-1 (SDF-1) is essential in regulating bone marrow (BM) derived mesenchymal stromal/stem cell (BMSC) survival, and differentiation to either a pro-osteogenic or pro-adipogenic fate. This study investigates the effects of caloric restriction (CR) and leptin on the SDF-1/CXCR4 axis in bone and BM tissues in the context of age-associated bone loss. For in vivo studies, we collected bone, BM cells and BM interstitial fluid from 12 and 20 month-old C57Bl6 mice fed ad-libitum (AL), and 20-month-old mice on long-term CR with, or without, intraperitoneal injection of leptin for 10 days (10 mg/kg). To mimic conditions of CR in vitro, 18 month murine BMSCs were treated with (1) control (Ctrl): normal proliferation medium, (2) nutrient restriction (NR): low glucose, low serum medium, or (3) NR + leptin: NR medium + 100 ng/ml leptin for 6-48 h. In BMSCs both protein and mRNA expression of SDF-1 and CXCR4 were increased by CR and CR + leptin. In contrast, the alternate SDF-1 receptor CXCR7 was decreased, suggesting a nutrient signaling mediated change in SDF-1 axis signaling in BMSCs. However, in bone SDF-1, CXCR4 and 7 gene expression increase with age and this is reversed with CR, while addition of leptin returns this to the "aged" level. Histologically bone formation was lower in the calorically restricted mice and BM adipogenesis increased, both effects were reversed with the 10 day leptin treatment. This suggests that in bone CR and leptin alter the nutrient signaling pathways in different ways to affect the local action of the osteogenic cytokine SDF-1. Studies focusing on the molecular interaction between nutrient signaling by CR, leptin and SDF-1 axis may help to address age-related musculoskeletal changes.

  14. Management of multifactorial idiopathic epilepsy in EL mice with caloric restriction and the ketogenic diet: role of glucose and ketone bodies

    Directory of Open Access Journals (Sweden)

    Mantis John G

    2004-10-01

    Full Text Available Abstract Background The high fat, low carbohydrate ketogenic diet (KD was developed as an alternative to fasting for seizure management. While the mechanisms by which fasting and the KD inhibit seizures remain speculative, alterations in brain energy metabolism are likely involved. We previously showed that caloric restriction (CR inhibits seizure susceptibility by reducing blood glucose in the epileptic EL mouse, a natural model for human multifactorial idiopathic epilepsy. In this study, we compared the antiepileptic and anticonvulsant efficacy of the KD with that of CR in adult EL mice with active epilepsy. EL mice that experienced at least 15 recurrent complex partial seizures were fed either a standard diet unrestricted (SD-UR or restricted (SD-R, and either a KD unrestricted (KD-UR or restricted (KD-R. All mice were fasted for 14 hrs prior to diet initiation. A new experimental design was used where each mouse in the diet-restricted groups served as its own control to achieve a 20–23% body weight reduction. Seizure susceptibility, body weights, and the levels of plasma glucose and β-hydroxybutyrate were measured once/week over a nine-week treatment period. Results Body weights and blood glucose levels remained high over the testing period in the SD-UR and the KD-UR groups, but were significantly (p Conclusions The results indicate that seizure susceptibility in EL mice is dependent on plasma glucose levels and that seizure control is more associated with the amount than with the origin of dietary calories. Also, CR underlies the antiepileptic and anticonvulsant action of the KD in EL mice. A transition from glucose to ketone bodies for energy is predicted to manage EL epileptic seizures through multiple integrated changes of inhibitory and excitatory neural systems.

  15. The data do not seem to support a benefit to BCAA supplementation during periods of caloric restriction.

    Science.gov (United States)

    Dieter, Brad P; Schoenfeld, Brad Jon; Aragon, Alan A

    2016-01-01

    J Int Soc Sports Nutr 13:1-015-0112-9, 2016 describe the efficacy of branched chain amino acid (BCAA) supplementation and resistance training for maintaining lean body mass during a calorie-restricted diet, and claim that this occurs with concurrent losses in fat mass. However, the reported results appear to be at odds with the data presented on changes in fat mass. This letter discusses the issues with the paper.

  16. Reduction in the body content of DDE in the Mongolian gerbil treated with sucrose polyester and caloric restriction

    Energy Technology Data Exchange (ETDEWEB)

    Mutter, L.C.; Blanke, R.V.; Jandacek, R.J.; Guzelian, P.S.

    1988-03-15

    It has previously been shown that oral administration to rats of sucrose polyester (SPE4), a nonabsorbable lipophilic binding agent, greatly stimulates the fecal excretion of coorally administered DDT5. To determine whether this agent would stimulate the excretion of persistent metabolites of DDT stored in body tissues, we treated a group of gerbils with (/sup 14/C)-DDT and monitored the fecal excretion of radioactivity for several months until a terminal, log-linear phase of excretion was observed. At this point, when greater than 75% of the fecal radioactivity was identified as (/sup 14/C)DDE, we fed the animals diets containing up to 10% sucrose polyester and found that the rate of excretion of radioactivity in the stool promptly increased two to three times as compared to the rate in the preceding control period. Some rats were subjected to a 25-50% restriction in total food allotment, but this produced no significant change in fecal excretion of total radioactivity. However, when food restriction was combined with administration of sucrose polyester, there was a dramatic, eightfold average increase in excretion of fecal radioactivity. This synergistic effect was reversed (within 24 hr) when the animals were transferred to a normal diet. Measurement of total body radioactivity confirmed that food restriction plus sucrose polyester treatment reduced the body content of the pesticide. We conclude that stimulation of intestinal excretion may offer a new approach to treatment of patients exposed to lipophilic environmental contaminants.

  17. How much should we weigh for a long and healthy life span?The need to reconcile caloric restriction versus longevity with body mass index versus mortality data.

    Directory of Open Access Journals (Sweden)

    Antonello eLorenzini

    2014-07-01

    Full Text Available Total caloric restriction (CR without malnutrition is a well-established experimental approach to extend life span in laboratory animals. Although CR in humans is capable of shifting several endocrinological parameters it is not clear where the minimum inflection point of the U shaped curve linking body mass index (BMI with all-cause mortality lies. The exact trend of this curve, when used for planning preventive strategies for public health is of extreme importance. Normal BMI ranges from 18.5 to 24.9; many epidemiological studies show an inverse relationship between mortality and BMI inside the normal BMI range. Other studies show that the lowest mortality in the entire range of BMI is obtained in the overweight range (25 to 29.9. Reconciling the extension of life span in laboratory animals by experimental CR with the BMI-mortality curve of human epidemiology is not trivial. In fact, one interpretation is that the CR data are identifying a known: excess fat is deleterious for health; although a second interpretation may be that: additional leanness from a normal body weight may add health and life span delaying the process of aging. This short review hope to start a discussion aimed at finding the widest consensus on which weight range should be consider the healthiest for our species, contributing in this way to the picture of what is the correct life style for a long and healthy life span.

  18. Lactobacillus fermentum CRL1446 Ameliorates Oxidative and Metabolic Parameters by Increasing Intestinal Feruloyl Esterase Activity and Modulating Microbiota in Caloric-Restricted Mice

    Directory of Open Access Journals (Sweden)

    Matias Russo

    2016-07-01

    Full Text Available The purpose of this study was to determine whether the administration of the feruloyl esterase (FE-producing strain Lactobacillus fermentum CRL1446 enhances metabolic and oxidative parameters in caloric-restricted (CR mice. Balb/c male mice were divided into ad libitum fed Group (ALF Group, CR diet Group (CR Group and CR diet plus L. fermentum Group (CR-Lf Group. CR diet was administered during 45 days and CRL1446 strain was given in the dose of 108 cells/mL/day/mouse. FE activity was determined in intestinal mucosa and content at Day 1, 20 and 45. Triglyceride, total cholesterol, glucose, thiobarbituric acid reactive substances (TBARS levels and glutathione reductase activity were determined in plasma. Gut microbiota was evaluated by high-throughput sequencing of 16S rRNA gene amplicons. At Day 45, total intestinal FE activity in CR-Lf Group was higher (p = 0.020 than in CR and ALF groups and an improvement in both metabolic (reductions in triglyceride (p = 0.0025, total cholesterol (p = 0.005 and glucose (p < 0.0001 levels and oxidative (decrease of TBARS levels and increase of plasmatic glutathione reductase activity (p = 0.006 parameters was observed, compared to ALF Group. CR diet increased abundance of Bacteroidetes and CRL1446 administration increased abundance of Bifidobacterium and Lactobacillus genus. L. fermentun CRL1446 exerted a bifidogenic effect under CR conditions.

  19. The lifespan extension effects of resveratrol are conserved in the honey bee and may be driven by a mechanism related to caloric restriction.

    Science.gov (United States)

    Rascón, Brenda; Hubbard, Basil P; Sinclair, David A; Amdam, Gro V

    2012-07-01

    Our interest in healthy aging and in evolutionarily conserved mechanisms of lifespan extension prompted us to investigate whether features of age-related decline in the honey bee could be attenuated with resveratrol. Resveratrol is regarded as a caloric restriction mimetic known to extend lifespan in some but not all model species. The current, prevailing view is that resveratrol works largely by activating signaling pathways. It has also been suggested that resveratrol may act as an antioxidant and confer protection against nervous system impairment and oxidative stress. To test whether honey bee lifespan, learning performance, and food perception could be altered by resveratrol, we supplemented the diets of honey bees and measured lifespan, olfactory learning, and gustatory responsiveness to sucrose. Furthermore, to test the effects of resveratrol under metabolic challenge, we used hyperoxic environments to generate oxidative stress. Under normal oxygen conditions, two resveratrol treatments-30 and 130 μM-lengthened average lifespan in wild-type honey bees by 38% and 33%, respectively. Both resveratrol treatments also lengthened maximum and median lifespan. In contrast, hyperoxic stress abolished the resveratrol life-extension response. Furthermore, resveratrol did not affect learning performance, but did alter gustation. Honey bees that were not fed resveratrol exhibited greater responsiveness to sugar, while those supplemented with resveratrol were less responsive to sugar. We also discovered that individuals fed a high dose of resveratrol-compared to controls-ingested fewer quantities of food under ad libitum feeding conditions.

  20. Anti-oxidative and anti-inflammatory vasoprotective effects of caloric restriction in aging: role of circulating factors and SIRT1.

    Science.gov (United States)

    Csiszar, Anna; Labinskyy, Nazar; Jimenez, Rosario; Pinto, John T; Ballabh, Praveen; Losonczy, Gyorgy; Pearson, Kevin J; de Cabo, Rafael; Ungvari, Zoltan

    2009-08-01

    Endothelial dysfunction, oxidative stress and inflammation are associated with vascular aging and promote the development of cardiovascular disease. Caloric restriction (CR) mitigates conditions associated with aging, but its effects on vascular dysfunction during aging remain poorly defined. To determine whether CR exerts vasoprotective effects in aging, aortas of ad libitum (AL) fed young and aged and CR-aged F344 rats were compared. Aging in AL-rats was associated with impaired acetylcholine-induced relaxation, vascular oxidative stress and increased NF-kappaB activity. Lifelong CR significantly improved endothelial function, attenuated vascular ROS production, inhibited NF-kappaB activity and down-regulated inflammatory genes. To elucidate the role of circulating factors in mediation of the vasoprotective effects of CR, we determined whether sera obtained from CR animals can confer anti-oxidant and anti-inflammatory effects in cultured coronary arterial endothelial cells (CAECs), mimicking the effects of CR. In CAECs cultured in the presence of AL serum TNFalpha elicited oxidative stress, NF-kappaB activation and inflammatory gene expression. By contrast, treatment of CAECs with CR serum attenuated TNFalpha-induced ROS generation and prevented NF-kappaB activation and induction of inflammatory genes. siRNA knockdown of SIRT1 mitigated the anti-oxidant and anti-inflammatory effects of CR serum. CR exerts anti-oxidant and anti-inflammatory vascular effects, which are likely mediated by circulating factors, in part, via a SIRT1-dependent pathway.

  1. Lactobacillus fermentum CRL1446 Ameliorates Oxidative and Metabolic Parameters by Increasing Intestinal Feruloyl Esterase Activity and Modulating Microbiota in Caloric-Restricted Mice

    Science.gov (United States)

    Russo, Matias; Fabersani, Emanuel; Abeijón-Mukdsi, María C.; Ross, Romina; Fontana, Cecilia; Benítez-Páez, Alfonso; Gauffin-Cano, Paola; Medina, Roxana B.

    2016-01-01

    The purpose of this study was to determine whether the administration of the feruloyl esterase (FE)-producing strain Lactobacillus fermentum CRL1446 enhances metabolic and oxidative parameters in caloric-restricted (CR) mice. Balb/c male mice were divided into ad libitum fed Group (ALF Group), CR diet Group (CR Group) and CR diet plus L. fermentum Group (CR-Lf Group). CR diet was administered during 45 days and CRL1446 strain was given in the dose of 108 cells/mL/day/mouse. FE activity was determined in intestinal mucosa and content at Day 1, 20 and 45. Triglyceride, total cholesterol, glucose, thiobarbituric acid reactive substances (TBARS) levels and glutathione reductase activity were determined in plasma. Gut microbiota was evaluated by high-throughput sequencing of 16S rRNA gene amplicons. At Day 45, total intestinal FE activity in CR-Lf Group was higher (p = 0.020) than in CR and ALF groups and an improvement in both metabolic (reductions in triglyceride (p = 0.0025), total cholesterol (p = 0.005) and glucose (p < 0.0001) levels) and oxidative (decrease of TBARS levels and increase of plasmatic glutathione reductase activity (p = 0.006)) parameters was observed, compared to ALF Group. CR diet increased abundance of Bacteroidetes and CRL1446 administration increased abundance of Bifidobacterium and Lactobacillus genus. L. fermentun CRL1446 exerted a bifidogenic effect under CR conditions. PMID:27399766

  2. Differential Development of Inflammation and Insulin Resistance in Different Adipose Tissue Depots Along Aging in Wistar Rats: Effects of Caloric Restriction.

    Science.gov (United States)

    Sierra Rojas, Johanna X; García-San Frutos, Miriam; Horrillo, Daniel; Lauzurica, Nuria; Oliveros, Eva; Carrascosa, Jose María; Fernández-Agulló, Teresa; Ros, Manuel

    2016-03-01

    The prevalence of insulin resistance and type 2 diabetes increases with aging and these disorders are associated with inflammation. Insulin resistance and inflammation do not develop at the same time in all tissues. Adipose tissue is one of the tissues where inflammation and insulin resistance are established earlier during aging. Nevertheless, the existence of different fat depots states the possibility of differential roles for these depots in the development of age-associated inflammation and insulin resistance. To explore this, we analyzed insulin signaling and inflammation in epididymal, perirenal, subcutaneous, and brown adipose tissues during aging in Wistar rats. Although all tissues showed signs of inflammation and insulin resistance with aging, epididymal fat was the first to develop signs of inflammation and insulin resistance along aging among white fat tissues. Subcutaneous adipose tissue presented the lowest degree of inflammation and insulin resistance that developed latter with age. Brown adipose tissue also presented latter insulin resistance and inflammation but with lower signs of macrophage infiltration. Caloric restriction ameliorated insulin resistance and inflammation in all tissues, being more effective in subcutaneous and brown adipose tissues. These data demonstrate differential susceptibility of the different adipose depots to the development of age-associated insulin resistance and inflammation.

  3. Prevention of neuromusculoskeletal frailty in slow-aging ames dwarf mice: longitudinal investigation of interaction of longevity genes and caloric restriction.

    Directory of Open Access Journals (Sweden)

    Oge Arum

    Full Text Available Ames dwarf (Prop1 (df/df mice are remarkably long-lived and exhibit many characteristics of delayed aging and extended healthspan. Caloric restriction (CR has similar effects on healthspan and lifespan, and causes an extension of longevity in Ames dwarf mice. Our study objective was to determine whether Ames dwarfism or CR influence neuromusculoskeletal function in middle-aged (82 ± 12 weeks old or old (128 ± 14 w.o. mice. At the examined ages, strength was improved by dwarfism, CR, and dwarfism plus CR in male mice; balance/ motor coordination was improved by CR in old animals and in middle-aged females; and agility/ motor coordination was improved by a combination of dwarfism and CR in both genders of middle-aged mice and in old females. Therefore, extension of longevity by congenital hypopituitarism is associated with improved maintenance of the examined measures of strength, agility, and motor coordination, key elements of frailty during human aging, into advanced age. This study serves as a particularly important example of knowledge related to addressing aging-associated diseases and disorders that results from studies in long-lived mammals.

  4. Vitamin E and caloric restriction promote hepatic homeostasis through expression of connexin 26, N-cad, E-cad and cholesterol metabolism genes.

    Science.gov (United States)

    Santolim, Leonardo Vinícius; Amaral, Maria Esméria Corezola do; Fachi, José Luís; Mendes, Maíra Felonato; Oliveira, Camila Andréa de

    2017-01-01

    Connexins (Cx) and cadherins are responsible for cell homeostasis. The Cx activity is directly related to cholesterol. The present work investigates whether vitamin E, with or without caloric restriction (CR), alters the mRNA expression of Cx26, Cx32, Cx43, N-cadherins (N-cads), E-cadherins (E-cads) and alpha-smooth muscle actin (α-SMA), and evaluates their relation to cholesterol metabolism in rat liver. Animals were divided into different groups: control with ad libitum diet (C), control+vitamin E (CV), aloric restriction with intake to 60% of group C (CR), and the intake of group CR+vitamin E (RV). There were increases of manganese superoxide dismutase (Mn-SOD) and glutathione S-transferase mu 1, indicating antioxidant effects of CR and vitamin E. An increase of nitric oxide in the CR group was in agreement with the Mn-SOD data. Supplementation with vitamin E, with or without CR, upregulated the expression of Cx26 mRNA and increased low-density lipoprotein cholesterol (LDL-c) in the CV group. Reductions of Cx32 and Cx43 were associated with lower LDL-c. Increases in Hmgcr and low-density lipoprotein receptor (LDLr) in the CV and RV groups could be explained by the effect of vitamin E. A reduction of LDLr in the CR group was due to the reduced dietary intake. Increases in cadherins in the CV, CR and RV groups were indicative of tissue maintenance, which was also supported by increases of α-SMA in groups CV and RV. Finally, vitamin E, with or without CR, increased Cx26, probably modulated by expression of the Hmgcr and LDLr genes. This suggests important relationship of Cxs and cholesterol metabolism genes.

  5. Inhibitory Effect of Estrogens, Phytoestrogens, and Caloric Restriction on Oxidative Stress and Hepato-toxicity in Aged Rats

    Institute of Scientific and Technical Information of China (English)

    KHALED HAMDEN; SERGE CARREAU; FATMA AYADI; HATEM MASMOUDI; ABDELFATTAH EL FEKI

    2009-01-01

    Objective To investigate the protective effect of 17β-estradiol (E2), peganum harmala extract (PHE) administration and calorie restriction (CR) treatment (60%) on oxidative stress and hepato-toxicity in aged rats. Methods Eighteen months old animals that were treated at the age of 12 months were divided into 4 groups: normal control group with free access to food, E2 treatment group, PHE treatment group and CR treatment group of the food given to control group. Six male rats at the age of 4 months were used as a reference group. Results Aging significantly decreased superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPX), and increased lactate deshydrogenase (LDH), gamma-glytamyl transferase (GGT), phosphatase alkalines (PAL), aspartate and lactate transaminase (AST and ALT) activities in the liver. Aging also induced an increased lipid peroxidation level, histological changes and a decreased E2 level. However, treatment with E2, PHE, and CR increased 17β-estradiol, and decreased hepatic dysfunction parameters and lipid peroxidation as well as histological changes in the liver of aged rats. Conclusion The antioxidant and hepatoprotective activity of PHE and CR is possibly attributed to its ability to increase E2 level, which as an antioxidant, acts as a scavenger of ROS. Further studies on the pharmaceutical functions of E2 in males may contribute to its clinical application.

  6. Metabolically distinct weight loss by 10,12 CLA and caloric restriction highlight the importance of subcutaneous white adipose tissue for glucose homeostasis in mice

    Science.gov (United States)

    Wang, Shari; Goodspeed, Leela; Wietecha, Tomasz; Houston, Barbara; Omer, Mohamed; Ogimoto, Kayoko; Subramanian, Savitha; Gowda, G. A. Nagana; O’Brien, Kevin D.; Kaiyala, Karl J.; Morton, Gregory J.; Chait, Alan

    2017-01-01

    Background Widely used as a weight loss supplement, trans-10,cis-12 conjugated linoleic acid (10,12 CLA) promotes fat loss in obese mice and humans, but has also been associated with insulin resistance. Objective We therefore sought to directly compare weight loss by 10,12 CLA versus caloric restriction (CR, 15–25%), an acceptable healthy method of weight loss, to determine how 10,12 CLA-mediated weight loss fails to improve glucose metabolism. Methods Obese mice with characteristics of human metabolic syndrome were either supplemented with 10,12 CLA or subjected to CR to promote weight loss. Metabolic endpoints such as energy expenditure, glucose and insulin tolerance testing, and trunk fat distribution were measured. Results By design, 10,12 CLA and CR caused equivalent weight loss, with greater fat loss by 10,12 CLA accompanied by increased energy expenditure, reduced respiratory quotient, increased fat oxidation, accumulation of alternatively activated macrophages, and browning of subcutaneous white adipose tissue (WAT). Moreover, 10,12 CLA-supplemented mice better defended their body temperature against a cold challenge. However, 10,12 CLA concurrently induced the detrimental loss of subcutaneous WAT without reducing visceral WAT, promoted reduced plasma and WAT adipokine levels, worsened hepatic steatosis, and failed to improve glucose metabolism. Obese mice undergoing CR were protected from subcutaneous-specific fat loss, had improved hepatic steatosis, and subsequently showed the expected improvements in WAT adipokines, glucose metabolism and WAT inflammation. Conclusions These results suggest that 10,12 CLA mediates the preferential loss of subcutaneous fat that likely contributes to hepatic steatosis and maintained insulin resistance, despite significant weight loss and WAT browning in mice. Collectively, we have shown that weight loss due to 10,12 CLA supplementation or CR results in dramatically different metabolic phenotypes, with the latter

  7. Interaction of growth hormone receptor/binding protein gene disruption and caloric restriction for insulin sensitivity and attenuated aging [v1; ref status: indexed, http://f1000r.es/4fk

    Directory of Open Access Journals (Sweden)

    Oge Arum

    2014-10-01

    Full Text Available The correlation of physiological sensitivity to insulin (vis-à-vis glycemic regulation and longevity is extensively established, creating a justifiable gerontological interest on whether insulin sensitivity is causative, or even predictive, of some or all phenotypes of slowed senescence (including longevity. The growth hormone receptor/ binding protein gene-disrupted (GHR-KO mouse is the most extensively investigated insulin-sensitive, attenuated aging model. It was reported that, in a manner divergent from similar mutants, GHR-KO mice fail to respond to caloric restriction (CR by altering their insulin sensitivity. We hypothesized that maximized insulin responsiveness is what causes GHR-KO mice to exhibit a suppressed survivorship response to dietary (including caloric restriction; and attempted to refute this hypothesis by assessing the effects of CR on GHR-KO mice for varied slow-aging-associated phenotypes. In contrast to previous reports, we found GHR-KO mice on CR to be less responsive than their ad libitum (A.L. counterparts to the hypoglycemia-inducing effects of insulin. Further, CR had negligible effects on the metabolism or cognition of GHR-KO mice. Therefore, our data suggest that the effects of CR on the insulin sensitivity of GHR-KO mice do not concur with the effects of CR on the aging of GHR-KO mice.

  8. Maternal caloric restriction implemented during the preconceptional and pregnancy period alters hypothalamic and hippocampal endocannabinoid levels at birth and induces overweight and increased adiposity at adulthood in male rat offspring

    Directory of Open Access Journals (Sweden)

    MARÍA TERESA RAMÍREZ-LÓPEZ

    2016-11-01

    Full Text Available Exposure to inadequate nutritional conditions in critical windows of development has been associated to disturbances on metabolism and behavior in the offspring later in life. The role of the endocannabinoid system, a known regulator of energy expenditure and adaptive behaviors, in the modulation of these processes is unknown. In the present study, we investigated the impact of exposing rat dams to diet restriction (20% less calories than standard diet during pre-gestational and gestational periods on a neonatal outcomes, b endocannabinoid content in hypothalamus, hippocampus and olfactory bulb at birth, c metabolism-related parameters, and d behavior in adult male offspring. We found that calorie-restricted dams tended to have a reduced litter size, although the offspring showed normal weight at birth. Pups from calorie-restricted dams also exhibited a strong decrease in the levels of anandamide (AEA, 2-arachidonoylglycerol (2-AG, arachidonic acid (AA and palmitoylethanolamide (PEA in the hypothalamus at birth. Additionally, pups from diet-restricted dams displayed reduced levels of AEA in the hippocampus without significant differences in the olfactory bulb. Moreover, offspring exhibited increased weight gain, body weight and adiposity in adulthood as well as increased anxiety-related responses. We propose that endocannabinoid signaling is altered by a maternal caloric restriction implemented during the preconceptional and pregnancy periods, which might lead to modifications of the hypothalamic and hippocampal circuits, potentially contributing to the long-term effects found in the adult offspring.

  9. Maternal Caloric Restriction Implemented during the Preconceptional and Pregnancy Period Alters Hypothalamic and Hippocampal Endocannabinoid Levels at Birth and Induces Overweight and Increased Adiposity at Adulthood in Male Rat Offspring

    Science.gov (United States)

    Ramírez-López, María Teresa; Vázquez, Mariam; Bindila, Laura; Lomazzo, Ermelinda; Hofmann, Clementine; Blanco, Rosarío Noemí; Alén, Francisco; Antón, María; Decara, Juan; Arco, Rocío; Ouro, Daniel; Orio, Laura; Suárez, Juan; Lutz, Beat; Gómez de Heras, Raquel; Rodríguez de Fonseca, Fernando

    2016-01-01

    Exposure to inadequate nutritional conditions in critical windows of development has been associated to disturbances on metabolism and behavior in the offspring later in life. The role of the endocannabinoid system, a known regulator of energy expenditure and adaptive behaviors, in the modulation of these processes is unknown. In the present study, we investigated the impact of exposing rat dams to diet restriction (20% less calories than standard diet) during pre-gestational and gestational periods on: (a) neonatal outcomes; (b) endocannabinoid content in hypothalamus, hippocampus and olfactory bulb at birth; (c) metabolism-related parameters; and (d) behavior in adult male offspring. We found that calorie-restricted dams tended to have a reduced litter size, although the offspring showed normal weight at birth. Pups from calorie-restricted dams also exhibited a strong decrease in the levels of anandamide (AEA), 2-arachidonoylglycerol (2-AG), arachidonic acid (AA) and palmitoylethanolamide (PEA) in the hypothalamus at birth. Additionally, pups from diet-restricted dams displayed reduced levels of AEA in the hippocampus without significant differences in the olfactory bulb. Moreover, offspring exhibited increased weight gain, body weight and adiposity in adulthood as well as increased anxiety-related responses. We propose that endocannabinoid signaling is altered by a maternal caloric restriction implemented during the preconceptional and pregnancy periods, which might lead to modifications of the hypothalamic and hippocampal circuits, potentially contributing to the long-term effects found in the adult offspring. PMID:27847471

  10. Combination of recreational soccer and caloric restricted diet reduces markers of protein catabolism and cardiovascular risk in patients with type 2 diabetes

    DEFF Research Database (Denmark)

    de Sousa, M Vieira; Fukui, R; Krustrup, Peter

    2017-01-01

    Background: Moderate calorie-restricted diets and exercise training prevent loss of lean mass and cardiovascular risk. Because adherence to routine exercise recommendation is generally poor, we utilized recreational soccer training as a novel therapeutic exercise intervention in type 2 diabetes (T2......D) patients. Objective: We compared the effects of acute and chronic soccer training plus calorie-restricted diet on protein catabolism and cardiovascular risk markers in T2D. Design, setting and subjects: Fifty-one T2D patients (61.1±6.4 years, 29 females: 22 males) were randomly allocated...

  11. A weekly alternating diet between caloric restriction and medium-fat protects the liver from fatty liver development in middle-aged C57BL/6J mice

    NARCIS (Netherlands)

    Rusli, F.; Boekschoten, M.V.; Zubia, A.A.; Lute, C.; Müller, M.R.; Steegenga, W.T.

    2015-01-01

    Scope : We aimed to investigate whether a novel dietary intervention consisting of an every-other-week calorie restricted diet could prevent non-alcoholic fatty liver disease (NAFLD) development induced by a medium-fat diet. Methods and results : Nine week-old male C57BL/6J mice received either a 1)

  12. Effects of caloric restriction therapy on nonalcoholic fatty liver disease%限食疗法对非酒精性脂肪性肝病的治疗作用

    Institute of Scientific and Technical Information of China (English)

    李春睿; 陈国芳; 刘超; 蔡可英

    2013-01-01

    作为一种代谢性疾病,非酒精性脂肪性肝病的治疗主要是生活方式干预.限食疗法作为生活方式干预的一种,已被证实可减轻患者的体重、减少肝脏内脂肪含量、减轻胰岛素抵抗,改善其他代谢异常.而且,有研究认为,不同方式的限食对该病的治疗效果存在差异,低脂及低碳水化合物限食对其治疗效果优于低热量限食,这值得进一步研究探索.%As a type of metabolic disease,the treatment of nonalcoholic fatty liver disease (NAFLD)mainly depends on lifestyle intervention.Caloric restriction therapy (CR) is one kind of lifestyle intervention,which is reported to be effective to reduce the patients'weight,decrease intrahepatic triglyceride,alleviate insulin resistance,and improve other metabolic disorders.Moreover,some researches have shown the different effect on NAFLD among different CR.Low-fat diet and low-carbohydrate diet have shown better effect than low-calorie diet,but it needs more studies.

  13. Relationship of adipokine to insulin sensitivity and glycemic regulation in obese women: The effect of body weight reduction by caloric restriction

    Directory of Open Access Journals (Sweden)

    Velojić-Golubović Milena

    2013-01-01

    Full Text Available Bacground/Aim. Visceral fat is highly active metabolic and endocrine tissue which secretes many adipokines that act both on local and systemic level. It is believed that adipokines and "low-grade inflammatory state" represent a potential link between obesity, metabolic syndrome, insulin resistance and cardiovascular disease. Leptin and adiponectin are considered to be the most important adipokines with the potential metabolic and cardiovascular effects. Body weight loss improves insulin sensitivity and decreases risk for most complications associated with obesity. The aim of this study was to determine the effects of moderate loss of body weight on the level of leptin and adiponectin, insulin sensitivity and abnormalities of glycoregulation in obese women, to determine whether and to what extent the secretory products of adipose tissue, leptin and adiponectin contribute to insulin sensitivity, as well as to assess their relationship and influence on glycemia and insulinemia during the period of losing body weight using a calorie restricted diet. Methods. The study involved 90 obese female subjects (BMI

  14. Global Metabolic Profiling of Plasma Shows that Three-Year Mild-Caloric Restriction Lessens an Age-Related Increase in Sphingomyelin and Reduces L-leucine and L-phenylalanine in Overweight and Obese Subjects.

    Science.gov (United States)

    Kim, Minjoo; Lee, Sang-Hyun; Lee, Jong Ho

    2016-12-01

    The effect of weight loss from long-term, mild-calorie diets (MCD) on plasma metabolites is unknown. This study was to examine whether MCD-induced weight reduction caused changes in the extended plasma metabolites. Overweight and obese subjects aged 40-59 years consumed a MCD (approximately 100 kcal/day deficit, n=47) or a weight-maintenance diet (control, n=47) in a randomized, controlled design with a three-year clinical intervention period and plasma samples were analyzed by using UPLC-LTQ-Orbitrap mass spectrometry. The three-year MCD intervention resulted in weight loss (-8.87%) and significant decreases in HOMA-IR and TG. The three-year follow-up of the MCD group showed reductions in the following 13 metabolites: L-leucine; L-phenylalanine; 9 lysoPCs; PC (18:0/20:4); and SM (d18:0/16:1). The three-year MCD group follow-up identified increases in palmitic amide, oleamide, and PC (18:2/18:2). Considering the age-related alterations in the identified metabolites, the MCD group showed a greater decrease in L-leucine, L-phenylalanine, and SM (d18:0/16:1) compared with those of the control group. Overall, the change (Δ) in BMI positively correlated with the ΔTG, ΔHOMA-IR, ΔL-leucine, and ΔSM (d18:0/16:1). The ΔHOMA-IR positively correlated with ΔTG, ΔL-leucine, ΔL-phenylalanine, and ΔSM (d18:0/16:1). The weight loss resulting from three-year mild-caloric restriction lessens the age-related increase in SM and reduces L-leucine and L-phenylalanine in overweight and obese subjects. These changes were coupled with improved insulin resistance (ClinicalTrials.gov: NCT02081898).

  15. Caloric restriction confers persistent anti-oxidative, pro-angiogenic, and anti-inflammatory effects and promotes anti-aging miRNA expression profile in cerebromicrovascular endothelial cells of aged rats.

    Science.gov (United States)

    Csiszar, Anna; Gautam, Tripti; Sosnowska, Danuta; Tarantini, Stefano; Banki, Eszter; Tucsek, Zsuzsanna; Toth, Peter; Losonczy, Gyorgy; Koller, Akos; Reglodi, Dora; Giles, Cory B; Wren, Jonathan D; Sonntag, William E; Ungvari, Zoltan

    2014-08-01

    In rodents, moderate caloric restriction (CR) without malnutrition exerts significant cerebrovascular protective effects, improving cortical microvascular density and endothelium-dependent vasodilation, but the underlying cellular mechanisms remain elusive. To elucidate the persisting effects of CR on cerebromicrovascular endothelial cells (CMVECs), primary CMVECs were isolated from young (3 mo old) and aged (24 mo old) ad libitum-fed and aged CR F344xBN rats. We found an age-related increase in cellular and mitochondrial oxidative stress, which is prevented by CR. Expression and transcriptional activity of Nrf2 are both significantly reduced in aged CMVECs, whereas CR prevents age-related Nrf2 dysfunction. Expression of miR-144 was upregulated in aged CMVECs, and overexpression of miR-144 significantly decreased expression of Nrf2 in cells derived from both young animals and aged CR rats. Overexpression of a miR-144 antagomir in aged CMVECs significantly decreases expression of miR-144 and upregulates Nrf2. We found that CR prevents age-related impairment of angiogenic processes, including cell proliferation, adhesion to collagen, and formation of capillary-like structures and inhibits apoptosis in CMVECs. CR also exerts significant anti-inflammatory effects, preventing age-related increases in the transcriptional activity of NF-κB and age-associated pro-inflammatory shift in the endothelial secretome. Characterization of CR-induced changes in miRNA expression suggests that they likely affect several critical functions in endothelial cell homeostasis. The predicted regulatory effects of CR-related differentially expressed miRNAs in aged CMVECs are consistent with the anti-aging endothelial effects of CR observed in vivo. Collectively, we find that CR confers persisting anti-oxidative, pro-angiogenic, and anti-inflammatory cellular effects, preserving a youthful phenotype in rat cerebromicrovascular endothelial cells, suggesting that through these effects CR may

  16. 运动与限食对雄性肥胖大鼠血清睾酮的影响%Effect of Exercise and Caloric Restriction on Plasma Testosterone in Obese Male Rats

    Institute of Scientific and Technical Information of China (English)

    楼晓娟; 李松波; 张爱芳; 汪毅

    2011-01-01

    目的:探讨运动与限食干预对青年雄性肥胖大鼠血清睾酮的影响。方法:采用双因素析因实验设计,肥胖模型建立后将肥胖大鼠按体重随机分为限食组、运动组、运动限食组、肥胖安静对照组。各组继续喂食高脂饲料,限食组喂食量为对照组喂食量的80%。游泳运动,5周,6 d/周,90 min/d。最后一次运动结束后60 min宰杀大鼠,分离血清测定睾酮。结果:1)对体重的影响:运动、限食主效应显著(P〈0.001或0.01),交互作用不显著(P〉0.05)。2)对大鼠血清睾酮的影响:运动与限食交互作用显著(P〈0.01)。结论:%Objective:This study was carried out to investigate the effects of swimming and caloric restriction on plasma testosterone in obese male rats.Methods: After the models of obesity were prepared successfully,those fat rats were randomized to four groups:cal

  17. Caloric restriction-associated remodeling of rat white adipose tissue: effects on the growth hormone/insulin-like growth factor-1 axis, sterol regulatory element binding protein-1, and macrophage infiltration.

    Science.gov (United States)

    Chujo, Yoshikazu; Fujii, Namiki; Okita, Naoyuki; Konishi, Tomokazu; Narita, Takumi; Yamada, Atsushi; Haruyama, Yushi; Tashiro, Kosuke; Chiba, Takuya; Shimokawa, Isao; Higami, Yoshikazu

    2013-08-01

    The role of the growth hormone (GH)-insulin-like growth factor (IGF)-1 axis in the lifelong caloric restriction (CR)-associated remodeling of white adipose tissue (WAT), adipocyte size, and gene expression profiles was explored in this study. We analyzed the WAT morphology of 6-7-month-old wild-type Wistar rats fed ad libitum (WdAL) or subjected to CR (WdCR), and of heterozygous transgenic dwarf rats bearing an anti-sense GH transgene fed ad libitum (TgAL) or subjected to CR (TgCR). Although less effective in TgAL, the adipocyte size was significantly reduced in WdCR compared with WdAL. This CR effect was blunted in Tg rats. We also used high-density oligonucleotide microarrays to examine the gene expression profile of WAT of WdAL, WdCR, and TgAL rats. The gene expression profile of WdCR, but not TgAL, differed greatly from that of WdAL. The gene clusters with the largest changes induced by CR but not by Tg were genes involved in lipid biosynthesis and inflammation, particularly sterol regulatory element binding proteins (SREBPs)-regulated and macrophage-related genes, respectively. Real-time reverse-transcription polymerase chain reaction analysis confirmed that the expression of SREBP-1 and its downstream targets was upregulated, whereas the macrophage-related genes were downregulated in WdCR, but not in TgAL. In addition, CR affected the gene expression profile of Tg rats similarly to wild-type rats. Our findings suggest that CR-associated remodeling of WAT, which involves SREBP-1-mediated transcriptional activation and suppression of macrophage infiltration, is regulated in a GH-IGF-1-independent manner.

  18. Short-term caloric restriction, resveratrol, or combined treatment regimens initiated in late-life alter mitochondrial protein expression profiles in a fiber-type specific manner in aged animals.

    Science.gov (United States)

    Joseph, Anna-Maria; Malamo, Angelina G; Silvestre, Jason; Wawrzyniak, Nick; Carey-Love, Sean; Nguyen, Linda M-D; Dutta, Debapriya; Xu, Jinze; Leeuwenburgh, Christiaan; Adhihetty, Peter J

    2013-09-01

    Aging is associated with a loss in muscle known as sarcopenia that is partially attributed to apoptosis. In aging rodents, caloric restriction (CR) increases health and longevity by improving mitochondrial function and the polyphenol resveratrol (RSV) has been reported to have similar benefits. In the present study, we investigated the potential efficacy of using short-term (6 weeks) CR (20%), RSV (50 mg/kg/day), or combined CR+ RSV (20% CR and 50 mg/kg/day RSV), initiated at late-life (27 months) to protect muscle against sarcopenia by altering mitochondrial function, biogenesis, content, and apoptotic signaling in both glycolytic white and oxidative red gastrocnemius muscle (WG and RG, respectively) of male Fischer 344 × Brown Norway rats. CR but not RSV attenuated the age-associated loss of muscle mass in both mixed gastrocnemius and soleus muscle, while combined treatment (CR + RSV) paradigms showed a protective effect in the soleus and plantaris muscle (P < 0.05). Sirt1 protein content was increased by 2.6-fold (P < 0.05) in WG but not RG muscle with RSV treatment, while CR or CR + RSV had no effect. PGC-1α levels were higher (2-fold) in the WG from CR-treated animals (P < 0.05) when compared to ad-libitum (AL) animals but no differences were observed in the RG with any treatment. Levels of the anti-apoptotic protein Bcl-2 were significantly higher (1.6-fold) in the WG muscle of RSV and CR + RSV groups compared to AL (P < 0.05) but tended to occur coincident with elevations in the pro-apoptotic protein Bax so that the apoptotic susceptibility as indicated by the Bax to Bcl-2 ratio was unchanged. There were no alterations in DNA fragmentation with any treatment in muscle from older animals. Additionally, mitochondrial respiration measured in permeabilized muscle fibers was unchanged in any treatment group and this paralleled the lack of change in cytochrome c oxidase (COX) activity. These data suggest that short-term moderate CR, RSV, or CR + RSV tended to

  19. The curve shortening problem

    CERN Document Server

    Chou, Kai-Seng

    2001-01-01

    Although research in curve shortening flow has been very active for nearly 20 years, the results of those efforts have remained scattered throughout the literature. For the first time, The Curve Shortening Problem collects and illuminates those results in a comprehensive, rigorous, and self-contained account of the fundamental results.The authors present a complete treatment of the Gage-Hamilton theorem, a clear, detailed exposition of Grayson''s convexity theorem, a systematic discussion of invariant solutions, applications to the existence of simple closed geodesics on a surface, and a new, almost convexity theorem for the generalized curve shortening problem.Many questions regarding curve shortening remain outstanding. With its careful exposition and complete guide to the literature, The Curve Shortening Problem provides not only an outstanding starting point for graduate students and new investigations, but a superb reference that presents intriguing new results for those already active in the field.

  20. 热量限制对SH-SY5Y细胞氧化损伤的影响%Effect of Caloric Restriction on Oxidative Damage in Human Neuroblastoma Cell Line SH-SY5Y Cells

    Institute of Scientific and Technical Information of China (English)

    陈娟; 张景燕; 王蓉; 赵静姝; 郭瑾; 吴燕川; 赵志炜

    2012-01-01

    Objective To observe the effect of caloric restriction on oxidative damage in human neuroblastoma cell line SH-SY5Y cells in vitro. Methods To establish an in vitro model of H2O2-induced oiidative stress damage of SH-SY5Y cells. SH-SY5Y cells were cultured in vitro. The cells were divided into four groups: control group, H2O2 (250μmol/L) group, low glucose (2g/L) group, and low glucose + H2 O2 group. Cell morphology, thiazolyl blue (MTT) metabolism rate, and lactate dehydrogenase (LDH) leakage rate were measured to observe the cell growth status in different groups. Results Compared with the control group, the MTT metabolism rate in the cells treated with 50 μmol/L H2O2 for one hour was not significantly changed (P >0. 05) , but it was significantly decreased in the 100, 250, 500, 1000 μmol/ L H202-treated groups than that of control group (P 0. 05) . The LDH leakage rate of the low glucose + H202group cultured for 7 hours was slightly higher than that of cells cultured for 1 hour (P >0. 05) . The histological observation revealed that the morphology of cells treated with low glucose was similar to that of the control group, and it was similar at one hour after H202 added. At 7 hours after addition of H202, the cells of the low glucose group and control group had well streching cytoplasmic projections, but in the H202 group, the cell number was significantly reduced, with a lot of dead cells, and the cells became rounded in shape and with poor adherence and transparence. Conclusion Caloric restriction can improve the viability and anti-oxidative stress ability of neurons, and reduce the cell mortality.%目的 观察热量限制培养条件下,SH-SY5Y细胞抗氧化应激损伤的能力.方法 建立过氧化氢诱导的SH-SY5Y细胞损伤模型.体外培养SH-SY5Y细胞,分为对照组、损伤组(50、100、250、500、1 000 μmol/L H2O2)、低糖组(2 g/L)、低糖+损伤组,进行细胞形态观察、测定各组细胞的噻唑蓝(MTT)代谢率、乳

  1. The Comparative Study of Skeletal Muscle Mitochondrial Oxidation and Antioxidant Levels in Aged Rats by Endurance Training and Caloric Restriction%耐力训练及限食对老龄大鼠骨骼肌线粒体氧化及抗氧化水平影响的比较研究

    Institute of Scientific and Technical Information of China (English)

    曾正中; 文立; 郝俊琴; 吴志义; 张勇

    2014-01-01

    Objective:We observed in aged rats with long -term endurance training and caloric restriction on skeletal muscle mitochondrial oxidation and antioxidant levels , and compare their individual and synergy effect , to provide certain theoretical basis for the theory “mitochondrial aging”.Methods:32 adult male 17month old SD rats were divided into 4 equal groups:control, caloric-restricted, exercise, exercise and caloric-restricted.Ex-ercise and caloric-restricted groups were trained for 12 months by running on a treadmill (64%VO2max;15 m/min, 60 min/day;5 days/week), while caloric-restricted group were maintained on 60%caloric intake of nor-mal caloric intake for 12 months.Measuring mitochondrial oxidative damage and antioxidant levels in rat skeletal muscle after the last training of 12 weeks.Results:the malondialdehyde (MDA) content in decreased significant-ly (P<0.05), Manganese superoxide dismutase (manganese -containing superoxide dismutase , MnSOD) ac-tivity increased significantly(P<0.05) and glutathione peroxidase (glutathion peroxidase, gsh-px) activity in-creased significantly(P<0.05) in CR group,E and CR +E group skeletal muscle mitochondria.The hydrogen peroxide enzyme (catalase, CAT) activity increased significantly (P<0.05) in E and CR +E group skeletal muscle mitochondria .Conclusions:On the one hand, endurance training improves the body ’ s antioxidant ability , on the other hand , endurance training saves cell function and declines oxygen consumption relatively and reduces the production of free radicals .CR weakens the oxidative stress and reduces the production of free radicals and prevents the lipid peroxidation .while CR mobilizes a series of adaptive network defense mechanism and increases antioxidant levels and strengthens the defense .Endurance exercise is significant stronger than the effect of caloric restriction on the antioxidant ability .The synergy of endurance training and CR is stronger than the effect of their individual effects

  2. A Comparative Study of Endurance Training and Caloric Restriction on Mitochondrial Respiratory Function in Skeletal Muscle of the Aged Rats%耐力训练及限食对老龄大鼠骨骼肌线粒体呼吸功能影响的比较研究

    Institute of Scientific and Technical Information of China (English)

    曾正中; 文立; 郝俊琴; 吴志义; 张勇

    2014-01-01

    Objective:we observe the long -term effects of endurance training and diet restriction on skeletal muscle mitochondrial function in aging rats,comparing their individual and synergistic effects of endurance training and diet restriction,investigating mitochondrial mechanism.Method32 adult male 17month old SD rats were divided into 4 equal groupcontrol,caloric -restricted,exercise,exercise and caloric -restricted. Exercise and exercise and caloric-restricted groups were trained for 12months by running on a treadmill (64%VO2max;15 m/min,60 min/day;5 days/week ),while caloric -restricted group were maintained on 60%caloric intake of normal caloric intake for 12months.Measuring mitochondrial respiratory function in rat skeletal muscle after the last training of 12 weeks.ResultState3respirationCRgroup and CR +E group was significantly lower,E group were significantly higher(P <0.05);State4respirationCRgroup was significantly reduce(P <0.05),E group and CR +E no significant change;Respiratory control ratio was significantly lower in the CR group and CR +E group,E significantly increased(P<0.05 );ATP synthesis activity was significant increase in group E (P <0.05 ),while the CR group and CR +E group had no significant change.ConclusionEndurance training improves the efficiency of electron transfer in rat skeletal muscle mitochondrial respiratory chain,improving mitochondrial respiratory function,and enhancing the ability of oxidative phosphorylation, reducing the demand for energy restricted diet,reducing the efficiency of mitochondrial oxidative phosphorylation.%目的:观察长期耐力训练及限食对老龄大鼠骨骼肌线粒体功能的影响,比较其单独及协同作用,探讨耐力训练及限食的线粒体机制。方法:32只17月龄雄性SD大鼠分为4组:安静组(Control,C)、限食组(Caloric-Restricted,CR)、运动组(Exercise,E)和限食加运动组(Caloric-restricted and Exercise,E+CR),训练方式为跑台

  3. Influence of caloric intake on experimental carcinogenesis: a review.

    Science.gov (United States)

    Kritchevsky, D; Klurfeld, D M

    1986-01-01

    The effect of caloric intake on tumor growth has been recognized for over 70 years. Inhibition of tumor growth depends primarily on the extent of caloric restriction, but tumor type, animal strain, and dietary composition all exert some influence. Caloric restriction is most effective when maintained during both initiation and promotion, but if limited to one of these phases, restriction during promotion appears to be the more effective modality. The types of tumor that have been studied include spontaneous mammary and lung tumors as well as tumors induced by organ-specific carcinogens or irradiation with ultraviolet light. Numerous investigators have studied the effects of fat, and a diet low in calories but high in fat is generally significantly more effective in inhibiting carcinogenesis than is a diet high in calories but low in fat. Mice fed high fat, low calorie diets exhibited 48% fewer chemically induced skin tumors and 61% fewer tumors induced by ultraviolet irradiation than did mice fed low fat, high calorie diets. Mice fed a diet containing 2% fat exhibited a 66% incidence of skin tumors, whereas mice fed an isocaloric diet containing 61% fat showed a 78% incidence. Rats whose diet was restricted in calories by 40% exhibited no mammary tumors (coconut oil as primary dietary fat) or 75% fewer tumors (corn oil as dietary fat) compared to ad libitum-fed controls; they also exhibited 47% fewer colonic tumors. The mechanism by which caloric restriction exerts its tumor-inhibiting effects remains to be elucidated.

  4. Systematic review and meta-analysis reveals acutely elevated plasma cortisol following fasting but not less severe calorie restriction

    OpenAIRE

    Nakamura, Yuko; Walker, Brian R; Ikuta, Toshikazu

    2016-01-01

    Elevated plasma cortisol has been reported following caloric restriction, and may contribute to adverse effects including stress-induced overeating, but results from published studies are inconsistent. To clarify the effects of caloric restriction on plasma cortisol, and to assess cortisol as an indicator of stress during caloric restriction, we conducted a systematic review and meta-analysis of published studies in which cortisol was measured following caloric restriction without other manip...

  5. 药理模拟实现限食健康优势的研究进展%Research progress on pharmacological mimic in beneficial effects of caloric restriction

    Institute of Scientific and Technical Information of China (English)

    华卫国; 沈晓东; 储维忠

    2007-01-01

    限食(Dietary Caloric Restriction,DR/CR),指的是每日摄食量的减少,处于低营养水平(undernutrition)而非营养不良(malnutrition)。一般认为限食的本质在于保障蛋白质和必需营养素前提下,限制热量摄入。由限食/热量限制而产生的健康维护和促进作用,称之为限食健康优势(beneficial effects of CR)。早在20世纪的前半叶就有人发现,限制鼠类的日进食量可以防治肿瘤(Moreschi,1909)和延缓衰老(McCay,1935)。随后,CR现象引起了这两个研究领域的广泛兴趣和数个研究热潮。

  6. Comparison of standardized versus individualized caloric prescriptions in the nutritional rehabilitation of inpatients with anorexia nervosa

    Science.gov (United States)

    Haynos, Ann F.; Snipes, Cassandra; Guarda, Angela; Mayer, Laurel E.; Attia, Evelyn

    2015-01-01

    Objective Sparse research informs how caloric prescriptions should be advanced during nutritional rehabilitation of inpatients with anorexia nervosa (AN). This study compared the impact of a standardized caloric increase approach, in which increases occurred on a predetermined schedule, to an individualized approach, in which increases occurred only following insufficient weight gain, on rate, pattern, and cumulative amount of weight gain and other weight restoration outcomes. Method This study followed a natural experiment design comparing AN inpatients consecutively admitted before (n = 35) and after (n = 35) an institutional change from individualized to standardized caloric prescriptions. Authors examined the impact of prescription plan on weekly weight gain in the first treatment month using multilevel modeling. Within a subsample remaining inpatient through weight restoration (n = 40), multiple regressions examined the impact of caloric prescription plan on time to weight restoration, length of hospitalization, maximum caloric prescription, discharge BMI, and incidence of activity restriction and edema. Results There were significant interactions between prescription plan and quadratic time on average weekly weight gain (p = .03) and linear time on cumulative weekly weight gain (p < .001). Under the standardized plan, patients gained in an accelerated curvilinear pattern (p = .04) and, therefore, gained cumulatively greater amounts of weight over time (p < .001). Additionally, 30% fewer patients required activity restriction under the standardized plan. Discussion Standardized caloric prescriptions may confer advantage by facilitating accelerated early weight gain and lower incidence of bed rest without increasing the incidence of refeeding syndrome. PMID:26769581

  7. Oleoyl-estrone metabolic effects in relation with caloric restriction in inbred Beta rats with spontaneous obesity and type 2 diabetes Efectos metabólicos de la oleoil-estrona en relación con la restricción calórica en ratas Beta endocriadas, con obesidad espontánea y diabetes tipo II

    Directory of Open Access Journals (Sweden)

    Marta D. Posadas

    2004-08-01

    Full Text Available Spontaneously hypertriacylglycerolemic obese and diabetic inbred IIM Beta rats were treated with oleoyl- estrone for 10 days. Pair-feeding was performed to determine some oleoyl-estrone effects dependent on the caloric restriction it promotes. Twenty-five 200 day-old Beta males receiving a daily gavage of 0.2 ml sunflower oil were divided into the following groups: 1 daily dose of 10 nmol/g oleoyl-estrone; 2 pair-fed; 3 control. The variables measured were: whole body protein, water and lipid; retroperitoneal and epididymal fat depot weights; plasma urea, glucose, insulin, triacylglycerols and cholesterol. Biomass and food intake were assessed daily. Oleoyl-estrone and pair-fed groups expressed similar variations in body composition and significant body weight losses due to reduction in food intake. Oleoyl-estrone and pair-fed treatments significantly reduced retroperitoneal fat depot weights, but not epididymal ones. In oleoyl-estrone and pair-fed groups hyperglycemia decreased and insulinemia lowered significantly. Plasma normal total cholesterolemia and hypertriacylglycerolemia values typical of Beta rats decreased strongly compared to controls, though attaining significantly different values between oleoyl-estrone and pair-fed groups. Plasma total cholesterol appeared as more sensitive to caloric restriction than triacylglycerols through a specific oleoyl-estrone- mediated effect.Ratas endocriadas de la línea IIMBeta con obesidad, hipertriacilglicerolemia y diabetes espontáneas fueron tratadas con oleoil-estrona durante 10 días. Un grupo con restricción alimentaria fue incluido en el estudio a fin de aislar algunos efectos de la oleoil-estrona dependientes de la restricción calórica que ésta promueve. Veinticinco ratas Beta macho de 200 días de edad a los que se suministró 0.2 ml de aceite de girasol por día se dividieron en los siguientes grupos: (1 dosis diaria de 10 nmol/g de oleoil-estrona; (2 restringido; (3 control. Las

  8. Carnot to Clausius: Caloric to Entropy

    Science.gov (United States)

    Newburgh, Ronald

    2009-01-01

    This paper discusses how the Carnot engine led to the formulation of the second law of thermodynamics and entropy. The operation of the engine is analysed both in terms of heat as the caloric fluid and heat as a form of energy. A keystone of Carnot's thinking was the absolute conservation of caloric. Although the Carnot analysis was partly…

  9. Drunkorexia: Calorie Restriction Prior to Alcohol Consumption among College Freshman

    Science.gov (United States)

    Burke, Sloane C.; Cremeens, Jennifer; Vail-Smith, Karen; Woolsey, Conrad

    2010-01-01

    Using a sample of 692 freshmen at a southeastern university, this study examined caloric restriction among students prior to planned alcohol consumption. Participants were surveyed for self-reported alcohol consumption, binge drinking, and caloric intake habits prior to drinking episodes. Results indicated that 99 of 695 (14%) of first year…

  10. Caloric curve of star clusters.

    Science.gov (United States)

    Casetti, Lapo; Nardini, Cesare

    2012-06-01

    Self-gravitating systems, such as globular clusters or elliptical galaxies, are the prototypes of many-body systems with long-range interactions, and should be the natural arena in which to test theoretical predictions on the statistical behavior of long-range-interacting systems. Systems of classical self-gravitating particles can be studied with the standard tools of equilibrium statistical mechanics, provided the potential is regularized at small length scales and the system is confined in a box. The confinement condition looks rather unphysical in general, so that it is natural to ask whether what we learn with these studies is relevant to real self-gravitating systems. In order to provide an answer to this question, we consider a basic, simple, yet effective model of globular clusters: the King model. This model describes a self-consistently confined system, without the need of any external box, but the stationary state is a nonthermal one. In particular, we consider the King model with a short-distance cutoff on the interactions, and we discuss how such a cutoff affects the caloric curve, i.e., the relation between temperature and energy. We find that the cutoff stabilizes a low-energy phase, which is absent in the King model without cutoff; the caloric curve of the model with cutoff turns out to be very similar to that of previously studied confined and regularized models, but for the absence of a high-energy gaslike phase. We briefly discuss the possible phenomenological as well as theoretical implications of these results.

  11. Fasting leptin and appetite responses induced by a 4-day 65%-energy-restricted diet

    NARCIS (Netherlands)

    Mars, M.; Graaf, de C.; Groot, de C.P.G.M.; Rossum, van C.T.M.; Kok, F.J.

    2006-01-01

    Objective: Animal studies show that the leptin decline after acute severe caloric restriction is a peripheral signal to increase food intake. However, most human studies have failed to observe such a relationship. We studied the acute effects of severe caloric restriction on the association between

  12. Fasting leptin and appetite responses induced by a 4-day 65%-energy-restricted diet.

    NARCIS (Netherlands)

    Mars, M; Graaf, C de; Groot, C P G M de; Rossum, Caroline T M van; Kok, F J

    2006-01-01

    OBJECTIVE: Animal studies show that the leptin decline after acute severe caloric restriction is a peripheral signal to increase food intake. However, most human studies have failed to observe such a relationship. We studied the acute effects of severe caloric restriction on the association between

  13. Caloric beverage consumption patterns in Mexican children

    Directory of Open Access Journals (Sweden)

    Rivera Juan A

    2010-10-01

    Full Text Available Abstract Background Mexico has seen a very steep increase in child obesity level. Little is known about caloric beverage intake in this country as well as all other countries outside a few high income countries. This study examines overall patterns and trends in all caloric beverages from two nationally representative surveys from Mexico. Methods The two nationally representative dietary intake surveys (1999 and 2006 from Mexico are used to study caloric beverage intake in 17, 215 children. The volume (ml and caloric energy (kcal contributed by all beverages consumed by the sample subjects were measured. Results are weighted to be nationally representative. Results The trends from the dietary intake surveys showed very large increases in caloric beverages among pre-school and school children. The contribution of whole milk and sugar-sweetened juices was an important finding. Mexican pre-school children consumed 27.8% of their energy from caloric beverages in 2006 and school children consumed 20.7% of their energy from caloric beverages during the same time. The three major categories of beverage intake are whole milk, fruit juice with various sugar and water combinations and carbonated and noncarbonated sugared-beverages. Conclusion The Mexican government, greatly concerned about obesity, has identified the large increase in caloric beverages from whole milk, juices and soft drinks as a key target and is initiating major changes to address this problem. They have already used the data to shift 20 million persons in their welfare and feeding programs from whole to 1.5% fat milk and in a year will shift to nonfat milk. They are using these data to revise school beverage policies and national regulations and taxation policies related to an array of less healthful caloric beverages.

  14. Intake of calorically sweetened beverages and obesity

    DEFF Research Database (Denmark)

    Olsen, N J; Heitmann, B L

    2009-01-01

    The prevalence of obesity has increased in the past 30 years, and at the same time a steep increase in consumption of soft drinks has been seen. This paper reviews the literature for studies on associations between intake of calorically sweetened beverages and obesity, relative to adjustment...... studies were identified. The majority of the prospective studies found positive associations between intake of calorically sweetened beverages and obesity. Three experimental studies found positive effects of calorically sweetened beverages and subsequent changes in body fat. Two experimental studies did...... not find effects. Eight prospective studies adjusted for energy intake. Seven of these studies reported associations that were essentially similar before and after energy adjustment. In conclusion, a high intake of calorically sweetened beverages can be regarded as a determinant for obesity. However...

  15. Uma medida de calor específico sem calorímetro

    Directory of Open Access Journals (Sweden)

    Mattos Cristiano

    2003-01-01

    Full Text Available Várias técnicas têm sido desenvolvidas para se obter o calor específico de sólidos e líquidos, incluindo a construção de experimentos de baixo custo para o ensino médio. Neste trabalho propomos uma maneira simples de se obter o calor específico de sólidos e líquidos. Por meio de curvas de calibração de resfriamento podemos estimar graficamente a perda de calor do sistema para sua vizinhança, e medir o calor específico do alumínio. Esta aproximação permite introduzir uma discussão sobre o processo dinâmico da troca de calor entre dos corpos.

  16. Shortening Anomalies in Supersymmetric Theories

    CERN Document Server

    Gomis, Jaume; Ooguri, Hirosi; Seiberg, Nathan; Wang, Yifan

    2016-01-01

    We present new anomalies in two-dimensional ${\\mathcal N} =(2, 2)$ superconformal theories. They obstruct the shortening conditions of chiral and twisted chiral multiplets at coincident points. This implies that marginal couplings cannot be promoted to background super-fields in short representations. Therefore, standard results that follow from ${\\mathcal N} =(2, 2)$ spurion analysis are invalidated. These anomalies appear only if supersymmetry is enhanced beyond ${\\mathcal N} =(2, 2)$. These anomalies explain why the conformal manifolds of the K3 and $T^4$ sigma models are not K\\"ahler and do not factorize into chiral and twisted chiral moduli spaces and why there are no ${\\mathcal N} =(2, 2)$ gauged linear sigma models that cover these conformal manifolds. We also present these results from the point of view of the Riemann curvature of conformal manifolds.

  17. T2 shortening in childhood moyamoya disease

    Energy Technology Data Exchange (ETDEWEB)

    Takanashi, J. [Department of Pediatrics, Faculty of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi 260 (Japan); Sugita, K. [Department of Pediatrics, Faculty of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi 260 (Japan); Tanabe, Y. [Division of Neurology, Chiba Children`s Hospital, 579-1 Heta, Midori-ku, Chiba-shi 266 (Japan); Ito, C. [Division of Neurosurgery, Chiba Children`s Hospital, 579-1 Heta, Midori-ku, Chiba-shi 266 (Japan); Date, H. [Division of Neurosurgery, Chiba Children`s Hospital, 579-1 Heta, Midori-ku, Chiba-shi 266 (Japan); Niimi, H. [Department of Pediatrics, Faculty of Medicine, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba-shi 260 (Japan)

    1996-05-01

    We examined T2 shortening in six children with infarcts due to moyamoya disease to clarify whether there are characteristic patterns of T2 shortening in the deep grey and white matter. Profound T2 shortening in the deep grey and white matter was observed in the acute stage of infarct in two cases, which changed to high intensity in the chronic stage; in this stage no T2 shortening was demonstrated in any case. Neither haemorrhagic infarction nor calcification was seen on CT or MRI. There could be longitudinally different T2 shortening patterns between infarcts due to moyamoya disease and other disorders. (orig.). With 2 figs., 1 tab.

  18. Telomere shortening may be associated with human keloids

    Directory of Open Access Journals (Sweden)

    Wilson Robert R

    2009-10-01

    Full Text Available Abstract Background Keloids are benign skin tumors that are the effect of a dysregulated wound-healing process in genetically predisposed patients. They are inherited with an autosomal dominant mode with incomplete clinical penetrance and variable expression. Keloids are characterized by formation of excess scar tissue beyond the boundaries of the wound. The exact etiology is still unknown and there is currently no appropriate treatment for keloid disease. Methods We analyzed sample tissues were obtained from 20 patients with keloid skin lesions and normal skin was obtained from 20 healthy donors. The telomeres were measured by Terminal Restriction Fragment (TRF analysis and Real-Time PCR assay. Quantitative Real-Time RT-PCR analysis of hTERT gene expression was performed and intracellular ROS generation was measured. Results In this study, we determined whether telomeric shortening and the expression of human telomerase reverse transcriptase (hTERT occurs in keloid patients. Using Terminal Restriction Fragment (TRF analysis and Real-Time PCR assay, we detected a significant telomere shortening of 30% in keloid specimens compared to normal skin. Using quantitative Real-Time RT-PCR, telomerase activity was found absent in the keloid tissues. Moreover, an increase in ROS generation was detected in fibroblasts cell cultures from keloid specimens as more time elapsed compared to fibroblasts from normal skin. Conclusion Telomere shortening has been reported in several metabolic and cardiovascular diseases. We found that telomere shortening can also be associated with human keloids. Chronic oxidative stress plays a major role in the pathophysiology of several chronic inflammatory diseases. Here we found increased ROS generation in fibroblasts from keloid fibroblasts cell cultures when compared to normal skin fibroblasts. Hence we conclude that oxidative stress might be an important modulator of telomere loss in keloid because of the absence of active

  19. Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Cammarata, Paul; Hagel, Kris; Heilborn, Lauren; Kohley, Zachary; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2012-01-01

    A basic feature of the nuclear equation of state is not yet understood: the dependence of the nuclear caloric curve on the neutron-proton asymmetry. Predictions of theoretical models differ on the magnitude and even the sign of this dependence. In this work, the nuclear caloric curve is examined for fully reconstructed quasi-projectiles around mass A=50. The caloric curve extracted with the momentum quadrupole fluctuation thermometer shows that the temperature varies linearly with quasi-projectile asymmetry (N-Z)/A. An increase in asymmetry of 0.15 units corresponds to a decrease in temperature on the order of 1 MeV. These results also highlight the importance of a full quasi-projectile reconstruction in the study of thermodynamic properties of hot nuclei.

  20. New developments in caloric materials for cooling applications

    Science.gov (United States)

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-06-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  1. New developments in caloric materials for cooling applications

    OpenAIRE

    Crossley, S.; Mathur, N. D.; Moya, X.

    2015-01-01

    Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric) effects.

  2. 10 CFR 590.316 - Shortened proceedings.

    Science.gov (United States)

    2010-01-01

    ... 10 Energy 4 2010-01-01 2010-01-01 false Shortened proceedings. 590.316 Section 590.316 Energy... WITH RESPECT TO THE IMPORT AND EXPORT OF NATURAL GAS Procedures § 590.316 Shortened proceedings. In any proceeding where, in response to a notice of application or notice of procedures, if applicable, no...

  3. Effect of short-term caloric restriction on the secretion of gastrointestinal and adipose-derived hormones in patients with metabolic syndrome%短期限食对代谢综合征患者胃肠激素及脂肪分泌激素的影响

    Institute of Scientific and Technical Information of China (English)

    陈国芳; 李春睿; 茅晓东; 范尧夫; 程清; 相小多; 陈杰; 徐书杭; 狄红杰

    2015-01-01

    Objective To investigate the effect of short-term severe caloric restriction (SCR) on the secretion of gastrointestinal and adipose-derived hormones in patients with metabolic syndrome.Method Eight patients with metabolic syndrome received SCR for 9 days.Anthropometric and biochemical parameters were determined before and after SCR.Results After short-term SCR,the average body weight was decreased from (84.46 ± 18.21) kg to (80.10 ± 17.43) kg (P<0.01),waist circumference reduced from (99.88 ± 12.12) cm to (95.81 ± 11.82) cm (P< 0.01),and body mass index decreased from (29.56 ± 4.16) kg/m2 to (28.03 ± 4.01) kg/m2 (P<0.01).Blood pressure,fasting triglycerides,fasting blood glucose,fasting insulin,and homeostasis model assessment for insulin resistance were all reduced significantly after SCR,while no differences were found in serum cholesterol,low density lipoprotein-cholesterol,and high density lipoprotein-cholesterol.The level of insulin-like growth factor-Ⅰ (IGF-Ⅰ) was decreased from (144.50 ± 44.12) ng/ml to (108.30 ± 43.01) ng/ml (P =0.007 4).Among hormones related to energy regulation,the levels of amylin and leptin were reduced from (35.46 ± 5.99) pg/ml to (16.23 ± 5.24) pg/ml (P=0.000 4) and from (12 390 ± 2 415) pg/ml to (7 191 ± 2 083) pg/ml (P =0.007 7) after SCR,respectively.However,there was no significant difference in ghrelin,gastric inhibitory polypeptide,GLP-1,and adiponectin before and after SCR.Conclusions Short-term SCR improved metabolic markers in patients with metabolic syndrome.The changes in hormones related to energy regulation induced by SCR could be involved in the mechanism.%目的 探讨短期极低热量限食对代谢综合征患者胃肠激素及脂肪分泌激素的影响.方法 对8例代谢综合征患者行住院9d极低热量限食(300 ~ 600 kcal/d),测量限食前后体重、腰围、血压;检测限食前后空腹血糖、血脂、胰岛素、胰岛素样生长因子Ⅰ (IGF-Ⅰ)、胰淀素、胃促生

  4. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos por calor. Este método permite destruír ...

  5. Transferencia de calor a lechos empacados

    OpenAIRE

    Beltrán Feged, Alvaro; Bonilla Melendez, Alberto; Cancelado Arias, Miguel

    2012-01-01

    Consideremos el lecho de solidos granulados de la figura 1.El lecho esta a una temperatura u (z,t), y tiene un calor especifico  cs, que se toma constante. z es la altura del lecho, y t es el tiempo. A este lecho entran G unidades de masa de fluido por unidad de tiempo y de área de sección de lecho(1)(2)

  6. Child Abuse May Shorten Some Women's Lives

    Science.gov (United States)

    ... page: https://medlineplus.gov/news/fullstory_160478.html Child Abuse May Shorten Some Women's Lives Extreme stress may ... 300 middle-aged U.S. adults, female survivors of child abuse were more likely to die over the next ...

  7. Fasting leptin and appetite responses induced by a 4-day 65%-energy-restricted diet.

    OpenAIRE

    Mars, M; De Graaf, C.; de Groot, C. P. G. M.; Rossum, Caroline T M van; Kok, F.J.

    2006-01-01

    OBJECTIVE: Animal studies show that the leptin decline after acute severe caloric restriction is a peripheral signal to increase food intake. However, most human studies have failed to observe such a relationship. We studied the acute effects of severe caloric restriction on the association between serum leptin concentrations and subjective appetite. SUBJECTS: A total of 44 healthy adult men (aged: 43 +/- 5 years; BMI: 27.3 +/- 3.2 kg/m(2)). MEASUREMENTS: Fasting serum leptin concentrations a...

  8. Occlusal stability in shortened dental arches.

    Science.gov (United States)

    Witter, D J; Creugers, N H; Kreulen, C M; de Haan, A F

    2001-02-01

    Shortened dental arches consisting of anterior and premolar teeth have been shown to meet oral functional demands. However, the occlusal stability may be at risk as a result of tooth migration. The aim of this nine-year study was to investigate occlusal stability in shortened dental arches as a function over time. Occlusal stability indicators were: 'interdental spacing', 'occlusal contacts of anterior teeth in Intercuspal Position', 'overbite', 'occlusal tooth wear', and 'alveolar bone support'. Subjects with shortened dental arches (n = 74) were compared with subjects with complete dental arches (controls, n = 72). Repeated-measurement regression analyses were applied to assess age-dependent variables in the controls and to relate the occlusal changes to the period of time since the treatment that led to the shortened dental arches. Compared with complete dental arches, shortened dental arches had similar overbite and occlusal tooth wear. They showed more interdental spacing in the premolar regions, more anterior teeth in occlusal contact, and lower alveolar bone scores. Since the differences remained constant over time, we conclude that shortened dental arches can provide long-term occlusal stability. Occlusal changes were self-limiting, indicating a new occlusal equilibrium.

  9. Use of non-caloric edulcorants in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available We analyze the health normativity for the denomination of non caloric edulcorants in Mexico, and the authorization for the use of natural and synthetic non caloric edulcorants in newborn and until puberty. Special emphasis was given to the consecutive points of safety required in order to assure that they are free of secondary effects. For each non caloric edulcorant available in Mexico, we looked into the studies which mention their side effects in terms of growth and overall.

  10. A new light on caloric test--what was disclosed by three dimensional analysis of caloric nystagmus?

    Science.gov (United States)

    Arai, Y.

    2001-01-01

    For better understanding of caloric nystagmus, this phenomenon will be reviewed historically in three stages. 1) The first light on caloric nystagmus was thrown by Barany 1906. Through direct observation of eye movements, Barany established the caloric test as an important tool to determine the side of lesion for vertigo. 2) The second light is shed by electrooculogram (EOG) from the late 1950th. EOG enabled qualitative analysis of caloric nystagmus, and proved Barany's convection theory, but resulted in neglect of vertical and roll eye movements. 3) The third light is gained by 3D recording of eye movements started from the late 1980th. 3D recordings of eye movements enabled us to analyze the spatial orientation of caloric nystagmus, and disclose the close correlation of the nystagmus components in the head vertical and the space vertical planes, suggesting a contribution of the velocity storage integrator. The 3D property of caloric nystagmus will be explained in detail.

  11. Modeling microscale heat transfer using Calore.

    Energy Technology Data Exchange (ETDEWEB)

    Gallis, Michail A.; Rader, Daniel John; Wong, Chung-Nin Channy; Bainbridge, Bruce L.; Torczynski, John Robert; Piekos, Edward Stanley

    2005-09-01

    Modeling microscale heat transfer with the computational-heat-transfer code Calore is discussed. Microscale heat transfer problems differ from their macroscopic counterparts in that conductive heat transfer in both solid and gaseous materials may have important noncontinuum effects. In a solid material, three noncontinuum effects are considered: ballistic transport of phonons across a thin film, scattering of phonons from surface roughness at a gas-solid interface, and scattering of phonons from grain boundaries within the solid material. These processes are modeled for polycrystalline silicon, and the thermal-conductivity values predicted by these models are compared to experimental data. In a gaseous material, two noncontinuum effects are considered: ballistic transport of gas molecules across a thin gap and accommodation of gas molecules to solid conditions when reflecting from a solid surface. These processes are modeled for arbitrary gases by allowing the gas and solid temperatures across a gas-solid interface to differ: a finite heat transfer coefficient (contact conductance) is imposed at the gas-solid interface so that the temperature difference is proportional to the normal heat flux. In this approach, the behavior of gas in the bulk is not changed from behavior observed under macroscopic conditions. These models are implemented in Calore as user subroutines. The user subroutines reside within Sandia's Source Forge server, where they undergo version control and regression testing and are available to analysts needing these capabilities. A Calore simulation is presented that exercises these models for a heated microbeam separated from an ambient-temperature substrate by a thin gas-filled gap. Failure to use the noncontinuum heat transfer models for the solid and the gas causes the maximum temperature of the microbeam to be significantly underpredicted.

  12. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Directory of Open Access Journals (Sweden)

    Franco eDelogu

    2016-01-01

    Full Text Available Consumption of sugar-sweetened beverages (SSBs is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs. 55 college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices.

  13. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks’ sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers’ choices. PMID:26858681

  14. A Dissociation Between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks.

    Science.gov (United States)

    Delogu, Franco; Huddas, Claire; Steven, Katelyn; Hachem, Souheila; Lodhia, Luv; Fernandez, Ryan; Logerstedt, Macee

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms of sweetness and likeability. They were also asked to recognize, if the drinks contained sugar or a non-caloric artificial sweetener. Overall, participants showed poor accuracy in discriminating drinks' sweeteners, with significantly lower accuracy for SSBs than ASBs. Interestingly, we found a dissociation between sweetener recognition and drink pleasantness. In fact, in spite of a chance-level discrimination accuracy of SSBs, their taste was systematically preferred to the taste of non-caloric beverages. Our findings support the idea that hedonic value of carbonated soft drinks is dissociable from its identification and that the activation of the pleasure system seems not to require explicit recognition of the sweetener contained in the soft drink. We hypothesize that preference for carbonated soft drinks containing sugar over non-caloric alternatives might be modulated by metabolic factors that are independent from conscious and rational consumers' choices.

  15. Caloric versus low-caloric sweeteners: Can the body be fooled?

    NARCIS (Netherlands)

    Smeets, P.A.M.

    2010-01-01

    Low-caloric artificial sweeteners have been around for several decades now. Still, the debate over their usefulness in decreasing energy intake is ongoing. In principle, replacing sugar-containing foods with 'light' versions will lead to decreased energy intake. However, the reality of food intake b

  16. 热量限制联合心理引导及高压氧治疗协同改善胶质母细胞瘤患者预后的前瞻性研究%Perspective research of the influence of caloric restriction combined with psychotherapy and chemotherapy associated by hybaroxia on the prognosis of patients suffered by glioblastoma multiforme under total resection

    Institute of Scientific and Technical Information of China (English)

    韩利江; 张俊廷; 杜洪涛; 韩小弟; 李健; 张鹏飞

    2015-01-01

    VEGF阳性率越低,患者生存期越长;累及脑叶数量、年龄、性别对生存期无明显影响;术中应用卡莫司汀贴片和术后应用贝伐珠单抗不能延长GBM患者生存期.%Objective To investigated prognosis of caloric restriction combined with psychotherapy and hybaroxia chemotherapy in patients suffered by intracranial glioblastoma multiforme(GBM) under total resection.Methods Forty-five GBM patients from November 2007 to May 2011 were devided into control group(30cases) and test group(15cases).patients in underwent total resections,radiotherapies and chemotherapies (Temozolomide 150 mg/m2,5/28 day).Three VEGF positive patients were given Bevacizumab(5 mg/kg,once every two weeks,total 4 times),and two were given carmustine wafers covered on the bed of the tumor during the second surgery.Fifteen patients in were furthermore treated by caloric restriction combined with psychotherapy and chemotherapy (Temozolomide 150 mg/m2,5/28 day) associated by hybaroxia(CRPH).Two VEGF positive patients were given Bevacizumab(5 mg/kg,once every two weeks,total 4 times),and one was given carmustine wafers covered on the bed of the tumor during the second surgery.the influence of correlation factors on prognosis were analyzed.Results Overall survival were longer in control group than in test group [(35 ± 13)months vs(19 ± 11)months,P =0.000] ; caloric restriction combined with psychotherapy and hybaroxia chemotherapy werepositively correlated with operations and overall survival (r =0.559,P =0.000 ; r =0.313,P =0.036) ; survival were Negatively correlated with tumor size (r=-0.436,P =0.003) ;Ki-67 、MGMT、VEGFpositive rates were Negatively correlated with survival (r =-0.497、P =0.001 ; r =-0.377,P =0.011 ; r =-0.540,P =0.000) ; there were no association between age,sex,Tumor involving the number of lobes,tumor located in advantage hemisphere and survival(r =0.166,P =0.276,r =0.134,P =0.380 ; r =0.005,P =0.972 ; r =0.018,P =0.908) ; Carmustine wafers

  17. New developments in caloric materials for cooling applications

    Directory of Open Access Journals (Sweden)

    S. Crossley

    2015-06-01

    Full Text Available Caloric materials are in the spotlight as candidates for future environmentally friendly cooling technologies. We describe stimulating recent developments in the three caloric strands that are now being studied collectively, namely magnetocaloric, electrocaloric and mechanocaloric (elastocaloric or barocaloric effects.

  18. Numerical Simulation of Pulse Shortening in RBWOs

    Institute of Scientific and Technical Information of China (English)

    GONG Yu-bin; ZHANG Zhang; WANG Wen-xiang; MENG Fan-bao; FAN Zhi-kai; HUANG Min-zhi

    2005-01-01

    Pulse shortening hinders improvement of microwave output energy for high power microwave tubes. So far, it is also an unresolved problem in the field of high power microwave devices. In this paper, relativistic backward wave tube (RBWO) is treated as an example to study the pulse shortening phenomena. The influences of gas existing in the tube and explosive emission in inner surface of RBWO are all investigated by means of the particle-in-cell method. Through the simulation results, it can be predicted that the background gas in the tube is one but not the most important factor resulting in pulse shortening, in order to broaden the pulse width of gas-filled RBWO, the pressure of the filled gas must be controlled in a proper value. The explosive emission in the surface of slow wave structure due to intense electric field is one of the most important factors causing pulse shortening in high power microwave tube.Some methods to overcome this find of explosive emission are also given.

  19. 9 CFR 319.701 - Mixed fat shortening.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 2 2010-01-01 2010-01-01 false Mixed fat shortening. 319.701 Section... INSPECTION AND CERTIFICATION DEFINITIONS AND STANDARDS OF IDENTITY OR COMPOSITION Fats, Oils, Shortenings § 319.701 Mixed fat shortening. Shortening prepared with a mixture of meat fats and vegetable oils...

  20. Tetanic force potentiation of mouse fast muscle is shortening speed dependent.

    Science.gov (United States)

    Gittings, William; Huang, Jian; Vandenboom, Rene

    2012-10-01

    The activity dependent potentiation of peak isometric force associated with phosphorylation of the myosin regulatory light chain (RLC) is generally restricted to low activation frequencies. The purpose of this study was to determine if muscle shortening speed influenced the stimulus frequency domain over which concentric force potentiation was observed. To this end, mouse extensor digitorum longus (EDL) muscles (in vitro, 25 °C) were activated at a range of test frequencies (10, 25, 45, 70 or 100 Hz) during shortening ramps at 0.10, 0.30 or 0.50 of the maximal velocity of shortening (V(max)). This procedure was performed before and after a standard conditioning stimulus (CS) that elevated RLC phosphorylation from 0.08 ± 0.01 (rest) to 0.55 ± 0.01 (stimulated) moles phosphate per mol RLC, respectively (n = 9-11) (P shortening speed also increased the activation frequency at which concentric force potentiation was maximal, i.e. from 10 Hz at 0.10 V(max) to 10-25 and 25-45 Hz at 0.30 and 0.50 V(max), respectively. These results indicate that both the magnitude of and activation frequency dependence for concentric force potentiation of mouse EDL muscle is shortening speed dependent. Thus, muscle shortening speed may be a critical factor determining the functional utility of the myosin RLC phosphorylation mechanism.

  1. A Dissociation between Recognition and Hedonic Value in Caloric and Non-caloric Carbonated Soft Drinks

    OpenAIRE

    Franco eDelogu; Claire eHuddas; Katelyn eSteven; Souheila eHachem; Luv eLodhia; Ryan eFernandez; Macee eLogerstedt

    2016-01-01

    Consumption of sugar-sweetened beverages (SSBs) is considered to be a contributor to diabetes and the epidemic of obesity in many countries. The popularity of non-caloric carbonated soft drinks as an alternative to SSBs may be a factor in reducing the health risks associated with SSBs consumption. This study focuses on the perceptual discrimination of SSBs from artificially sweetened beverages (ASBs). Fifty-five college students rated 14 commercially available carbonated soft drinks in terms ...

  2. Conservación por calor

    OpenAIRE

    Cobos García, Angel; Díaz Rubio, Olga

    2011-01-01

    Grao en Nutrición Humana e Dietética Esta unidade didáctica denominada Conservación por calor forma parte da materia «Tecnoloxía do procesado de alimentos» que se impartirá no primeiro semestre do 2º curso do Grao en Nutrición Humana e Dietética. A materia estrutúrase en diferentes unidades didácticas, tratando cada unha delas as diferentes tecnoloxías de procesado dos alimentos, tanto de conservación coma de transformación. A presente unidade didáctica aborda a conservación dos alimentos ...

  3. Caloric vestibular stimulation in aphasic syndrome

    Directory of Open Access Journals (Sweden)

    David eWilkinson

    2013-12-01

    Full Text Available Caloric vestibular stimulation (CVS is commonly used to diagnose brainstem disorder but its therapeutic application is much less established. Based on the finding that CVS increases blood flow to brain structures associated with language and communication, we assessed whether the procedure has potential to relieve symptoms of post-stroke aphasia. Three participants, each presenting with chronic, unilateral lesions to the left hemisphere, were administered daily CVS for 4 consecutive weeks. Relative to their pre-treatment baseline scores, two of the three participants showed significant improvement on both picture and responsive naming at immediate and one-week follow-up. One of these participants also showed improved sentence repetition, and another showed improved auditory word discrimination. No adverse reactions were reported. These data provide the first, albeit tentative, evidence that CVS may relieve expressive and receptive symptoms of aphasia. A larger, sham-controlled study is now needed to further assess efficacy.

  4. Normal Caloric Responses during Acute Phase of Vestibular Neuritis

    Science.gov (United States)

    Lee, Sun-Uk; Park, Seong-Ho; Kim, Hyo-Jung; Koo, Ja-Won

    2016-01-01

    Background and Purpose We report a novel finding of caloric conversion from normal responses into unilateral paresis during the acute phase of vestibular neuritis (VN). Methods We recruited 893 patients with a diagnosis of VN at Dizziness Clinic of Seoul National University Bundang Hospital from 2003 to 2014 after excluding 28 patients with isolated inferior divisional VN (n=14) and those without follow-up tests despite normal caloric responses initially (n=14). We retrospectively analyzed the neurotological findings in four (0.5%) of the patients who showed a conversion from initially normal caloric responses into unilateral paresis during the acute phase. Results In those four patients, the initial caloric tests were performed within 2 days of symptom onset, and conversion into unilateral caloric paresis was documented 1–4 days later. The clinical and laboratory findings during the initial evaluation were consistent with VN in all four patients except for normal findings in bedside head impulse tests in one of them. Conclusions Normal findings in caloric tests should be interpreted with caution during the acute phase of suspected VN. Follow-up evaluation should be considered when the findings of the initial caloric test are normal, but VN remains the most plausible diagnosis. PMID:26932259

  5. Analysis of caloric test responses in sudden hearing loss.

    Science.gov (United States)

    Shih, Cheng-Ping; Chou, Yu-Ching; Chen, Hsin-Chien; Lee, Jih-Chin; Chu, Yueng-Hsiang; Wang, Chih-Hung

    2017-02-01

    Sudden sensorineural hearing loss is characterized by a rapid-onset hearing loss that develops within 3 days. Vertigo may also be present. We conducted a retrospective study to investigate whether the severity of a loss of caloric function is associated with the initial hearing loss and with hearing recovery. Our study population was made up of 135 patients-67 men and 68 women, aged 25 to 71 years (mean: 50.9)-with sudden sensorineural hearing loss who had undergone bithermal caloric testing. We compared various patient factors according to patients' hearing level and their response to caloric testing. We also analyzed the canal paresis (CP) value in patients with an abnormal caloric response according to three factors: disease severity, vertigo, and hearing recovery, and we evaluated the correlation between the loss of caloric function and hearing outcomes. We found that an abnormal caloric response was significantly associated with a profound hearing loss at presentation, the presence of vertigo, and poor hearing recovery. Among patients with an abnormal caloric response, the CP value was significantly correlated with hearing recovery (r = 0.503, p = 0.001). Poor hearing recovery was seen in 80% of patients with a CP value of ≥40% but in only 25% of patients with a value of hearing recovery was worse in the patients with a CP value of ≥40% (p = 0.002). We conclude that a CP value of ≥40% is a significant prognostic factor for an unfavorable treatment outcome.

  6. Characteristics of non caloric dulcorants and their use in children

    Directory of Open Access Journals (Sweden)

    Calzada León Raúl

    2014-07-01

    Full Text Available This is a descriptive review of the elaboration routes, the physical and chemical characteristics, metabolism and clearance, sweetener level, residual flavor, maximal recommended ingestion, security levels and the assessment of growth and development problems in children (from newborns, including prematures, to the end of puberty, of the main no caloric edulcorants used in Mexico. The no caloric edulcorants included in this review are: aspartame, acesulfame-K, sucralose, sacarin, ciclamates, thaumatin, D- tagatose, estevia and alitame.

  7. Shortening amplitude affects the incomplete force recovery after active shortening in mouse soleus muscle.

    Science.gov (United States)

    Van Noten, Pieter; Van Leemputte, Marc

    2009-12-11

    Compared to isometric contraction, the force producing capacity of muscle is reduced (force depression, FD) after a work producing shortening phase. It has been suggested that FD results from an inhibition of cross-bridge binding. Because the rate constants of the exponential force (re)development are thought to be primarily determined by cross-bridge attachment/detachment rate, we aimed to investigate the components of force redevelopment (REDEV) after 0.6, 1.2 and 2.4mm shortening, resulting in varying amounts of FD (from about 5% to about 16%), in mouse soleus muscle (n=11). Compared to isometric force development (DEV), the time to reach steady-state during REDEV was about 3 times longer (370 versus 1261ms) increasing with increasing amplitude. Contrary to a single, a double exponential function with one component set equal to the rate constant of DEV (14.3s(-1)), accurately described REDEV (RMSshortening amplitude and was associated with work delivered during shortening (R(2)=0.75) and FD (R(2)=0.77). We concluded that a work related slow exponential component is induced to the trajectory of incomplete force recovery after shortening, causing FD. These results suggest that after shortening, aside from cross-bridges with normal attachment/detachment rate, cross-bridges with reduced cycling rate are active.

  8. Renal failure induces telomere shortening in the rat heart

    NARCIS (Netherlands)

    Wong, L. S.; Windt, W. A.; Roks, A. J.; van Dokkum, R. P.; Schoemaker, R. G.; de Zeeuw, D.; Henning, R. H.

    2009-01-01

    Background. Renal failure aggravates pathological cardiac remodelling induced by myocardial infarction (MI). Cardiac remodelling is associated with telomere shortening, a marker for biological ageing. We investigated whether mild and severe renal failure shorten cardiac telomeres and excessively sho

  9. [Shortening arthrodesis of three wrist bones].

    Science.gov (United States)

    Delattre, O; Dupont, P; Reau, A F; Rouvillain, J L; Mousselard, H; Catonné, Y

    1997-01-01

    In advanced cases of wrist osteoarthritis with lesions of the radio-scaphoid and mediocarpal joints, and when a proximal row carpectomy is not possible because of lesions of the head of the capitate, we suggest a new technique: The hamate-capitate-lunate shortening arthrodesis with a scaphoid-triquetral resection. The good results observed with proximal row carpectomies, and particularly their long-term reliability, have encouraged us on this new path. Effectively, this operation takes the concept of proximal row carpectomy one step further by reconstructing the head of the capitate with the lunate whose proximal articular surface is often not deteriorated even in very advanced cases of radio and mediocarpal osteoarthritis. The two theoretical concepts of this operation are the shortening of the carpus and respect of the physiological congruence of the radio-lunate joint, the goal being obtain similar results those with proximal row carpectomy, particularly concerning mobility. We present our first two cases with this technique. This new procedure is an alternative to the four bone arthrodesis, particularly in SLAC wrist sequellae when they have evolved to the stage of radio and mediocarpal osteoarthritis.

  10. Changes of ampulla pressure in the semicircular canal of pigeons by caloric stimulation

    Science.gov (United States)

    Wada, Yoshiro; Suzuki, Hiroyuki; Watanabe, Satoru

    Still now several hypotheses about the mechanisms of the caloric nystagmus have been in conclusive. In this study we confirmed the convection effect and the volume change effect of the endolymph in horizontal semicircular canal following the caloric stimulation using pigeons ( Columba livia). Although the direction of the caloric nystagmus depended on the head position and the stimulus site of calorization, the caloric nystagmus disappeared after plugging of horizontal semicircular canal. On the other hand, the ampulla pressure increased by cold calorization and decreased by hot calorization and these pressure changes had no relation to the head position. These results show that the main role of the mechanisms of the caloric nystagmus under 1G is the convection effect but the volume change effect may act on the caloric nystagmus not only under 1G but also under microgravity.

  11. Modeling and design aspects of active caloric regenerators

    Science.gov (United States)

    Engelbrecht, Kurt

    2015-03-01

    A cooling device based on a solid caloric material using, for example, the elastocaloric, magnetocaloric, barocaloric or electrocaloric effect has the potential to replace vapor-compression based systems for a variety of applications. Any caloric device using a solid refrigerant may benefit from using a regenerative cycle to increase the operating temperature span. This presentation shows how all active caloric regenerators can be modeled using similar techniques and how they are related to passive regenerator performance. The advantages and disadvantages of using a regenerative cycle are also discussed. The issue of hysteresis in caloric materials is investigated from a system/thermodynamic standpoint and the effects on cooling power and efficiency are quantified using a numerical model of an active regenerator using model caloric materials with assumed properties. The implementation in a working device will be discussed for elastocaloric and magnetocaloric cooling devices. It is shown that demagnetization effects for magnetocaloric systems and stress concentration effects in elastocaloric system reduce the overall effect in the regenerator and care must be taken in regenerator design for both technologies. Other loss mechanisms outside the regenerator such as heat leaks are also discussed. Finally, experimental results for active magnetic regenerative cooler are given for a range of operating conditions. The most recently published device uses a regenerator consisting of Gd and three alloys of GdY and has demonstrated a COP over 3.

  12. Restricted Airspace

    Data.gov (United States)

    Federal Laboratory Consortium — Redstone Technical Test Center has restricted airspace up to 30,000 feet ASL. Airspace encompasses R-2104 (Redstone). Airspace is used extensively for airborne/UAV...

  13. Safety assessment and caloric value of partially hydrolyzed guar gum.

    Science.gov (United States)

    Finley, John W; Soto-Vaca, Adriana; Heimbach, James; Rao, T P; Juneja, Lekh Raj; Slavin, Joanne; Fahey, George C

    2013-02-27

    Guar gum and partially hydrolyzed guar gum (PHGG) are food ingredients that have been available for many years. PHGG is the partially hydrolyzed product from guar gum obtained from the Indian cluster bean (Cyanopsis tetragonolopus). The gum (CAS Registry No. 9000-30-0) is composed of galactomannan, a gel-forming polysaccharide with a molecular weight ranging from 200 to 300 kDa. The intact and partially hydrolyzed forms have multiple food applications. The intact material can be used to control the viscosity, stability, and texture of foods. PHGG is highly soluble and has little physical impact on foods. Both forms are indigestible but are excellent sources of fermentable dietary fiber. The caloric value of intact guar gum is accepted as 2.0, whereas the caloric value of PHGG has not been firmly established. It is the goal of this paper to review the chemistry, safety, in vivo effects, and caloric value of PHGG.

  14. [A caloric vestibular test with increased positive evidence (author's transl)].

    Science.gov (United States)

    Kurzeja, A; Strauss, P; Kapell, H

    1979-12-01

    A decrease of the variance of a caloric test would increase the importance of the statement of this test. An important source of variance are the differences concerning the timecourse of the induced heat wave, determined by the different anatomic conditions in the petrous bone, particularly the pneumatisation. A constant temperature gradient is obtained by the irigation in a pessimum position with the head flexed 30 degrees to the front. This temperature gradient evokes immediately a constant maximum vestibular stimulus after having reflected the head 90 degrees to the back. Comparing this new method with the traditional irrigation, one can state an important reduction of variance. The dependence of the nystagumus response on caloric irrigation of the petrous bone demands a X-ray-examination according to the technique of Schüller before starting with the caloric examination. In case of differences between the right and left sides the described test would be necessary in our opinion.

  15. Constrained caloric curves and phase transition for hot nuclei

    CERN Document Server

    Borderie, Bernard; Rivet, M F; Raduta, Ad R; Ademard, G; Bonnet, E; Bougault, R; Chbihi, A; Frankland, J D; Galichet, E; Gruyer, D; Guinet, D; Lautesse, P; Neindre, N Le; Lopez, O; Marini, P; Parlog, M; Pawlowski, P; Rosato, E; Roy, R; Vigilante, M

    2013-01-01

    Simulations based on experimental data obtained from multifragmenting quasi-fused nuclei produced in central $^{129}$Xe + $^{nat}$Sn collisions have been used to deduce event by event freeze-out properties in the thermal excitation energy range 4-12 AMeV [Nucl. Phys. A809 (2008) 111]. From these properties and the temperatures deduced from proton transverse momentum fluctuations, constrained caloric curves have been built. At constant average volumes caloric curves exhibit a monotonic behaviour whereas for constrained pressures a backbending is observed. Such results support the existence of a first order phase transition for hot nuclei.

  16. Apuntes de Transmisión del Calor

    OpenAIRE

    2013-01-01

    Esta publicacion está basada en unos apuntes para la parte de Transmisión del Calor de las asignaturas de la ETSAM. Sin embargo, con el tiempo se ha añadido otro material extra que excede ampliamente el contenido del curso.

  17. Cupula dynamics under caloric stimulation of the semicircular canal

    Science.gov (United States)

    Kondrachuk, A. V.; Sirenko, S. P.

    Caloric stimulation of the semicircular canal SC is widely applied in studies of vestibular impairments Barany 1906 suggested that caloric response of SC results from mechanism of endolymph convection due to density changes of endolymph and therefore depends on the action of gravity forces However the Skylab experiments 1983 showed that the caloric reaction of SC can take place even under microgravity The studies of Scherer Clarke 1985 Harada Ariki 1985 Baumgarten et al 1985 considered the thermal expansion of endolymph to be a concurrent mechanism The model of caloric response based on the buoyancy force due to density change in the endolymph induced by thermal stimulation was proposed by Gentine et al 1990 1991 It should be noted that the first qualitative model that took into account the effect of endolymph thermal expansion under local heating to analyze the properties of primary afferents was proposed by Gusev Orlov 1977 However these models failed to answer the question which of the mentioned effects will be dominant under certain conditions The purpose of present study was to account for the expansion and convection of endolymph and to determine under which conditions one mechanism dominates over the other The consideration is based on the following model of SC Kondrachuk Sirenko 1990 an isolated torus filled by a compressible viscous Newton liquid endolymph the torus interior is plugged by an elastic body cupula the cupula surface in contact with endolymph is supposed to be stretched along the

  18. CALOR87: HETC87, MICAP, EGS4, and SPECT

    Energy Technology Data Exchange (ETDEWEB)

    Gabriel, T.A.; Alsmiller, F.S.; Alsmiller, R.G. Jr.; Bishop, B.L.; Hermann, O.W.; Johnson, J.O.

    1987-01-01

    A brief history of CALOR (HETC, EGS, MICAP, SPECT) is presented to indicate the evolution of this code system. Details concerning the current modifications and additions to the high-energy transport code, HETC, are also presented and new comparisons with experimental data are included to verify the new physics improvements. 27 refs., 5 figs.

  19. The caloric vestibular nystagmus during short lasting microgravity

    Science.gov (United States)

    Oosterveld, W. J.; de Jong, H. A. A.; Kortschot, H. W.

    In human subjects the caloric vestibular test was conducted during parabolic flight. The ear irrigation was performed from 35 secs. till 5 secs. before the onset of microgravity. Nystagmography covered a 10-minutes period, including three parabolic manoeuvres of the aircraft. a. The slow phase velocity (SPV) of the caloric nystagmus increased proportionally with the value of the g-force. Introduction of microgravity induced an exponential decrease of the SPV decay. b. The nystagmus disappeared completely in microgravity, but SPV decay showed a specific time constant. c. The averaged time constant values of the caloric nystagmus SPV decay after sudden onset of microgravity and the averaged time constant of the SPV decay following a sudden stop after sustained rotation during 0-g appeared to be on the same level (10.2 s. and 10.6 s.). d. These two averaged time constant values obtained during shortlasting microgravity proved to be on a lower level than those time constants (15.5 secs.; 15.9 secs.) found in ground-based conditions. e. Because of the similarities in the characteristics of both SPV decay's and their accompanying time constants, a common working mechanism of cupular stimulation is likely. Most probably a fluid movement (or pressure) provokes a cupula deflexion followed by a cupula reflexion, either caused by a sudden stop after a sustained rotation or by a sudden onset of microgravity after g-load calorization. The present results support the Bárány convection theory with regard the endolymph stimulatory properties following the caloric test.

  20. Does a detection team shorten duration of untreated psychosis?

    DEFF Research Database (Denmark)

    Nordentoft, Merete; Thorup, Anne; Petersen, Lone;

    2008-01-01

    Duration of untreated psychosis (DUP) is shown to be associated with poor outcome in many domains. It has been shown that it is possible to shorten DUP when combining a detection team and an information campaign. The aim of this study was to evaluate whether DUP was shortened during the first 3 y...

  1. Controlled meal frequency without caloric restriction alters peripheral blood mononuclear cell cytokine production

    Directory of Open Access Journals (Sweden)

    Longo Dan L

    2011-03-01

    Full Text Available Abstract Background Intermittent fasting (IF improves healthy lifespan in animals by a mechanism involving reduced oxidative damage and increased resistance to stress. However, no studies have evaluated the impact of controlled meal frequency on immune responses in human subjects. Objective A study was conducted to establish the effects of controlled diets with different meal frequencies, but similar daily energy intakes, on cytokine production in healthy male and female subjects. Design In a crossover study design with an intervening washout period, healthy normal weight middle-age male and female subjects (n = 15 were maintained for 2 months on controlled on-site one meal per day (OMD or three meals per day (TMD isocaloric diets. Serum samples and peripheral blood mononuclear cells (PBMCs culture supernatants from subjects were analyzed for the presence of inflammatory markers using a multiplex assay. Results There were no significant differences in the inflammatory markers in the serum of subjects on the OMD or TMD diets. There was an increase in the capacity of PBMCs to produce cytokines in subjects during the first month on the OMD or TMD diets. Lower levels of TNF-α, IL-17, MCP-1 and MIP-1β were produced by PBMCs from subjects on the OMD versus TMD diet. Conclusions PBMCs of subjects on controlled diets exhibit hypersensitivities to cellular stimulation suggesting that stress associated with altered eating behavior might affect cytokine production by immune cells upon stimulation. Moreover, stimulated PBMCs derived from healthy individuals on a reduced meal frequency diet respond with a reduced capability to produce cytokines.

  2. Caloric restriction and exercise increase plasma ANGPTL4 levels in humans via elevated free fatty acids

    NARCIS (Netherlands)

    Kersten, S.; Lichtenstein, L.; Steenbergen, E.; Mudde, K.; Hendriks, H.F.J.; Hesselink, M.K.; Schrauwen, P.; Müller, M.

    2009-01-01

    OBJECTIVE-: Plasma lipoprotein levels are determined by the balance between lipoprotein production and clearance. Recently, angiopoietin-like protein 4 (ANGPTL4) was uncovered as a novel endocrine factor that potently raises plasma triglyceride levels by inhibiting triglyceride clearance. However, v

  3. Urinary endogenous sex hormone levels in postmenopausal women after caloric restriction in young adulthood

    NARCIS (Netherlands)

    Elias, SG; Onland-Moret, NC; Peeters, PHM; Rinaldi, S; Kaaks, R; Grobbee, DE; van Noord, PAH

    2004-01-01

    We investigated whether the 1944-1945 Dutch famine has affected postmenopausal sex hormone concentrations with data from 163 women (young adults during the famine). Urinary sex hormone concentrations showed modest elevations with increasing famine exposure. Effects were absent in parous women, but m

  4. Impact of simulated microgravity and caloric restriction on autonomic nervous system function in adipose tissue

    Science.gov (United States)

    Boschmann, Michael; Adams, Frauke; Tank, Jens; Schaller, Karin; Boese, Andrea; Heer, Martina; Klause, Susanne; Luft, Friedrich C.; Jordan, Jens

    2005-08-01

    Long term immobilization and reduced food intake is often associated with development of orthostatic intolerance. Blocking the norepinephrine transporter (NET) can also mimic symptoms of orthostatic intolerance. Therefore, we hypothesized that simulated microgravity (14 days bed rest at head down tilt, BR) can cause changes in postganglionic NET function and adrenoreceptor (AR) sensitivity and these changes can be aggravated by hypocaloric food intake. For testing, two microdialysis probes were inserted into subcutaneous adipose tissue of eight young healthy men at day 1 and 14 of BR and perfused with Ringer's solution and increasing doses of tyramine and isoproterenol in order to simulate NET blockade and stimulate AR, respectively. At day 14 of eucaloric diet and BR, isoproterenol induced lipolysis was greater, whereas at day 14 of hypocaloric diet and BR, tyramine induced lipolysis was greater when compared to day 1. Therefore, the nutritional state affects NET function and AR sensitivity differently during BR.

  5. Lifestyle and nutrition, caloric restriction, mitochondrial health and hormones: Scientific interventions for anti-aging

    Directory of Open Access Journals (Sweden)

    Luis Vitetta

    2008-01-01

    Full Text Available Luis Vitetta1, Bill Anton21Unit of Health Integration, School of Medicine, University of Queensland, Australia; 2Path Lab, Melbourne, AustraliaAbstract: Aging is a universal process to all life forms. The most current and widely accepted definition for aging in humans is that there is a progressive loss of function and energy production that is accompanied by decreasing fertility and increasing mortality with advancing age. The most obvious and commonly recognised consequence of aging and energy decline is a decrease in skeletal muscle function which affects every aspect of human life from the ability to play games, walk and run to chew, swallow and digest food. There is hence a recognised overall decline of an individuals’ fitness for the environment that they occupy. In Westernised countries this decline is gradual and the signs become mostly noticeable after the 5th decade of life and henceforth, where the individual slowly progresses to death over the next three to four decades. Given that the aging process is slow and gradual, it presents with opportunities and options that may ameliorate and improve the overall functional capacity of the organism. Small changes in function may be more amenable and likely to further slow down and possibly reverse some of the deleterious effects of aging, rather, than when the incremental changes are large. This overall effect may then translate into a significant compression of the deleterious aspects of human aging with a resultant increase in human life expectancy.Keywords: human aging, life expectancy, lifespan, energy

  6. Shortening of subjective visual intervals followed by repetitive stimulation.

    Directory of Open Access Journals (Sweden)

    Fuminori Ono

    Full Text Available Our previous research demonstrated that repetitive tone stimulation shortened the perceived duration of the preceding auditory time interval. In this study, we examined whether repetitive visual stimulation influences the perception of preceding visual time intervals. Results showed that a time interval followed by a high-frequency visual flicker was perceived as shorter than that followed by a low-frequency visual flicker. The perceived duration decreased as the frequency of the visual flicker increased. The visual flicker presented in one hemifield shortened the apparent time interval in the other hemifield. A final experiment showed that repetitive tone stimulation also shortened the perceived duration of preceding visual time intervals. We concluded that visual flicker shortened the perceived duration of preceding visual time intervals in the same way as repetitive auditory stimulation shortened the subjective duration of preceding tones.

  7. Uso de transdutores de fluxo de calor no estudo da transferência de calor em alimentos embalados

    Directory of Open Access Journals (Sweden)

    Carciofi B.

    2002-01-01

    Full Text Available A densidade de fluxo de calor que atravessa uma superfície é classicamente determinada mediante a medição das temperaturas apropriadas e da aplicação da Lei de Fourier. Uma alternativa a esse procedimento é a utilização de transdutores de fluxo de calor, os quais geram um sinal elétrico proporcional ao fluxo térmico que os atravessa. Neste trabalho, processos de aquecimento e de resfriamento de alimentos foram estudados em laboratório, utilizando-se um recipiente de vidro cilíndrico para simular uma embalagem. Dois transdutores de fluxo de calor a gradiente tangencial foram previamente instalados no recipiente, revestindo completamente a superfície lateral do mesmo. O recipiente contendo a amostra foi inserido em banho de água circulante à temperatura constante. Os sinais fornecidos pelos transdutores e por termopares inseridos no interior do recipiente foram registrados por um sistema de aquisição de dados computadorizado. Os resultados obtidos com o uso dos transdutores foram comparados com aqueles obtidos através de balanços de energia realizados a partir dos dados experimentais de evolução temporal das temperaturas da amostra junto à superfície interna da embalagem e no centro da mesma. A comparação mostrou que os transdutores de fluxo de calor a gradiente tangencial puderam determinar os fluxos de calor, com tempo de resposta característico dos termopares. Os resultados apresentados mostraram a viabilidade de utilização desses fluxímetros no estudo não destrutivo e não invasivo dos processos de aquecimento e de resfriamento de alimentos, fornecendo informações complementares àquelas obtidas pelo uso de termopares instalados no interior da embalagem.

  8. DESARROLLOS INSTRUMENTALES EN MICROCALORIMETRIA DE CONDUCCIÓN DE CALOR

    Directory of Open Access Journals (Sweden)

    Liliana Giraldo G.

    2010-09-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  9. Caloric values for young sprouts of nine hardwood species

    Energy Technology Data Exchange (ETDEWEB)

    Neenan, M. (An Foras Taluntais, Oak Park, Carlow, Ireland); Steinbeck, K.

    1979-09-01

    Caloric content, specific gravity, and ash content of 6- to 15-year-old sprouts of nine hardwood species were determined in midsummer. Energy values for wood, bark, first order branches, twigs, and leaves were determined with an adiabatic bomb calorimeter. The values found for coppice material averaged 4791 cal/g and were comparable to published values for older wood. Intraspecific differences among tissues were greater than the relatively small but significant differences among species. Differences in yield potential are therefore likely to outweigh variations in caloric content among species where total energy production per unit of land area is concerned. Ash content varied from 0.65 percent for wood to 5.88 percent for bark.

  10. Caloric Effects in Methylammonium Lead Iodide from Molecular Dynamics Simulations

    OpenAIRE

    Liu, Shi; Cohen, Ronald E.

    2016-01-01

    Organic-inorganic hybrid perovskite architecture could serve as a robust platform for materials design to realize functionalities beyond photovoltaic applications. We explore caloric effects in organometal halide perovskites, taking methylammonium lead iodide (MAPbI$_3$) as an example, using all-atom molecular dynamics simulations with a first-principles based interatomic potential. The adiabatic thermal change is estimated directly by introducing different driving fields in the simulations. ...

  11. Age-related decrease in aromatase and estrogen receptor(ERαand ERβ) expression in rat testes: protective effect of low caloric diets

    Institute of Scientific and Technical Information of China (English)

    Khaled Hamden; Dorothee Silandre; Christelle Delalande; Abdefattah El Feki; Serge Carreau

    2008-01-01

    Aim: To examine the effects on rat aging of caloric restriction (CR1) and undernutrition (CR2) on the body and on testicular weights, on two enzymatic antioxidants (superoxide dismutase and catalase), on lipid peroxidation and on the expression of testicular aromatase and estrogen receptors (ER). Methods: CR was initiated in 1-month-old rats and carried on until the age of 18 months. Results: In control and CR2 rats an age-related decrease of the aromatase and of ER (α and β) gene expression was observed; in parallel a diminution of testicular weights, and of the total number and motility of epididymal spermatozo was recorded. In addition, aging in control and CR2 rats was accom-panied by a significant decrease in testicular superoxide dismutase, catalase activities, and an increase in lipid peroxidation level (thiobarbituric acid reactive substance), associated with alterations of spermatogenesis. Conversely, caloric restriction-treatment exerted a protective effect and all the parameters were less affected by aging. Conclusion:These results indicate that during aging, a low caloric diet (not undernutrition) is beneficial for spermatogenesis and likely improves the protection of the cells via an increase of the cellular antioxidant defense system in which aromatase/ER could play a role.

  12. A linear description of shortening induced changes in isometric length-force characteristics of rat muscle

    OpenAIRE

    Meijer, K; Grootenboer, H.J.; Koopman, H.F.J.M.; Huijing, P.A.

    1996-01-01

    Active muscle shortening reduces the isometric force potential of muscle. This observation indicates that the isometric length-force characteristics are altered during muscle shortening. Post-shortening decrease in isometric force depends on starting length, shortening amplitude and shortening velocity. In the present study, post-shortening decrease in isometric force was determined after isokinetic contractions with various shortening amplitudes initiated from different lengths of rat medial...

  13. Calorie restriction increases muscle mitochondrial biogenesis in healthy humans.

    Directory of Open Access Journals (Sweden)

    Anthony E Civitarese

    2007-03-01

    Full Text Available BACKGROUND: Caloric restriction without malnutrition extends life span in a range of organisms including insects and mammals and lowers free radical production by the mitochondria. However, the mechanism responsible for this adaptation are poorly understood. METHODS AND FINDINGS: The current study was undertaken to examine muscle mitochondrial bioenergetics in response to caloric restriction alone or in combination with exercise in 36 young (36.8 +/- 1.0 y, overweight (body mass index, 27.8 +/- 0.7 kg/m(2 individuals randomized into one of three groups for a 6-mo intervention: Control, 100% of energy requirements; CR, 25% caloric restriction; and CREX, caloric restriction with exercise (CREX, 12.5% CR + 12.5% increased energy expenditure (EE. In the controls, 24-h EE was unchanged, but in CR and CREX it was significantly reduced from baseline even after adjustment for the loss of metabolic mass (CR, -135 +/- 42 kcal/d, p = 0.002 and CREX, -117 +/- 52 kcal/d, p = 0.008. Participants in the CR and CREX groups had increased expression of genes encoding proteins involved in mitochondrial function such as PPARGC1A, TFAM, eNOS, SIRT1, and PARL (all, p < 0.05. In parallel, mitochondrial DNA content increased by 35% +/- 5% in the CR group (p = 0.005 and 21% +/- 4% in the CREX group (p < 0.004, with no change in the control group (2% +/- 2%. However, the activity of key mitochondrial enzymes of the TCA (tricarboxylic acid cycle (citrate synthase, beta-oxidation (beta-hydroxyacyl-CoA dehydrogenase, and electron transport chain (cytochrome C oxidase II was unchanged. DNA damage was reduced from baseline in the CR (-0.56 +/- 0.11 arbitrary units, p = 0.003 and CREX (-0.45 +/- 0.12 arbitrary units, p = 0.011, but not in the controls. In primary cultures of human myotubes, a nitric oxide donor (mimicking eNOS signaling induced mitochondrial biogenesis but failed to induce SIRT1 protein expression, suggesting that additional factors may regulate SIRT1 content

  14. Phenomenological models of the dynamics of muscle during isotonic shortening.

    Science.gov (United States)

    Yeo, Sang Hoon; Monroy, Jenna A; Lappin, A Kristopher; Nishikawa, Kiisa C; Pai, Dinesh K

    2013-09-27

    We investigated the effectiveness of simple, Hill-type, phenomenological models of the force-length-velocity relationship for simulating measured length trajectories during muscle shortening, and, if so, what forms of the model are most useful. Using isotonic shortening data from mouse soleus and toad depressor mandibulae muscles, we showed that Hill-type models can indeed simulate the shortening trajectories with sufficiently good accuracy. However, we found that the standard form of the Hill-type muscle model, called the force-scaling model, is not a satisfactory choice. Instead, the results support the use of less frequently used models, the f-max scaling model and force-scaling with parallel spring, to simulate the shortening dynamics of muscle.

  15. Augmentation of deglutitive thyrohyoid muscle shortening by the Shaker Exercise.

    Science.gov (United States)

    Mepani, Rachel; Antonik, Stephen; Massey, Benson; Kern, Mark; Logemann, Jerilyn; Pauloski, Barbara; Rademaker, Alfred; Easterling, Caryn; Shaker, Reza

    2009-03-01

    Earlier studies of the effect of 6 weeks of the Shaker Exercise have shown significant increase in UES opening and anterior excursion of larynx and hyoid during swallowing in patients with upper esophageal sphincter (UES) dysfunction, resulting in elimination of aspiration and resumption of oral intake. This effect is attributed to strengthening of the suprahyoid muscles, as evidenced by comparison of electromyographic changes in muscle fatigue before and after completion of the exercise regime. The effect of this exercise on thyrohyoid muscle shortening is unknown. Therefore the aim of this study was to determine the effect of the exercise on thyrohyoid muscle shortening. We studied 11 dysphagic patients with UES dysfunction. Six were randomized to traditional swallowing therapy and five to the Shaker Exercise. Videofluoroscopy was used to measure deglutitive thyrohyoid shortening before and after completion of assigned therapy regimen. Maximum thyrohyoid muscle shortening occurred at close temporal proximity to the time of maximal thyroid cartilage excursion. The percent change in thyrohyoid distance from initiation of deglutition to maximal anterior/superior hyoid excursion showed no statistically significant difference between the two groups prior to either therapy (p = 0.54). In contrast, after completion of therapy, the percent change in thyrohyoid distance in the Shaker Exercise group was significantly greater compared to the traditional therapy (p = 0.034). The Shaker Exercise augments the thyrohyoid muscle shortening in addition to strengthening the suprahyoid muscles. The combination of increased thyrohyoid shortening and suprahyoid strengthening contributes to the Shaker Exercise outcome of deglutitive UES opening augmentation.

  16. Biochemical response to chronic shortening in unloaded soleus muscles

    Science.gov (United States)

    Jaspers, S. R.; Fagan, J. M.; Tischler, M. E.

    1985-01-01

    One leg of tail-casted suspended rats was immobilized in a plantar-flexed position to test whether chronic shortening of posterior leg muscles affected the metabolic response to unloading. The immobilized plantaris and gastrocnemius muscles of these animals showed approximately 20 percent loss of muscle mass in contrast to simply a slower growth rate with unloading. Loss of mass of the soleus muscle during suspension was not accentuated by chronic shortening. Although protein degradation in the isolated soleus muscle of the plantar-flexed limb was slightly faster than in the contralateral free limb, this difference was offset by faster synthesis of the myofibrillar protein fraction of the chronically shortened muscle. Total adenine nucleotides were 17 percent lower (P less than 0.005) in the chronically shortened soleus muscle following incubation. Glutamate, glutamine, and alanine metabolism showed little response to chronic shortening. These results suggest that, in the soleus muscle, chronic shortening did not alter significantly the metabolic responses to unloading and reduced activity.

  17. Consequences of crown shortening canine teeth in Greenland sled dogs

    DEFF Research Database (Denmark)

    Kortegaard, H E; Anthony Knudsen, T; Dahl, S

    2015-01-01

    OBJECTIVES: To evaluate the consequences of crown shortening, focusing on the prevalence of pulp exposure and periapical pathology in Greenland sled dogs that had had their canine crowns shortened at an early age. METHODS: Five cadaver heads and 54 sled dogs underwent an oral examination for dental...... fractures and pulp exposure of canines. All canines were radiographed and evaluated for periapical pathology. RESULTS: The prevalence of canine pulp exposure in 12 (5 heads and 7 dogs) crown shortened dogs was 91 · 7%, and 21 · 3% in 47 not-crown shortened dogs. A significant (P ... exposure of the canines in the crown shortened group compared to the not-crown shortened group was seen with a relative risk of 4 · 3 on a dog basis and a relative risk of 12 · 2 on a tooth basis. In dogs with pulp exposure of canines (n = 51) the prevalence of periapical pathology was 82 · 4%, but only 0...

  18. Effect of shortened sleep on energy expenditure, core body temperature, and appetite: a human randomised crossover trial

    OpenAIRE

    Masanobu Hibi; Chie Kubota; Tomohito Mizuno; Sayaka Aritake; Yuki Mitsui; Mitsuhiro Katashima; Sunao Uchida

    2017-01-01

    The effects of sleep restriction on energy metabolism and appetite remain controversial. We examined the effects of shortened sleep duration on energy metabolism, core body temperature (CBT), and appetite profiles. Nine healthy men were evaluated in a randomised crossover study under two conditions: a 3.5-h sleep duration and a 7-h sleep duration for three consecutive nights followed by one 7-h recovery sleep night. The subjects’ energy expenditure (EE), substrate utilisation, and CBT were co...

  19. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    CERN Document Server

    Alajajian, S E; Reagan, A J; Alajajian, S C; Frank, M R; Mitchell, L; Lahne, J; Danforth, C M; Dodds, P S

    2015-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the "caloric content" of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of "caloric input", "caloric output", and the ratio of these measures---"caloric balance"---are all strong correlates with health and well-being demographics for the contiguous United States. Our caloric balance measure outperforms both its constituent quantities, is tunable to specific demographic measures such as diabetes rates, provides a real-time signal reflecting a population's health, and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can m...

  20. A linear description of shortening induced changes in isometric length-force characteristics of rat muscle

    NARCIS (Netherlands)

    Meijer, K.; Grootenboer, H.J.; Koopman, H.F.J.M.; Huijing, P.A.

    1996-01-01

    Active muscle shortening reduces the isometric force potential of muscle. This observation indicates that the isometric length-force characteristics are altered during muscle shortening. Post-shortening decrease in isometric force depends on starting length, shortening amplitude and shortening veloc

  1. The mechanics of mouse skeletal muscle when shortening during relaxation.

    Science.gov (United States)

    Barclay, C J; Lichtwark, G A

    2007-01-01

    The dynamic properties of relaxing skeletal muscle have not been well characterised but are important for understanding muscle function during terrestrial locomotion, during which a considerable fraction of muscle work output can be produced during relaxation. The purpose of this study was to characterise the force-velocity properties of mouse skeletal muscle during relaxation. Experiments were performed in vitro (21 degrees C) using bundles of fibres from mouse soleus and EDL muscles. Isovelocity shortening was applied to muscles during relaxation following short tetanic contractions. Using data from different contractions with different shortening velocities, curves relating force output to shortening velocity were constructed at intervals during relaxation. The velocity component included contributions from shortening of both series elastic component (SEC) and contractile component (CC) because force output was not constant. Early in relaxation force-velocity relationships were linear but became progressively more curved as relaxation progressed. Force-velocity curves late in relaxation had the same curvature as those for the CC in fully activated muscles but V(max) was reduced to approximately 50% of the value in fully activated muscles. These results were the same for slow- and fast-twitch muscles and for relaxation following maximal tetani and brief, sub-maximal tetani. The measured series elastic compliance was used to partition shortening velocity between SEC and CC. The curvature of the CC force-velocity relationship was constant during relaxation. The SEC accounted for most of the shortening and work output during relaxation and its power output during relaxation exceeded the maximum CC power output. It is proposed that unloading the CC, without any change in its overall length, accelerated cross-bridge detachment when shortening was applied during relaxation.

  2. Frying performance of palm-based solid frying shortening.

    Science.gov (United States)

    Omar, M N; Nor-Nazuha, M N; Nor-Dalilah, M N; Sahri, M M

    2010-03-15

    In order to evaluate the frying performance of palm-based solid frying shortening against standard olein, the fresh potato chips were fried in both frying media using an open fryer. After frying the chips for 40 h in an open batch fryer, it was found that the frying quality of palm-based solid frying shortening was better than standard palm olein in terms of Free Fatty Acid (FFA) values, Total Polar Content (TPC) and Total Polymeric Material (TPM). Solid shortening gave FFA, TPC and TPM values of 0.7, 15.3 and 2.67%, respectively, whilst standard palm olein gave values for FFA, TPC and TPM of 1.2, 19.6 and 3.10%, respectively. In terms of sensory mean scores, sensory panelists preferred the color of potato chips fried in solid shortening on the first day of frying, while on the third and fifth day of frying there were no significant differences (p palm olein when used for deep fat frying in terms of FFA values, total polar content and total polymeric material, especially for starch-based products such as potato chips. The result also shows that, in terms of sensory mean scores, after frying for 40 h, the sensory panelists gave higher scores in terms of taste, flavor and crispiness for potato chips fried in palm-based solid shortening.

  3. La isla de calor estival en Temuco, Chile

    Directory of Open Access Journals (Sweden)

    Alicia Capelli de Steffens

    2001-01-01

    Full Text Available Temuco es una ciudad localizada en el centro sur de Chile (38º 45’ S y 72º 40’ W. Morfológicamente, el sitio de la ciudad corresponde a las terrazas fluviales del río Cautín que se desarrollan en forma encajonada entre los cerros Ñielol (350 m y Conunhueno (360 m. Esta ciudad se ha desarrollado rápidamente en las últimas décadas, por lo tanto es necesario conocer el efecto antrópico en la misma. Para evaluar parte de ese efecto se analiza la isla de calor urbana estival en la ciudad de Temuco, Chile. Se efectuaron mediciones de temperatura del aire y humedad a través de la ciudad para determinar la forma y la intensidad de la isla de calor urbano. Se utilizaron estaciones móviles e información de una estación meteorológica fija. La ciudad presenta un comportamiento térmico diferente a lo largo del día. Durante el día genera una isla de calor que responde en líneas generales al modelo ideal de calentamiento urbano. La intensidad de la isla calórica (∆Tu-r fue 6.3ºC y 1.2ºC durante el día y la noche, respectivamente. La influencia de los cerros que limitan la ciudad es importante. El estudio confirma la idea que el clima urbano de una ciudad es un mosaico de microclimas que interactuan continuamente.

  4. A crise do socialismo analisada no calor da hora

    Directory of Open Access Journals (Sweden)

    Reginaldo Benedito Dias

    2009-11-01

    Full Text Available O presente artigo demonstra como os acontecimentos que levaram à crise e desintegração dos países do bloco soviético foram analisados no calor dos acontecimentos, tomando como parâmetro os livros "Nós, o povo" e "A desintegração do monolito", selecionados por causa das diferentes perspectivas metodológicas e ideológicas que representam.  

  5. Shortening induced effects on force (re)development in pig urinary smooth muscle

    OpenAIRE

    van Asselt, Els; Pel, Johan; van Mastrigt, Ron

    2007-01-01

    textabstractIntroduction: When muscle is allowed to shorten during an active contraction, the maximum force that redevelops after shortening is smaller than the isometric force at the same muscle length without prior shortening. We studied the course of force redevelopment after shortening in smooth muscle to unravel the mechanism responsible for this deactivation. Method: In a first series of measurements the shortening velocity was varied resulting in different shortening amplitudes. In a s...

  6. Trans Fatty Acid content in Danish margarines and shortenings

    DEFF Research Database (Denmark)

    Leth, Torben; Bysted, Anette; Hansen, Kirsten

    2003-01-01

    in shortenings, averaging about 6-7%. Long-chain TFA from hydrogenated,fish oil, although present in 13 brands in 1995, were not found at all in the 1999 samples. Trans-linoleic acids or CLA were not found. The reduction in TFA content in margarines has not resulted in a systematic change over the years......Margarines and shortenings have been major contributors to the intake by humans of the probably atherogenic trans FA (TFA). In 1999, all 73 brands of margarines and shortenings on the Danish market were analyzed by GLC on a 50-m highly polar capillary column, and the results were compared...... in the content of saturated FA, monounsaturated FA, or PUFA. Calculated from sales figures, the intake of TFA decreased from 2.2 g per capita per year in 1992, to 1.5 g in 1995, and to 0.4 g in, 1999....

  7. Isla de calor en Toluca, México

    Directory of Open Access Journals (Sweden)

    Carlos Constantino Morales Méndez

    2007-01-01

    Full Text Available El clima de la ciudad de Toluca y del mundo ha sido modificado como consecuencia del crecimiento de su población y el aumento de las dimensiones de su distribución territorial. Las variaciones atmosféricas son más acusadas entre los espacios urbanos y rurales a medida que las ciudades son más grandes y su mancha urbana es más extensa,así como de la reducción de la vegetación, el aumento en la calefacción en casas y edificios y por la contaminación del aire. Para identificar los espacios con calor más intenso por la infraestructura urbana, se propone una metodología que consiste en la determinación de los valores de temperatura que se registraron en dos días típicos de invierno y verano, durante el día y la noche,mostrando la distribución de la isla de calor en la zona de estudio, a partir de los datos delas estaciones de la Red Automática de Monitoreo Ambiental (RAMA. Asimismo, se considera el comportamiento y variación de algunas variables atmosféricas como humedad relativa, precipitación y viento, para mostrar su comportamiento relativamente anómalo en la zona urbana.

  8. High monetary reward rates and caloric rewards decrease temporal persistence

    Science.gov (United States)

    Bode, Stefan; Murawski, Carsten

    2017-01-01

    Temporal persistence refers to an individual's capacity to wait for future rewards, while forgoing possible alternatives. This requires a trade-off between the potential value of delayed rewards and opportunity costs, and is relevant to many real-world decisions, such as dieting. Theoretical models have previously suggested that high monetary reward rates, or positive energy balance, may result in decreased temporal persistence. In our study, 50 fasted participants engaged in a temporal persistence task, incentivised with monetary rewards. In alternating blocks of this task, rewards were delivered at delays drawn randomly from distributions with either a lower or higher maximum reward rate. During some blocks participants received either a caloric drink or water. We used survival analysis to estimate participants' probability of quitting conditional on the delay distribution and the consumed liquid. Participants had a higher probability of quitting in blocks with the higher reward rate. Furthermore, participants who consumed the caloric drink had a higher probability of quitting than those who consumed water. Our results support the predictions from the theoretical models, and importantly, suggest that both higher monetary reward rates and physiologically relevant rewards can decrease temporal persistence, which is a crucial determinant for survival in many species. PMID:28228517

  9. Challenges in Shortening New Product Introduction in the Pharmaceutical Industry

    DEFF Research Database (Denmark)

    Hansen, Klaus Reinholdt Nyhuus; Grunow, Martin

    2010-01-01

    Drug developing companies are forced to utilize the effective protection of the patent by focusing on shortening the new product introduction [NPI] process measured as Time-to-Market [TTM]. Here the NPI process is considered and the trade-offs, which have to be address in the future are identified...

  10. Cellular Consequences of Telomere Shortening in Histologically Normal Breast Tissues

    Science.gov (United States)

    2013-09-01

    in Figure 1, telomere shortening occurs specifically in luminal epithelial cells, but not in myoepithelial cells, in histologically normal terminal...the adjacent myoepithelial cells (panel A). In contrast, some TDLUs demonstrate dim telomere signals in the luminal cells when compared to the...adjacent myoepithelial cells (panel B). Through digital image analysis, quantitative determination of the telomere FISH signals confirms this moderated

  11. A technique for nailing severely shortened and displaced tibia fractures.

    Science.gov (United States)

    Krause, Peter C; Whatley, Adam N; Mautner, James F

    2008-02-01

    Previously described techniques using external fixators or large distractors can simplify the closed nailing of tibia fractures and nonunions. However, delayed intramedullary nailing can be especially challenging when significant shortening or translation has occurred. We present a modification of an old technique for external fixator-assisted closed tibial nailing in these difficult cases.

  12. Residual force enhancement following shortening is speed-dependent

    Science.gov (United States)

    Fortuna, Rafael; Power, Geoffrey A.; Mende, Esther; Seiberl, Wolfgang; Herzog, Walter

    2016-01-01

    The steady-state isometric force following active muscle shortening or lengthening is smaller (force depression; FD) or greater (residual force enhancement; RFE) than a purely isometric contraction at the corresponding length. The mechanisms underlying these phenomena are not explained within the context of the cross-bridge theory and are rarely studied in concert. Previous studies have shown RFE to be speed-independent. In the present study, we investigated if RFE preceded by active shortening is time-dependent by electrically evoking RFE in the human adductor pollicis muscle. The results shown that a slow stretch following FD fully re-established RFE compared to higher speeds of stretch. The mechanism(s) responsible for the recovery of RFE following a preceding shortening contraction (FD) might be associated with the recovery of cross-bridge based force and/or the re-engagement of a passive structural element (titin). Voluntary interaction with one’s environment involves highly coordinated shortening and lengthening muscle contractions. Therefore comprehending these history-dependent muscle properties in the context of movement control is paramount in understanding the behavior of in vivo motor control. PMID:26869508

  13. Telomere shortening reduces Alzheimer's disease amyloid pathology in mice

    NARCIS (Netherlands)

    Rolyan, Harshvardhan; Scheffold, Annika; Heinrich, Annette; Begus-Nahrmann, Yvonne; Langkopf, Britta Heike; Hoelter, Sabine M.; Vogt-Weisenhorn, Daniela M.; Liss, Birgit; Wurst, Wolfgang; Lie, Dieter Chichung; Thal, Dietmar Rudolf; Biber, Knut; Rudolph, Karl Lenhard

    2011-01-01

    Alzheimer's disease is a neurodegenerative disorder of the elderly and advancing age is the major risk factor for Alzheimer's disease development. Telomere shortening represents one of the molecular causes of ageing that limits the proliferative capacity of cells, including neural stem cells. Studie

  14. Sleep Restriction Worsens Mood and Emotion Regulation in Adolescents

    Science.gov (United States)

    Baum, Katherine T.; Desai, Anjali; Field, Julie; Miller, Lauren E.; Rausch, Joseph; Beebe, Dean W.

    2014-01-01

    Background: The relationship between inadequate sleep and mood has been well-established in adults and is supported primarily by correlational data in younger populations. Given that adolescents often experience shortened sleep on school nights, we sought to better understand the effect of experimentally induced chronic sleep restriction on…

  15. Moderate stem-cell telomere shortening rate postpones cancer onset in a stochastic model

    Science.gov (United States)

    Holbek, Simon; Bendtsen, Kristian Moss; Juul, Jeppe

    2013-10-01

    Mammalian cells are restricted from proliferating indefinitely. Telomeres at the end of each chromosome are shortened at cell division and when they reach a critical length, the cell will enter permanent cell cycle arrest—a state known as senescence. This mechanism is thought to be tumor suppressing, as it helps prevent precancerous cells from dividing uncontrollably. Stem cells express the enzyme telomerase, which elongates the telomeres, thereby postponing senescence. However, unlike germ cells and most types of cancer cells, stem cells only express telomerase at levels insufficient to fully maintain the length of their telomeres, leading to a slow decline in proliferation potential. It is not yet fully understood how this decline influences the risk of cancer and the longevity of the organism. We here develop a stochastic model to explore the role of telomere dynamics in relation to both senescence and cancer. The model describes the accumulation of cancerous mutations in a multicellular organism and creates a coherent theoretical framework for interpreting the results of several recent experiments on telomerase regulation. We demonstrate that the longest average cancer-free lifespan before cancer onset is obtained when stem cells start with relatively long telomeres that are shortened at a steady rate at cell division. Furthermore, the risk of cancer early in life can be reduced by having a short initial telomere length. Finally, our model suggests that evolution will favor a shorter than optimal average cancer-free lifespan in order to postpone cancer onset until late in life.

  16. Shortening induced effects on force (re)development in pig urinary smooth muscle

    NARCIS (Netherlands)

    E. van Asselt (Els); J.J.M. Pel (Johan); R. van Mastrigt (Ron)

    2007-01-01

    textabstractIntroduction: When muscle is allowed to shorten during an active contraction, the maximum force that redevelops after shortening is smaller than the isometric force at the same muscle length without prior shortening. We studied the course of force redevelopment after shortening in smooth

  17. Low Caloric Sweeteners for Diabetes and Obesity Care and Their

    Directory of Open Access Journals (Sweden)

    Mohammad Asif

    2015-10-01

    Full Text Available Diabetes and obesity are two common human disorders that affecting human health and invite various diseases and disorders in normal body functions. These diseases are very common worldwide. Diabetes occurs when high blood sugar levels develop. This happens when body can’t make and use all of the insulin it needs to blood sugar normally to keep blood sugar levels as normal as possible to control diabetes. Diabetic patients will need to follow a diet plan, do exercise and possibly take insulin injections. As part of eating plan, health care provider, and dietitian may ask to limit the amount of carbohydrates eat each day. Low-calorie sweeteners are one easy tool to help for follow eating plan. Obesity is more susceptible and often been associated with frequent ingestion of high energy food in high amount and high intake of sugars such as fermentable sugars such as sucrose, fructose, glucose, and maltose. Both diseases are may be genetically or due to hormonal imbalances. High energy sweeteners may causes caries in the teeth particularly susceptible to the children. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in obesity. Fortunately, low calorie artificial and natural alternatives of sugars have been developed as alternatives to fermentable sugars and have shown promise in these health issues. Although there are only few artificial sweeteners (saccharin, aspartame, acesulfam potassium, sucralose, cyclamate that have been approved as food additives by the Food and Drug Administration and additional other low-caloric sweeteners (sugar alcohols, neotame, stevia, erythritol, xylitol, tagatose that have FDA-generally recognized as safe. Given the health impact of sugars and other carbohydrates, professionals should be aware of the marketed available low caloric sweeteners and both their benefits and potential risks.

  18. Methods for Shortening and Extending the Carbon Chain in Carbohydrates

    DEFF Research Database (Denmark)

    Monrad, Rune Nygaard

    2008-01-01

    Carbohydrates play a central role in a variety of physiological and pathological processes such as HIV, cancer and diabetes. The understanding of these processes and the development of specific therapeutic agents is relying on the ability to chemically synthesize unnatural sugars, glycoconjugates...... and carbohydrate mimetics. Such polyhydroxylated compounds are conveniently synthesized from carbohydrates, however, due to the scarcity of many sugars from nature, efficient methods for transformation of readily available carbohydrates into valuable chiral building blocks are required. The work presented...... in this thesis focuses on the development and application of transition metal mediated methods for shortening and extending the carbon chain in carbohydrates thereby providing access to lower and higher sugars.A new catalytic procedure for shortening unprotected sugars by one carbon atom has been developed...

  19. Estimation of circumferential fiber shortening velocity by echocardiography.

    Science.gov (United States)

    Ruschhaupt, D G; Sodt, P C; Hutcheon, N A; Arcilla, R A

    1983-07-01

    The M-mode and two-dimensional echocardiograms of 40 young patients were analyzed to compare the mean circumferential fiber shortening velocity (Vcf) of the left ventricle calculated separately by two methods. The mean circumferential fiber shortening velocity was derived from the M-mode echocardiogram as minor axis shortening/ejection time and derived from the two-dimensional echocardiogram as actual circumference change/ejection time. With computer assistance, circumference was determined from the short-axis two-dimensional echocardiographic images during end-diastole and end-systole. Good correlations were obtained between the left ventricular diameter derived by M-mode echocardiography and the vertical axis during end-diastole (r = 0.79) and end-systole (r = 0.88) derived by two-dimensional echocardiography. Likewise, high correlations were noted between diameter and circumference in end-diastole (r = 0.89) and end-systole (r = 0.88). However, comparison of Vcf obtained by M-mode echocardiography with that obtained by two-dimensional echocardiography showed only fair correlation (r = 0.68). Moreover, the diameter/circumference ratio determined in end-diastole and end-systole differed significantly (p less than 0.001), possibly owing to the change in geometry of the ventricular sector image during systole. Although Vcf derived by M-mode echocardiography is a useful index of left ventricular performance, it does not truly reflect the circumference change during systole.

  20. Meat toughening does not occur when rigor shortening is prevented.

    Science.gov (United States)

    Koohmaraie, M; Doumit, M E; Wheeler, T L

    1996-12-01

    The objective of this experiment was to test the hypothesis that meat toughening during the first 24 h postmortem results from sarcomere shortening during rigor mortis development. Eleven market-weight lambs were used to measure changes in shear force of clamped longissimus during rigor development. Within 15 min of exsanguination, while attached at both ends, each longissimus was separated from the vertebrae body and clamped between three sets of metal plates to prevent muscle shortening (six clamped sections per lamb). Five of the clamped sections were placed at -1.1 degrees C for 0, 3, 6, 12, or 24 h. After storage at their respective times at -1.1 degrees C, the samples were placed at -30 degrees C for 90 min and then at -5 degrees C for 8 d. The sixth section (168-h section) was stored at -1.1 degrees C for the first 24 h, at 4 degrees C for 144 h, and then treated the same as other sampling times. Sections were sampled for pH, sarcomere length, shear force, and Western blot analyses before and after storage at -5 degrees C. Shear force values were the same (P > .05) from 0 to 24 h (4.5 kg at 0 h to 4.9 kg at 24 h) then declined (P slaughter is most likely due to sarcomere shortening.

  1. The effect of shortening history on isometric and dynamic muscle function.

    Science.gov (United States)

    McDaniel, John; Elmer, Steven J; Martin, James C

    2010-03-03

    Despite numerous reports on isometric force depression, few reports have quantified force depression during active muscle shortening (dynamic force depression). The purpose of this investigation was to determine the influence of shortening history on isometric force following active shortening, force during isokinetic shortening, and velocity during isotonic shortening. The soleus muscles of four cats were subjected to a series of isokinetic contractions at three shortening velocities and isotonic contractions under three loads. Muscle excursions initiated from three different muscle lengths but terminated at a constant length. Isometric force produced subsequent to active shortening, and force or shortening velocity produced at a specific muscle length during shortening, were compared across all three conditions. Results indicated that shortening history altered isometric force by up to 5%, force during isokinetic shortening up to 30% and shortening velocity during isotonic contractions by up to 63%. Furthermore, there was a load by excursion interaction during isotonic contractions such that excursion had the most influence on shortening velocity when the loads were the greatest. There was not a velocity by excursion interaction during isokinetic contractions. Isokinetic and isotonic power-velocity relationships displayed a downward shift in power as excursions increased. Thus, to discuss force depression based on differences in isometric force subsequent to active shortening may underestimate its importance during dynamic contractions. The presence of dynamic force depression should be realized in sport performance, motor control modeling and when controlling paralyzed limbs through artificial stimulation.

  2. Use of caloric and noncaloric sweeteners in US consumer packaged foods, 2005-2009.

    Science.gov (United States)

    Ng, Shu Wen; Slining, Meghan M; Popkin, Barry M

    2012-11-01

    Our understanding of the use of caloric and noncaloric sweeteners in the US food supply is limited. This study uses full ingredient list and Nutrition Facts label data from Gladson Nutrition Database and nationally representative purchases of consumer packaged foods from Nielsen Homescan in 2005 through 2009 to understand the use of caloric sweeteners (including fruit juice concentrate) and noncaloric sweeteners in consumer packaged foods. Of the 85,451 uniquely formulated foods purchased during 2005 through 2009, 75% contain sweeteners (68% with caloric sweetener only, 1% with noncaloric sweetener only, 6% with both caloric and noncaloric sweeteners). Caloric sweetener are in >95% of cakes/cookies/pies, granola/protein/energy bars, ready-to-eat cereals, sweet snacks, and sugar-sweetened beverages. Noncaloric sweetener are in >33% of yogurts and sport/energy drinks, 42% of waters (plain or flavored), and most dietetic sweetened beverages. Across unique products, corn syrup is the most commonly listed sweetener, followed by sorghum, cane sugar, high-fructose corn syrup, and fruit juice concentrate. Also, 77% of all calories purchased in the United States in 2005-2009 contained caloric sweeteners and 3% contained noncaloric sweeteners, and 73% of the volume of foods purchased contained caloric sweetener and 15% contained noncaloric sweetener. Trends during this period suggest a shift toward the purchase of noncaloric sweetener-containing products. Our study poses a challenge toward monitoring sweetener consumption in the United States by discussing the need and options available to improve measures of caloric sweetener and noncaloric sweetener and additional requirements on Nutrition Facts labels on consumer packaged foods.

  3. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    OpenAIRE

    Luiz Oswaldo Carneiro Rodrigues; Flávio de Castro Magalhães

    2004-01-01

    O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de ...

  4. Structural limits on force production and shortening of smooth muscle.

    Science.gov (United States)

    Siegman, Marion J; Davidheiser, Sandra; Mooers, Susan U; Butler, Thomas M

    2013-02-01

    This study determined the factors that limit force production and shortening in two smooth muscles having very different relationships between active and passive force as a function of muscle length. The rat anococcygeus muscle develops active force over the range of lengths 0.2-2.0× the optimum length for force production (Lo). Passive tension due to extension of the resting muscle occurs only at lengths exceeding Lo. In contrast, the rabbit taenia coli develops force in the range of lengths 0.4-1.1 Lo, and passive force which is detectable at 0.56 Lo, increases to ~0.45 maximum active force at Lo, and increases sharply with further extension. The anococcygeus muscle can shorten to 0.2 Lo and the taenia coli to 0.4 Lo. Dynamic stiffness and energy usage at short muscle lengths suggest that the limit of shortening in the taenia coli, in contrast to the anococcygeus muscle, is not due to a failure of cross bridge interaction. Phosphorylation of the regulatory myosin light chains in intact muscles decreased to a small extent at short lengths compared to the decrease in force production. The differences in force production and the extent of shortening in the two muscles was maintained even when, following permeabilization, the myosin light chains were irreversibly phosphorylated with ATPγS, indicating that differences in activation played little, if any role. Ultrastructural studies on resting and activated muscles show that the taenia coli, which is rich in connective tissue (unlike the anococcygeus muscle) undergoes marked cellular twisting and contractile filament misalignment at short lengths with compression of the extracellular matrix. As a result, force is not transmitted in the longitudinal axis of the muscle, but is dissipated against an internal load provided by the compressed extracellular matrix. These observations on two very different normal smooth muscles reveal how differences in the relative contribution of active and passive structural elements

  5. Shortening Tuberculosis Treatment With Fluoroquinolones: Lost in Translation?

    Science.gov (United States)

    Lanoix, Jean-Philippe; Chaisson, Richard E; Nuermberger, Eric L

    2016-02-15

    The disappointing recent failure of fluoroquinolone-containing regimens to shorten the duration of tuberculosis treatment in costly phase 3 trials has raised serious questions about the reliability of preclinical tuberculosis models, especially mice, and the current paradigm of regimen development. Therefore we re-examined data from murine models and early-stage clinical trials on which the pivotal trials were based, concluding that phase 3 trial results were in line with preceding studies. Finally, we offer suggestions for a more efficient and integrated preclinical and clinical regimen development program where quantitative pharmacokinetic and pharmacodynamic models more predictive of curative treatment durations are set forth.

  6. Influence on longevity of blueberry, cinnamon, green and black tea, pomegranate, sesame, curcumin, morin, pycnogenol, quercetin, and taxifolin fed iso-calorically to long-lived, F1 hybrid mice.

    Science.gov (United States)

    Spindler, Stephen R; Mote, Patricia L; Flegal, James M; Teter, Bruce

    2013-04-01

    Phytonutrients reportedly extend the life span of Caenorhabditis elegans, Drosophila, and mice. We tested extracts of blueberry, pomegranate, green and black tea, cinnamon, sesame, and French maritime pine bark (Pycnogenol and taxifolin), as well as curcumin, morin, and quercetin for their effects on the life span of mice. While many of these phytonutrients reportedly extend the life span of model organisms, we found no significant effect on the life span of male F1 hybrid mice, even though the dosages used reportedly produce defined therapeutic end points in mice. The compounds were fed beginning at 12 months of age. The control and treatment groups were iso-caloric with respect to one another. A 40% calorically restricted and other groups not reported here did experience life span extension. Body weights were un-changed relative to controls for all but two supplemented groups, indicating most supplements did not change energy absorption or utilization. Tea extracts with morin decreased weight, whereas quercetin, taxifolin, and Pycnogenol together increased weight. These changes may be due to altered locomotion or fatty acid biosynthesis. Published reports of murine life span extension using curcumin or tea components may have resulted from induced caloric restriction. Together, our results do not support the idea that isolated phytonutrient anti-oxidants and anti-inflammatories are potential longevity therapeutics, even though consumption of whole fruits and vegetables is associated with enhanced health span and life span.

  7. Herdabilidade da necessidade de calor para a antese e brotação em pessegueiro

    Directory of Open Access Journals (Sweden)

    Citadin Idemir

    2003-01-01

    Full Text Available A herdabilidade da necessidade de calor para antese e brotação em pessegueiro [Prunus persica (L. Batsch] foi estudada em ramos de 16 cultivares e seleções de baixa, média e alta necessidade de calor e 11 progênies oriundas de hibridações entre elas. Os ramos foram submetidos, previamente, a 2 ºC por 500 horas para satisfazer a necessidade de frio. O valor estimado da herdabilidade média para a necessidade de calor em gemas florais foi de 45% e 57%, em 1999 e 2000, respectivamente. Para gemas vegetativas, o valor estimado foi de 30%, em 1999. 'BR-1', 'Barbosa', 'Chula', 'Chinoca' e 'Eldorado' transmitem melhor o caráter necessidade de calor para as progênies do que os demais genótipos estudados. Os registros observados suportam um modelo de herança quantitativa com genes de maior efeito para menor necessidade de calor. A seleção de indivíduos com maior necessidade de calor para floração tende a retardar a floração sem, contudo, retardar com a mesma intensidade a época de brotação.

  8. Caloric stimulation with near infrared radiation does not induce paradoxical nystagmus.

    Science.gov (United States)

    Walther, L E; Asenov, D R; Di Martino, E

    2011-04-01

    Near infrared radiation can be used for warm stimulation in caloric irrigation of the equilibrium organ. Aim of this study was to determine whether near infrared radiation offers effective stimulation of the vestibular organ, whether it is well tolerated by the patients and especially whether it is a viable alternative to warm air stimulation in patients with defects of the tympanic membrane and radical mastoid cavities. Patients with perforations of the tympanic membrane (n = 15) and with radical mastoid cavities (n = 13) were tested both with near infrared radiation and warm dry air. A caloric-induced nystagmus could be seen equally effectively and rapidly in all patients. Contrary to stimulation with warm dry air, no paradoxical nystagmus was observed following caloric irrigation with a warm stimulus (near infrared radiation). Results of a questionnaire showed excellent patient acceptance of near infrared stimulation with no arousal effects or unpleasant feeling. In conclusion, near infrared radiation proved to be an alternative method of caloric irrigation to warm dry air in patients with tympanic membrane defects and radical mastoid cavities. Near infrared radiation is pleasant, quick, contact free, sterile and quiet. With this method an effective caloric warm stimulus is available. If near infrared radiation is used for caloric stimulus no evaporative heat loss occurs.

  9. Simulation studies of circular muscle contraction, longitudinal muscle shortening, and their coordination in esophageal transport.

    Science.gov (United States)

    Kou, Wenjun; Pandolfino, John E; Kahrilas, Peter J; Patankar, Neelesh A

    2015-08-15

    On the basis of a fully coupled active musculomechanical model for esophageal transport, we aimed to find the roles of circular muscle (CM) contraction and longitudinal muscle (LM) shortening in esophageal transport, and the influence of their coordination. Two groups of studies were conducted using a computational model. In the first group, bolus transport with only CM contraction, only LM shortening, or both was simulated. Overall features and detailed information on pressure and the cross-sectional area (CSA) of mucosal and the two muscle layers were analyzed. In the second group, bolus transport with varying delay in CM contraction or LM shortening was simulated. The effect of delay on esophageal transport was studied. For cases showing abnormal transport, pressure and CSA were further analyzed. CM contraction by itself was sufficient to transport bolus, but LM shortening by itself was not. CM contraction decreased the CSA and the radius of the muscle layer locally, but LM shortening increased the CSA. Synchronized CM contraction and LM shortening led to overlapping of muscle CSA and pressure peaks. Advancing LM shortening adversely influenced bolus transport, whereas lagging LM shortening was irrelevant to bolus transport. In conclusion, CM contraction generates high squeezing pressure, which plays a primary role in esophageal transport. LM shortening increases muscle CSA, which helps to strengthen CM contraction. Advancing LM shortening decreases esophageal distensibility in the bolus region. Lagging LM shortening no longer helps esophageal transport. Synchronized CM contraction and LM shortening seems to be most effective for esophageal transport.

  10. Palatable Hyper-Caloric Foods Impact on Neuronal Plasticity

    Science.gov (United States)

    Morin, Jean-Pascal; Rodríguez-Durán, Luis F.; Guzmán-Ramos, Kioko; Perez-Cruz, Claudia; Ferreira, Guillaume; Diaz-Cintra, Sofia; Pacheco-López, Gustavo

    2017-01-01

    Neural plasticity is an intrinsic and essential characteristic of the nervous system that allows animals “self-tuning” to adapt to their environment over their lifetime. Activity-dependent synaptic plasticity in the central nervous system is a form of neural plasticity that underlies learning and memory formation, as well as long-lasting, environmentally-induced maladaptive behaviors, such as drug addiction and overeating of palatable hyper-caloric (PHc) food. In western societies, the abundance of PHc foods has caused a dramatic increase in the incidence of overweight/obesity and related disorders. To this regard, it has been suggested that increased adiposity may be caused at least in part by behavioral changes in the affected individuals that are induced by the chronic consumption of PHc foods; some authors have even drawn attention to the similarity that exists between over-indulgent eating and drug addiction. Long-term misuse of certain dietary components has also been linked to chronic neuroimmune maladaptation that may predispose individuals to neurodegenerative conditions such as Alzheimer’s disease. In this review article, we discuss recent evidence that shows how consumption of PHc food can cause maladaptive neural plasticity that converts short-term ingestive drives into compulsive behaviors. We also discuss the neural mechanisms of how chronic consumption of PHc foods may alter brain function and lead to cognitive impairments, focusing on prenatal, childhood and adolescence as vulnerable neurodevelopmental stages to dietary environmental insults. Finally, we outline a societal agenda for harnessing permissive obesogenic environments. PMID:28261067

  11. [A shortened scale for overall, emotional and social loneliness].

    Science.gov (United States)

    de Jong Gierveld, J; van Tilburg, T

    2008-02-01

    Loneliness is an indicator of social well-being and pertains to the feeling of missing an intimate relationship (emotional loneliness) or missing a wider social network (social loneliness). The 11-item De Jong Gierveld scale has proved to be a valid and reliable measuring instrument for overall, emotional and social loneliness, although its length has sometimes rendered it difficult to use the scale in large surveys. In this study, we empirically tested a shortened version of the scale on data from two surveys (N=9448). Confirmatory factor analyses confirmed the specification of two latent factors. Congruent validity and the relationship with determinants (partner status, health) proved to be optimal. The 6-item De Jong Gierveld scale is a reliable and valid measuring instrument for overall, emotional and social loneliness, which is suitable for large surveys.

  12. AN IMPROVED OPTIMAL CHANNEL SHORTENING ALGORITHM FOR DMT MODULATION SYSTEMS

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In Discrete Multi-Tone (DMT) modulation systems, the well-known technique to overcome the Inter-Carrier Interference (ICI)/Inter-Symbol Interference (ISI) caused by the inadequate Cyclic Prefix (CP) length is to use a Time-Domain Equalizer (TDE) at the receiver front-end. An algorithm used to calculate the coefficients of the optimal shortening Time Domain Equalizer (TDE) was given by Melsa. However, this al gorithm requires that the length of the TDE must be smaller than or equal to the memory length of the target impulse response. This paper modifies this algorithm and makes it not only fit for calculating the coefficients of the TDE with arbitrary length, but also have a much less computational time.

  13. Force depression decays during shortening in the medial gastrocnemius of the rat.

    Science.gov (United States)

    Till, Olaf; Siebert, Tobias; Blickhan, Reinhard

    2014-03-21

    Force depression due to shortening of activated skeletal muscles has previously been described to be long lasting during isometric contractions following the shortening. In the present study, using the medial gastrocnemius of the rat, effects of force depression have been made apparent during shortening by computationally partially compensating for the direct effect of shortening velocity due to the tension-velocity relation. Evidence was found for the decay and complete disappearance of force depression already during continuation of the shortening contraction to short muscle lengths.

  14. Cortical T2 signal shortening in amyotrophic lateral sclerosis is not due to iron deposits

    Energy Technology Data Exchange (ETDEWEB)

    Hecht, M.J.; Neundoerfer, B. [University of Erlangen-Nurenberg, Department of Neurology, Erlangen (Germany); Fellner, C.; Fellner, F.A. [University of Erlangen-Nurenberg, Institute of Diagnostic Radiology, Erlangen (Germany); Landes-Nervenklinik Wagner-Jauregg, Institute of Radiology, Linz (Austria); Schmid, A. [University of Erlangen-Nurenberg, Institute of Diagnostic Radiology, Erlangen (Germany)

    2005-11-01

    Signal shortening of the motor cortex in T2-weighted MR images is a frequent finding in patients with amyotrophic lateral sclerosis (ALS). The cause of signal shortening in ALS is unknown, although iron deposits have been suggested. To test this hypothesis, we acquired T2*-weighted gradient-echo (GRE) MR images in addition to T2-weighted turbo spin-echo in 69 patients with ALS. Signal shortening in T2-weighted images was found in 31 patients. In T2*-weighted GRE images, only three patients had signal shortening. One patient with additional bifrontal haemorrhage had frontal but no motor cortex signal shortening. Iron deposits do not cause cortical signal shortening in patients with ALS predominantly. Other factors are presumably more important in the generation of cortical T2 shortening in ALS. (orig.)

  15. Effects of caloric vestibular stimulation on serotoninergic system in the media vestibular nuclei of guinea pigs

    Institute of Scientific and Technical Information of China (English)

    MA Fu-rong; LIU Jun-xiu; LI Xue-pei; MAO Jian-jun; ZHANG Qun-dan; JIA Hong-bo; MAO Lan-quan; ZHAO Rui

    2007-01-01

    Background Anatomic and electrophysiological studies have revealed that the neurons located in the media vestibular nuclei (MVN) receive most of the sensory vestibular input coming from the ipsilateral labyrinth and the responses of MVN neurons to caloric stimulation directly reflect changes in primary vestibular afferent activity. The aim of this study was to clarify the intrinsic characteristics of serotonin (5-hydroxytryptamine, 5-HT) release in the MVN during the period of vertigo induced by caloric stimulation.Methods We used an in vivo microdialysis technique to examine the effects of caloric stimulation on the serotoninergic system in MVN. Twenty four guinea pigs were randomly divided into the groups of irrigation of the ear canal with hot water (n=6), ice water (n=6) and 37℃ water (n=4), and the groups of irrigation of the auricle with hot water (n=4) and ice water (n=4), according to different caloric vestibular stimulation. We examined the animal's caloric nystagmus with a two-channel electronystagmographic recorder (ENG), and meanwhile examine serotonin (5-hydroxytryptamine, 5-HT) level in the MVN with microdialysis technique after caloric stimulation. Results In the caloric test the hot water (44℃) irrigation of the right external auditory canal induced horizontal nystagmus towards the right side lasting about 60 seconds and the ice water irrigation of the right external auditory canal induced it towards the left side lasting for about 90 seconds. No nystagmus was induced by 37℃ water irrigation of the external ear canal. Therefore, it was used as a negative control stimulation to the middle ear. The MVN 5-HT levels significantly increased in the first 5-minute collecting interval and increased to 254% and 189% of the control group in the second collecting interval in response to caloric vestibular stimulation with ice water and hot water respectively. The serotonin release was not distinctly changed by the irrigation of the auricle with ice water

  16. The Lexicocalorimeter: Gauging public health through caloric input and output on social media

    Science.gov (United States)

    Alajajian, Sharon E.; Williams, Jake Ryland; Reagan, Andrew J.; Alajajian, Stephen C.; Frank, Morgan R.; Mitchell, Lewis; Lahne, Jacob; Danforth, Christopher M.; Dodds, Peter Sheridan

    2017-01-01

    We propose and develop a Lexicocalorimeter: an online, interactive instrument for measuring the “caloric content” of social media and other large-scale texts. We do so by constructing extensive yet improvable tables of food and activity related phrases, and respectively assigning them with sourced estimates of caloric intake and expenditure. We show that for Twitter, our naive measures of “caloric input”, “caloric output”, and the ratio of these measures are all strong correlates with health and well-being measures for the contiguous United States. Our caloric balance measure in many cases outperforms both its constituent quantities; is tunable to specific health and well-being measures such as diabetes rates; has the capability of providing a real-time signal reflecting a population’s health; and has the potential to be used alongside traditional survey data in the development of public policy and collective self-awareness. Because our Lexicocalorimeter is a linear superposition of principled phrase scores, we also show we can move beyond correlations to explore what people talk about in collective detail, and assist in the understanding and explanation of how population-scale conditions vary, a capacity unavailable to black-box type methods. PMID:28187216

  17. A Biomechanical Model of the Inner Ear: Numerical Simulation of the Caloric Test

    Directory of Open Access Journals (Sweden)

    Shuang Shen

    2013-01-01

    Full Text Available Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  18. A biomechanical model of the inner ear: numerical simulation of the caloric test.

    Science.gov (United States)

    Shen, Shuang; Liu, Yingxi; Sun, Xiuzhen; Zhao, Wei; Su, Yingfeng; Yu, Shen; Liu, Wenlong

    2013-01-01

    Whether two vertical semicircular canals can receive thermal stimuli remains controversial. This study examined the caloric response in the three semicircular canals to the clinical hot caloric test using the finite element method. The results of the developed model showed the horizontal canal (HC) cupula maximally deflected to the utricle side by approximately 3 μm during the hot supine test. The anterior canal cupula began to receive the caloric stimuli about 20 s after the HC cupula, and it maximally deflected to the canal side by 0.55 μm. The posterior canal cupula did not receive caloric stimuli until approximately 40 s after the HC cupula, and it maximally deflected to the canal side by 0.34 μm. Although the endolymph flow and the cupular deformation change with respect to the head position during the test, the supine test ensures the maximal caloric response in the HC, but no substantial improvement for the responses of the two vertical canals was observed. In conclusion, while the usual supine test is the optimum test for evaluating the functions of the inner ear, more irrigation time is needed in order to effectively clinically examine the vertical canals.

  19. Mathematical modeling of the hormonal regulation of food intake and body weight : applications to caloric restriction and leptin resistance

    OpenAIRE

    Jacquier, Marine

    2016-01-01

    The regulation of food intake and energy expenditure usually limits important loss or gain of body weight. Hormones (leptin, ghrelin, insulin) and nutrients (glucose, triglycerides) are among the main regulators of food intake. Leptin is also involved in leptin resistance, often associated with obesity and characterized by a reduced efficacy to regulate food intake. Mathematical models describing the dynamics of body weight have been used to assist clinical weight loss interventions or to stu...

  20. Effects of Moderate Aerobic Exercise Combined With Caloric Restriction on Circulating Estrogens and IGF-1 in Premenopausal Women

    Science.gov (United States)

    2005-08-01

    Applied Anatomy & Physiology, Boston University, Boston, MA 1992-1996 Postdoctoral fellowship , University of Pittsburgh School of Medicine, Center...Menstrual Cycle: Psychological, sociological , and physiological factors. June, 5, 2003, Keynote for Society for Menstrual Cycle Research meeting...1992-1996 Postdoctoral Fellow: Center for the Study of Reproductive Physiology School of Medicine University of Pittsburgh Pittsburgh

  1. A distinct adipose tissue gene expression response to caloric restriction predicts 6-mo weight maintenance in obese subjects

    DEFF Research Database (Denmark)

    Mutch, D. M.; Pers, Tune Hannes; Temanni, M. R.

    2011-01-01

    AT) gene expression during a low-calorie diet (LCD) could be used to differentiate and predict subjects who experience successful short-term weight maintenance from subjects who experience weight regain. Design: Forty white women followed a dietary protocol consisting of an 8-wk LCD phase followed by a 6...

  2. Caloric restriction induces changes in insulin and body weight measurements that are inversely associated with subsequent weight regain

    DEFF Research Database (Denmark)

    Wong, Monica H T; Holst, Claus; Astrup, Arne;

    2012-01-01

    Successful weight maintenance following weight loss is challenging for many people. Identifying predictors of longer-term success will help target clinical resources more effectively. To date, focus has been predominantly on the identification of predictors of weight loss. The goal of the current...... study was to determine if changes in anthropometric and clinical parameters during acute weight loss are associated with subsequent weight regain....

  3. Efecto del calor aportado en recargues nanoestructurados base hierro

    Directory of Open Access Journals (Sweden)

    Agustín Gualco

    2013-12-01

    Full Text Available En los últimos años se han desarrollado consumibles de soldadura que depositan recubrimientos duros de aleaciones base hierro nanoestructuradas de gran resistencia al desgaste abrasivo. Las resistencias al desgaste erosivo y abrasivo están controladas principalmente por la composición química y la microestructura. A su vez, la microestructura del metal depositado puede presentar variaciones con el procedimiento de soldadura empleado, especialmente en relación al aporte térmico. Los parámetros operativos que definen el aporte térmico (tensión, corriente y velocidad de soldadura afectan aspectos como la geometría del cordón (ancho, penetración y sobremonta y la dilución con el material base. El propósito de este trabajo fue estudiar el efecto del calor aportado sobre las características geométricas del cordón, la dilución y la evolución microestructural de una aleación nanoestructurada base hierro, depositada por FCAW. Se soldaron muestras con aportes térmicos de entre 0,5 y 3,5 kJ/mm. Sobre cada cupón soldado se realizó un relevamiento dimensional, se analizó la composición química y se caracterizó la microestructura usando microscopías óptica y electrónica de barrido y difracción de rayos X. También se midieron la microdureza del depósito, el tamaño de cristalita y el grado de dilución. Se observó una gran influencia de las condiciones de proceso sobre la geometría del cordón. La dilución varió entre un 30 y un 40%, la microdureza del depósito se encontró entre 800 y 870 HV1 y el tamaño de cristalita osciló entre 105 y 130 nm, en función de las variables de proceso empleadas. Las mayores durezas y los menores tamaños de cristalita se obtuvieron con el menor aporte térmico, asociado a una menor dilución.

  4. Genetic Heterogeneity of HER2 Amplification and Telomere Shortening in Papillary Thyroid Carcinoma

    Directory of Open Access Journals (Sweden)

    Paola Caria

    2016-10-01

    Full Text Available Extensive research is dedicated to understanding if sporadic and familial papillary thyroid carcinoma are distinct biological entities. We have previously demonstrated that familial papillary thyroid cancer (fPTC cells exhibit short relative telomere length (RTL in both blood and tissues and that these features may be associated with chromosome instability. Here, we investigated the frequency of HER2 (Human Epidermal Growth Factor Receptor 2 amplification, and other recently reported genetic alterations in sporadic PTC (sPTC and fPTC, and assessed correlations with RTL and BRAF mutational status. We analyzed HER2 gene amplification and the integrity of ALK, ETV6, RET, and BRAF genes by fluorescence in situ hybridization in isolated nuclei and paraffin-embedded formalin-fixed sections of 13 fPTC and 18 sPTC patients. We analyzed BRAFV600E mutation and RTL by qRT-PCR. Significant HER2 amplification (p = 0.0076, which was restricted to scattered groups of cells, was found in fPTC samples. HER2 amplification in fPTCs was invariably associated with BRAFV600E mutation. RTL was shorter in fPTCs than sPTCs (p < 0.001. No rearrangements of other tested genes were observed. These findings suggest that the association of HER2 amplification with BRAFV600E mutation and telomere shortening may represent a marker of tumor aggressiveness, and, in refractory thyroid cancer, may warrant exploration as a site for targeted therapy.

  5. Restrictions and Proportionality

    DEFF Research Database (Denmark)

    Werlauff, Erik

    2009-01-01

    The article discusses three central aspects of the freedoms under European Community law, namely 1) the prohibition against restrictions as an important extension of the prohibition against discrimination, 2) a prohibition against exit restrictions which is just as important as the prohibition...... against host country restrictions, but which is often not recognised to the same extent by national law, and 3) the importance of also identifying and recognising an exit restriction, so that it is possible to achieve the required test of appropriateness and proportionality in relation to the rule...

  6. Contraction-specific differences in maximal muscle power during stretch-shortening cycle movements in elderly males and females

    DEFF Research Database (Denmark)

    Caserotti, Paolo; Aagaard, Per; Simonsen, Erik Bruun;

    2001-01-01

    Aging, muscle power, stretch-shortening cycle, eccentric muscle actions, concentric contractions......Aging, muscle power, stretch-shortening cycle, eccentric muscle actions, concentric contractions...

  7. Determinación del calor de fraguado de cemento por icrocalorimetría

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se determina el calor de fraguado del cemento Río Claro tipo III (Río Claro, Antioquia, Colombia por microcalorimetría de conducción de calor; así como también los efectos de la glucosa y de la sacarosa en el proceso de fraguado de este material. Al emplear 0,15 y 0,05% ( % en peso de estos aditivos en la preparación de las pastas, se observan retardos considerables en el fraguado de las mismas. Los aditivos también modifican el calor de fraguado: la pasta libre de estos presenta un valor de 38,03 J/g en tanto que la adición de glucosa y sacarosa producen valores menores, excepto en el caso de la sacarosa al 0,05% donde se observa un efecto térmico de 55.80 J/s,

  8. Magneto-Caloric Effect of Gd5Si2Ge2Compounds under Different Processing Conditions

    Institute of Scientific and Technical Information of China (English)

    Zeng Hong; Yue Ming; Niu Peili; Zhang Jiuxing

    2004-01-01

    The magneto-caloric effect of Gd5 Si2Ge2 compounds produced by various techniques is investigated in terms of their magnetization behaviors in the magnetic field from 0 to 2.0 T.The studied materials include arc-melted, annealed and sintered alloys.The results demonstrate that the Gd5Si2Ge2 alloys obtained under different processing conditions possess distinct magneto-caloric effect due to their various microstructures.Proper annealing treatment can enhance the magneto-caloric effect of the alloy remarkably.While the sintered alloy bears relatively lower value of magnetic entropy change ( △ SM) than arc-melted one.The magnetic entropy change of the annealed Gd5 Si2Ge2 alloy arrives the arrives the maximum value of - △SM = 15.29 J· kg-1· K-1 for magnetic field change under 2.0 T in the present work.

  9. Effect of gravity on the caloric stimulation of the inner ear

    Science.gov (United States)

    Kassemi, Mohammad; Deserranno, Dimitri; Oas, John G.

    2004-01-01

    Robert Barany won the 1914 Nobel Prize in medicine for his convection hypothesis for caloric stimulation. Microgravity caloric tests aboard the 1983 SpaceLab 1 mission produced nystagmus results that contradicted the basic premise of Barany's convection theory. In this paper, we present a fluid structural analysis of the caloric stimulation of the lateral semicircular canal. Direct numerical simulations indicate that on earth, natural convection is the dominant mechanism for endolymphatic flow. However, in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, an expansive convection becomes the sole mechanism for producing endolymph motion and cupular displacement. Transient 1 g and microgravity case studies are presented to delineate the different dynamic behaviors of the 1 g and microgravity endolymphatic flows. The associated fluid-structural interactions are also analyzed based on the time evolution of cupular displacements.

  10. Efecte de l'estrès per calor en cabres productores de llet

    OpenAIRE

    Salama, Ahmed A. K.

    2015-01-01

    A causa del canvi climàtic, s'espera una major freqüència i intensitat de les onades de calor en el futur. Una investigació ha estudiat els efectes de l'estrès per calor sobre la producció de cabres lleteres de raça Murciano-Granadina i els efectes de l'addició de l'oli de soja i del propilenglicol a la seva dieta. Els resultats mostren diferències evidents en les característiques de la llet de les cabres sotmeses a estrès per calor, així com beneficis de l'ús d'oli de soja per millorar les p...

  11. Ten-Year Trends in Children’s Caloric-Beverage Consumption and Behavioral Intent

    OpenAIRE

    Carnot MJ; Sutliffe JT; Palmer. SE; Elliott E

    2015-01-01

    Soft drinks, fruit juice and milk are the most common caloric-beverages consumed by adolescents and teens. We report the ten-year trends in the percentage of daily calories consumed in the form of caloric-beverages from a broad sample of fifth-grade students in the United States. This is a major area of concern related to dietary quality and body weight amongst children. The study was conducted from 2001-2011 through the Healthy Hearts for Kids (HH4K) online instructional ...

  12. Changes of endolymphatic pressure in the semicircular canal of pigeon by caloric stimulation

    Science.gov (United States)

    Wada, Y.; Suzuki, H.; Watanabe, S.

    1994-08-01

    It gets into difficult to explain the mechanism of caloric nystagmus only by convection theory from results of microgravity experiments. One of the other theories is an occurrence of a relative volume change due to a temperature change. Since the volume change must lead to a pressure change after caloric stimulation, we tried to measure the ampulla pressure of the horizontal semicircular canal in pigeons (Columba livia) using an improved servo micropipette system. The main result was that the ampulla pressure increased by cooling and decreased by heating. The changes of the ampulla pressure depended on the temperature change but were not influenced by the pigeon's head position.

  13. Aprofitant cada engruna de calor : el Tub Verd de Mataró

    OpenAIRE

    Alerm, Llorenç

    2012-01-01

    La calor residual de diverses infraestructures mediambientals permet distribuir calor i fred al seu entorn urbà. Es tracta d’un aprofitament energètic que redueix contaminació, emissions de CO2 i importacions de combustible. Una estratègia que fa anys que funciona a diversos països del món: al centre i nord d’Europa fa temps que hi està força estesa, i més recentment ha arribat aquí, amb iniciatives com la del Tub Verd de Mataró.

  14. Second Law Violation By Magneto-Caloric Effect Adiabatic Phase Transition of Type I Superconductive Particles

    Directory of Open Access Journals (Sweden)

    Peter Keefe

    2004-03-01

    Full Text Available Abstract: The nature of the thermodynamic behavior of Type I superconductor particles, having a cross section less than the Ginzburg-Landau temperature dependent coherence length is discussed for magnetic field induced adiabatic phase transitions from the superconductive state to the normal state. Argument is advanced supporting the view that when the adiabatic magneto-caloric process is applied to particles, the phase transition is characterized by a decrease in entropy in violation of traditional formulations of the Second Law, evidenced by attainment of a final process temperature below that which would result from an adiabatic magneto-caloric process applied to bulk dimensioned specimens.

  15. Absence of rotation perception during warm water caloric irrigation in some seniors with postural instability

    Directory of Open Access Journals (Sweden)

    Elodie eChiarovano

    2016-01-01

    Full Text Available Falls in seniors are a major public health problem. Falls lead to fear of falling, reduced mobility and decreased quality of life. Vestibular dysfunction is one of the fall risk factors. The relationship between objective measures of vestibular responses and age has been studied. However, the effects of age on vestibular perception during caloric stimulation have not been studied.Twenty senior subjects were included in the study separated in two groups: 10 seniors reporting postural instability (PI and exhibiting absence of vestibular perception when they tested with caloric stimulation and 10 sex and age-matched seniors with no such problems (controls. We assessed vestibular perception on a binary rating scale during the warm irrigation of the caloric test. The function of the various vestibular receptors was assessed using video-head impulse test (vHIT, caloric tests, and cervical and ocular VEMPs. The Equitest was used to evaluate balance. No horizontal canal dysfunction assessed using both caloric test and vHIT was detected in either group. No significant difference was detected between PI and control groups for the peak SPV of caloric induced ocular nystagmus or for the HVOR gain. All of the controls perceived rotation when the maximal SPV during warm irrigation was equal to or greater than 15°/s. None of the subjects in the PI group perceived rotation even while the peak SPV exceeded 15°/s, providing objective evidence of normal peripheral horizontal canal function. All of the PI group had abnormal Equitest results, particularly in the two last conditions.These investigations show for the first time that vestibular perception can be absent during a caloric test despite normal horizontal canal function. We call this dissociation vestibular neglect. Patients with poor vestibular perception may not be aware of postural perturbations and so will not correct for them. Thus, falls in the elderly may result, amongst other factors, from a

  16. Modelamiento y simulación de tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  17. Modelamiento y simulación de un tubo de calor de alta temperatura

    OpenAIRE

    Guerra del Río, César Fabián

    2013-01-01

    Resumen: La tecnología de tubos de calor de alta temperatura permite recuperar la energía residual de procesos industriales que día a día se ven obligados a comprometerse en la solución de importantes limitaciones como la contaminación de gases efluentes, perdida deliberada de energía a los alrededores, limitación en el espacio físico para mejorar el proceso y aumento indiscriminado de los costos de inversión. Sin embargo, los tubos de calor de alta temperatura, presentan limitaciones en su f...

  18. Caloric Intake From Fast Food Among Children and Adolescents in the United States, 2011-2012.

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D; Ogden, Cynthia L

    2015-09-01

    Consumption of fast food has been linked to weight gain in adults (1). Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents (2). From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years (3). This report presents the most recent data on the percentage of calories consumed from fast food among U.S. children by sex, age group, race and Hispanic origin, poverty status, and weight status.

  19. Shortening a Patient Experiences Survey for Medical Homes

    Directory of Open Access Journals (Sweden)

    Judy H. Ng

    2015-12-01

    Full Text Available The Consumer Assessment of Healthcare Providers and Systems—Patient-Centered Medical Home (CAHPS PCMH Survey assesses patient experiences reflecting domains of care related to general patient experience (access to care, communication with providers, office staff interaction, provider rating and PCMH-specific aspects of patient care (comprehensiveness of care, self-management support, shared decision making. The current work compares psychometric properties of the current survey and a proposed shortened version of the survey (from 52 to 26 adult survey items, from 66 to 31 child survey items. The revisions were based on initial psychometric analysis and stakeholder input regarding survey length concerns. A total of 268 practices voluntarily submitted adult surveys and 58 submitted child survey data to the National Committee for Quality Assurance in 2013. Mean unadjusted scores, practice-level item and composite reliability, and item-to-scale correlations were calculated. Results show that the shorter adult survey has lower reliability, but still it still meets general definitions of a sound survey for the adult version, and resulted in few changes to mean scores. The impact was more problematic for the pediatric version. Further testing is needed to investigate approaches to improving survey response and the relevance of survey items in informing quality improvement.

  20. The different muscle-energetics during shortening and stretch.

    Science.gov (United States)

    Jarosch, Robert

    2011-01-01

    The helical shape of the thin filaments causes their passive counterclockwise rotation during muscle stretch that increases tensile stress and torque at first by unwinding and then by winding up the four anchoring Z-filaments. This means storage of energy in the series elastic Z-filaments and a considerable decrease of the liberated energy of heat and work to (h-w(ap)), where h is the heat energy and w(ap) the stretch energy induced from outside by an apparatus. The steep thin filament helix with an inclination angle of 70° promotes the passive rotation during stretch, but impedes the smooth sliding of shortening by increased friction and production of frictional heat. The frictional heat may be produced by the contact with the myosin cross-bridges: (1) when they passively snap on drilling thin filaments from cleft to cleft over a distance 2 × 2.7 nm = 5.4 nm between the globular actin monomers in one groove, causing stepwise motion; or (2) when they passively cycle from one helical groove to the next (distance 36 nm). The latter causes more heat and may take place on rotating thin filaments without an effective forward drilling ("idle rotation"), e.g., when they produce "unexplained heat" at the beginning of an isometric tetanus. In an Appendix to this paper the different states of muscle are defined. The function of its most important components is described and rotation model and power-stroke model of muscular contraction is compared.

  1. Chemical Sharpening, Shortening, and Unzipping of Boron Nitride Nanotubes

    Science.gov (United States)

    Liao, Yunlong; Chen, Zhongfang; Connell, John W.; Fay, Catharine C.; Park, Cheol; Kim, Jae-Woo; Lin, Yi

    2014-01-01

    Boron nitride nanotubes (BNNTs), the one-dimensional member of the boron nitride nanostructure family, are generally accepted to be highly inert to oxidative treatments and can only be covalently modifi ed by highly reactive species. Conversely, it is discovered that the BNNTs can be chemically dispersed and their morphology modifi ed by a relatively mild method: simply sonicating the nanotubes in aqueous ammonia solution. The dispersed nanotubes are significantly corroded, with end-caps removed, tips sharpened, and walls thinned. The sonication treatment in aqueous ammonia solution also removes amorphous BN impurities and shortened BNNTs, resembling various oxidative treatments of carbon nanotubes. Importantly, the majority of BNNTs are at least partially longitudinally cut, or "unzipped". Entangled and freestanding BN nanoribbons (BNNRs), resulting from the unzipping, are found to be approximately 5-20 nm in width and up to a few hundred nanometers in length. This is the fi rst chemical method to obtain BNNRs from BNNT unzipping. This method is not derived from known carbon nanotube unzipping strategies, but is unique to BNNTs because the use of aqueous ammonia solutions specifi cally targets the B-N bond network. This study may pave the way for convenient processing of BNNTs, previously thought to be highly inert, toward controlling their dispersion, purity, lengths, and electronic properties.

  2. Leg stiffness modulation during exhaustive stretch-shortening cycle exercise.

    Science.gov (United States)

    Kuitunen, S; Kyröläinen, H; Avela, J; Komi, P V

    2007-02-01

    The present study examined the effects of muscle activity modulation on leg stiffness during an exhaustive stretch-shortening cycle (SSC) exercise in eight male subjects. Reaction force, electromyography (EMG) of the soleus (Sol), gastrocnemius (Ga) and vastus lateralis (VL) muscles and sledge seat position were recorded during the SSC exercise, consisting of 100 maximal intermittent drop jumps followed by a continuous submaximal jumping until exhaustion, on a sledge apparatus. Metabolic loading was determined by measuring blood lactate (La). No change was found in leg stiffness during the maximal jumps, whereas the subsequent submaximal jumping induced a significant reduction by 27+/-12% (PEMG ratio between the braking and push-off phases in Sol (r=0.81, PEMG ratio at the end of the submaximal jumping in Sol (r=-0.88, Pmodulation between the braking and push-off phases in the triceps surae muscle, particularly in Ga, plays an important role in leg stiffness adjustments during fatiguing SSC exercise. It is suggested that efficient activity modulation (i.e. high EMG ratio) of the triceps surae muscle during an intensive fatiguing SSC exercise may postpone the exhaustion and development of metabolic fatigue.

  3. Does the speed of shortening affect steady-state force depression in cat soleus muscle?

    Science.gov (United States)

    Leonard, T R; Herzog, W

    2005-11-01

    It has been stated repeatedly for the past 50 years that the steady-state force depression following shortening of an activated muscle depends on the speed of shortening. However, these statements were based on results from experiments in which muscles were shortened at different speeds but identical activation levels. Therefore, the force during shortening was changed in accordance with the force-velocity relationship of muscles: that is, increasing speeds of shortening were associated with decreasing forces, and vice versa. Consequently, it is not possible at present to distinguish whether force depression is caused by the changes in speed, as frequently stated, or the associated changes in force, or both. The purpose of this study was to test if force depression depends on the speed of shortening. We hypothesized that force depression was dependent on the force but not the speed of contraction. Our prediction is that the amount of force depression after shortening contractions at different speeds could be similar if the force during contraction was controlled at a similar level. Cat soleus muscles (n=7) were shortened by 9 or 12 mm at speeds of 3, 9, and 27 mm/s, first with a constant activation during shortening (30Hz), then with activation levels that were reduced (shortening forces of the fast speed contractions (27 mm/s). If done properly, force depression could be precisely matched at the three different speeds, indicating that force depression was related to the force during the shortening contraction but not to the speed. However, in order to match force depression, the forces during shortening had to be systematically greater for the slow compared to the fast speeds of shortening, suggesting that force depression also depends on the level of activation, as force depression at constant activation levels can only be matched if the force during shortening, evaluated by the mechanical work, is identical. Therefore, we conclude that force depression depends

  4. Effect of Replacing Sugar with Non-Caloric Sweeteners in Beverages on the Reward Value after Repeated Exposure

    NARCIS (Netherlands)

    Griffioen-Roose, S.; Smeets, P.A.M.; Weijzen, P.L.G.; Rijn, van I.; Bosch, van den I.; Graaf, de C.

    2013-01-01

    Background: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. Objective: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty d

  5. Differential effects of fasting vs food restriction on liver thyroid hormone metabolism in male rats.

    Science.gov (United States)

    de Vries, E M; van Beeren, H C; Ackermans, M T; Kalsbeek, A; Fliers, E; Boelen, A

    2015-01-01

    A variety of illnesses that leads to profound changes in the hypothalamus-pituitary-thyroid (HPT) are axis collectively known as the nonthyroidal illness syndrome (NTIS). NTIS is characterized by decreased tri-iodothyronine (T3) and thyroxine (T4) and inappropriately low TSH serum concentrations, as well as altered hepatic thyroid hormone (TH) metabolism. Spontaneous caloric restriction often occurs during illness and may contribute to NTIS, but it is currently unknown to what extent. The role of diminished food intake is often studied using experimental fasting models, but partial food restriction might be a more physiologically relevant model. In this comparative study, we characterized hepatic TH metabolism in two models for caloric restriction: 36 h of complete fasting and 21 days of 50% food restriction. Both fasting and food restriction decreased serum T4 concentration, while after 36-h fasting serum T3 also decreased. Fasting decreased hepatic T3 but not T4 concentrations, while food restriction decreased both hepatic T3 and T4 concentrations. Fasting and food restriction both induced an upregulation of liver D3 expression and activity, D1 was not affected. A differential effect was seen in Mct10 mRNA expression, which was upregulated in the fasted rats but not in food-restricted rats. Other metabolic pathways of TH, such as sulfation and UDP-glucuronidation, were also differentially affected. The changes in hepatic TH concentrations were reflected by the expression of T3-responsive genes Fas and Spot14 only in the 36-h fasted rats. In conclusion, limited food intake induced marked changes in hepatic TH metabolism, which are likely to contribute to the changes observed during NTIS.

  6. 山嵛酸低热量油脂的可用热量及安全性评价%Evaluation on Caloric Availability and Safety of Reduced-calorie Fat Containing Behenic Acid

    Institute of Scientific and Technical Information of China (English)

    刘如灿; 金青哲; 单良; 王兴国

    2011-01-01

    以葵花籽油为标准进行21 d的大鼠生长试验,评价了含30%山嵛酸的低热量油脂的可用热量,得到其可用热量为25.8 kJ/g,与葵花籽油37.8 kJ/g相比降低了31.75%.添加5%、15%山嵛酸低热量油脂中未被吸收的山嵛酸分别为73.53%和81.24%.动物试验结果表明,山嵛酸低热量油脂对大鼠血清中的TG、TC、HDL-C、LDL-C以及AI值和AII值的影响与葵花籽油类似,不会升高发生动脉硬化的风险.%The caloric availability of reduced - calorie fat containing behenic acid was estimated by a restricted diet growth experiment over 21 d on SD rats with sunflower seed oil as a caloric control. The result showed that the caloric availability of the reduced - calorie fat containing 30% behenic acid was 25. 8 kj/g. Compared with sunflower seed oil,the caloric availability decreased by 31.75%.The unabsorption behenic acid added with 5% and 30% reduced - calorie fat containing behenic acid were respectively 73.53% and 81.24%. The serum lipid levels of rats before and after experiments showed that effects of reduced -calorie fat on serum lipid levels,such as TG,TC,HDL-C, LDL-C,AI and All,were similar to the sunflower seed oil,and the risk of atherosclerosis was not increased.

  7. Circular smooth muscle contributes to esophageal shortening during peristalsis

    Institute of Scientific and Technical Information of China (English)

    Anil K Vegesna; Keng-Yu Chuang; Ramashesai Besetty; Steven J Phillips; Alan S Braverman; Mary F Barbe; Michael R Ruggieri

    2012-01-01

    AIM:To study the angle between the circular smooth muscle (CSM) and longitudinal smooth muscle (LSM) fibers in the distal esophagus.METHODS:In order to identify possible mechanisms for greater shortening in the distal compared to proximal esophagus during peristalsis,the angles between the LSM and CSM layers were measured in 9 cadavers.The outer longitudinal layer of the muscularis propria was exposed after stripping the outer serosa.The inner circular layer of the muscularis propria was then revealed after dissection of the esophageal mucosa and the underlying muscularis mucosa.Photographs of each specimen were taken with half of the open esophagus folded back showing both the outer longitudinal and inner circular muscle layers.Angles were measured every one cm for 10 cm proximal to the squamocolumnar junction (SCJ) by two independent investigators.Two human esophagi were obtained from organ transplant donors and the angles between the circular and longitudinal smooth muscle layers were measured using micro-computed tomography (micro CT) and Image J software.RESULTS:All data are presented as mean ± SE.The CSM to LSM angle at the SCJ and 1 cm proximal to SCJ on the autopsy specimens was 69.3 ± 4.62 degrees vs 74.9 ± 3.09 degrees,P =0.32.The CSM to LSM angle at SCJ were statistically significantly lower than at 2,3,4 and 5 cm proximal to the SCJ,69.3 ± 4.62 degrees vs 82.58 ± 1.34 degrees,84.04 ± 1.64 degrees,84.87 ± 1.04 degrees and 83.72 ± 1.42 degrees,P =0.013,P =0.008,P =0.004,P =0.009 respectively.The CSM to LSM angle at SCJ was also statistically significantly lower than the angles at 6,7 and 8 cm proximal to the SCJ,69.3 ± 4.62 degrees vs 80.18 ± 2.09 degrees,81.81 ± 1.75 degrees and 80.96 ± 2.04 degrees,P =0.05,P =0.02,P =0.03 respectively.The CSM to LSM angle at 1 cm proximal to SCJ was statistically significantly lower than at 3,4 and 5 cm proximal to the SCJ,74.94 ± 3.09 degrees vs 84.04 ± 1.64 degrees,84.87± 1.04 degrees and 83.72 ± 1

  8. GPS computer navigators to shorten EMS response and transport times.

    Science.gov (United States)

    Ota, F S; Muramatsu, R S; Yoshida, B H; Yamamoto, L G

    2001-05-01

    GPS (global positioning satellite system to determine one's position on earth) units have become inexpensive and compact. The purpose of this study is to assess the effectiveness of a GPS enhanced computer street map navigator to improve the ability of EMS drivers in an urban setting to locate their destination and shorten response times. For part I, residential addresses in the city were randomly selected from a telephone directory. Two driver/navigator teams were assigned to drive to the address adhering to speed limits. One team used a standard street map, whereas the other team used a GPS computer navigator. The travel time and distance of the runs were compared. For part II, the computer GPS navigator was placed on an ambulance to supplement their normal methods of navigation to find the address requesting EMS. After the run was completed, EMS providers were interviewed to determine their opinion of whether the GPS navigator was helpful. For part I the results showed that in the 29 initial test runs, comparing the GPS team versus the standard map team, the mean distances traveled were 8.7 versus 9.0 kilometers (not significant) and the mean travel times were 13.5 versus 14.6 minutes (P=.02), respectively. The GPS team arrived faster in 72% runs. For part II the results showed that most EMS providers surveyed noted that the GPS computer navigator enhanced their ability to find the destination and all EMS providers acknowledged that it would enhance their ability to find a destination in an area in which they were unfamiliar. These results suggest that a portable GPS computer navigator system is helpful and can enhance the ability of prehospital care providers to locate their destination. Because these units are accurate and inexpensive, GPS computer navigators may be a valuable tool in reducing pre-hospital transport times.

  9. Resource availability hypothesis: Perceived financial and caloric status affect individuals' height preferences for potential partners.

    Science.gov (United States)

    Sun, Qingzhou; Lou, Liandi; Lu, Jingyi; Wang, Xiaoming; Zhong, Jun; Tan, Xuyun; Li, Yanxia; Liu, Yongfang

    2016-10-01

    Height is an important concern in human mate choices. Prior research indicates that people who live in areas with abundant resources differ from those who live in areas with scarce resources regarding height preferences. Based on a health-maximizing principle, we propose a resource availability account for such differences. Compared with women's height preferences, men's height preferences are hypothesized to be more dependent on either financial or caloric resource availability. Specifically, taller females would be more preferred by males who are poor in resources than those who are rich in resources. Results from three studies supported these hypotheses. In Study 1, men from remote areas of China who had lower family income preferred taller women more than those from eastern China who had higher family income. In Study 2, men who were financially dissatisfied preferred taller women more than those who were financially satisfied. In Study 3, men with low caloric status preferred taller women more than men with high caloric status. In addition, women's height preferences in Studies 1, 2 and 3 were less determined by resource availability. These findings suggest that height preferences are changeable, depending on financial or caloric status.

  10. A critique of Sadi Carnot's work and a mathematical theory of the caloric

    CERN Document Server

    Dass, N D Hari

    2013-01-01

    In this work, Sadi Carnot;s fundamental work is critically examined, and contrasted with modern thermodynamics. A mathematical theory of his work is given on the basis of the observation that in caloric theory dQ is a perfect differential.

  11. Biochemical composition and caloric potential of zooplankton from Bay of Bengal

    Digital Repository Service at National Institute of Oceanography (India)

    Sreepada, R.A.; Rivonker, C.U.; Parulekar, A.H.

    .62, 4.95, 1.54, 0.43, 4.4 and 4.16 respectively on wet weight basis. A good correlation of caloric potential with protein and lipid indicated to a certain extent that protein and lipid act as metabolic reserves of the zooplankton in the area...

  12. Timing versus caloric goal in nutritional therapy for critically ill patients

    Directory of Open Access Journals (Sweden)

    Oellen Stuani Franzosi

    Full Text Available Introduction: Enteral nutrition is an important therapy for severely critically ill patients. The timing and amount of energy have been highly debated. Objective: The aim of the present study was to directly compare the timing and the caloric targets in critically ill patients. Methods: Retrospective cohort study conducted at a single center, comparing timing and caloric goal for critically ill patients. Patients were stratified according to the start of nutritional therapy (24, 48, or more than 48 h and the amount of energy delivered (target adequacy of previously calculated percentage in the first week. Statistical analysis was performed using parametric and non-parametric tests for independent samples and logistic regression. The results were expressed as mean ± standard deviation or incidence and percentage. Results and discussion: There were no differences in major clinical outcomes in relation to the achievement of percentage of caloric goal at the end of the first week of the study. The beginning of caloric intake on the first day of hospitalization was associated with reduced mortality in the intensive care unit, but not with hospital mortality. The strategy of an early and limited amount of calories seems to be associated with a better outcome. Prospective studies evaluating and comparing these strategies are recommended.

  13. Caloric density of Loricariichthys platymetopon (Osteichthyes, Loricariidae in the Upper Paraná River floodplain, Brazil

    Directory of Open Access Journals (Sweden)

    Daniela Aparecida Garcia

    2010-10-01

    Full Text Available This study analyzed the muscle energy content (caloric density of L. platymetopon captured at different sites of the Upper Paraná River floodplain, and potential relationships between the content and various environmental variables (water temperature, oxygen dissolved in water, food availability, relative numeric abundance and biological variables (body size and reproductive cycle. Quarterly samplings from September 2006 to June 2007 in the lakes and rivers resulted in a sample of 739 specimens, whose muscle caloric density was determined using a calorimeter. Differences between the caloric averages of the males and females and among the different stages of gonadal development were not significant. Caloric density varied over time and space, with two seasonal variation trends. The intensity of the correlation between the caloric density and each environmental variable, as well as the type of correlation, varied according to the sampled site. Body size and reproductive cycle were not correlated with caloric density.Este estudo analisou o conteúdo de energia (densidade calórica de L. platymetopon capturados em diferentes locais da planície alagável do Alto Rio Paraná, e potenciais relações entre este conteúdo e várias variáveis ambientais (temperatura da água, oxigênio dissolvido na água, disponibilidade de alimento, abundância relativa numérica e variáveis biológicas (tamanho corpóreo e ciclo reprodutivo. Coletas trimestrais, de setembro/2006 a junho/2007, em lagos e rios, resultaram em uma amostra de 739 espécimes, cuja densidade calórica muscular foi determinada através de calorímetro. Diferenças entre as médias calóricas de machos e fêmeas e entre os estádios de desenvolvimento gonadal não foram significativas Densidade calórica variou sazonal e espacialmente, com duas tendências de variação sazonal. A intensidade da correlação entre densidade calórica e cada variável e cada variável ambiental, assim como

  14. Shortening-induced torque depression in old men: implications for age-related power loss.

    Science.gov (United States)

    Power, Geoffrey A; Makrakos, Demetri P; Stevens, Daniel E; Herzog, Walter; Rice, Charles L; Vandervoort, Anthony A

    2014-09-01

    Following active muscle shortening, the steady-state isometric torque at the final muscle length is lower than the steady-state torque obtained for a purely isometric contraction at that same final muscle length. This well-documented property of skeletal muscle is termed shortening-induced torque depression (TD). Despite many investigations into the mechanisms of weakness and power loss in old age, the influence of muscle shortening on the history dependence of isometric torque production remains to be elucidated. Thus, it is unclear whether older adults are disadvantaged for torque and power production following a dynamic shortening contraction. The purpose of this study was to evaluate shortening-induced TD in older adults, and to determine whether shortening-induced TD is related to power loss. Maximal voluntary isometric dorsiflexion contractions (MVC; 10s) in 8 young (25.5±3.7years) and 9 old (76.1±5.4years) men were performed on a HUMAC NORM dynamometer as a reference, and then again following an active shortening of 40° joint excursion (40°PF-0°PF) at angular velocities of 15°/s and 120°/s. Work and instantaneous power were derived during shortening. Shortening-induced TD was calculated and expressed as a percentage by determining the mean torque value over 1s during the isometric steady state of the MVC following shortening, divided by the mean torque value for the same 1s time period during the isometric reference MVC. To assess muscle activation, electromyography (root mean square; EMGRMS) of the tibialis anterior (TA) and soleus (SOL) was calculated at identical time points used in assessing shortening-induced TD, and voluntary activation (VA) was assessed using the interpolated twitch technique. Old were 18% weaker than young for MVC, and ~40% less powerful for 15°/s and 120°/s of shortening. Old produced 37% and 21% less work for 15°/s and 120°/s than young, respectively. Furthermore, old experienced 60% and 70% greater shortening-induced TD

  15. Effects of stretch and shortening on gene expression in intact myocardium.

    Science.gov (United States)

    Haggart, Charles R; Ames, Elizabeth G; Lee, Jae K; Holmes, Jeffrey W

    2014-01-15

    Multiple cues have been suggested as the mechanical stimulus for the heart's hypertrophic response. Our work has previously suggested that the amount of cyclic shortening in cardiomyocytes controls myocyte shape and the amount of stretch controls myocyte size. To identify gene expression changes that occur in response to these mechanical perturbations, we used microarray analysis of papillary muscles cultured for 12 h at physiological or reduced levels of cyclic shortening and physiological or reduced mean stretch. Overall, genes related to extracellular matrix (ECM) were surprisingly prominent in our analysis. Connective tissue growth factor was among a small group of genes regulated by the amount of cyclic shortening regardless of the level of mean stretch, and many more ECM genes were regulated by shortening with reduced amounts of stretch. When we compared our results to gene expression data from an in vivo model of pressure overload (PO), which also decreases myocyte shortening, we found the genes that were commonly regulated in PO and our decreased shortening groups were most significantly enriched for ontology terms related to the ECM, followed by genes associated with mechanosensing and the cytoskeleton. The list of genes regulated in PO and our decreased shortening groups also includes genes known to change early in hypertrophy, such as myosin heavy chain 7, brain natriuretic peptide, and myosin binding protein C. We conclude that in intact myocardium, the amount of cyclic shortening may be an important regulator not only of myocyte genes classically associated with hypertrophy but also of ECM genes.

  16. Accumulating evidence for increased velocity of airway smooth muscle shortening in asthmatic airway hyperresponsiveness.

    Science.gov (United States)

    Ijpma, Gijs; Matusovsky, Oleg; Lauzon, Anne-Marie

    2012-01-01

    It remains unclear whether airway smooth muscle (ASM) mechanics is altered in asthma. While efforts have originally focussed on contractile force, some evidence points to an increased velocity of shortening. A greater rate of airway renarrowing after a deep inspiration has been reported in asthmatics compared to controls, which could result from a shortening velocity increase. In addition, we have recently shown in rats that increased shortening velocity correlates with increased muscle shortening, without increasing muscle force. Nonetheless, establishing whether or not asthmatic ASM shortens faster than that of normal subjects remains problematic. Endobronchial biopsies provide excellent tissue samples because the patients are well characterized, but the size of the samples allows only cell level experiments. Whole human lungs from transplant programs suffer primarily from poor patient characterization, leading to high variability. ASM from several animal models of asthma has shown increased shortening velocity, but it is unclear whether this is representative of human asthma. Several candidates have been suggested as responsible for increased shortening velocity in asthma, such as alterations in contractile protein expression or changes in the contractile apparatus structure. There is no doubt that more remains to be learned about the role of shortening velocity in asthma.

  17. Compatibility of selected plant-based shortening as lard substitute: microstructure, polymorphic forms and textural properties

    Directory of Open Access Journals (Sweden)

    N. A.M. Yanty

    2017-03-01

    Full Text Available A study was carried out to determine the compatibility of three plant-based shortening mixtures to lard shortening (LD in terms of microstructure, polymorphic forms, and textural properties. The shortenings of binary, ternary, and quaternary fat mixtures were prepared according to a standard procedure by blending mee fat (MF with palm stearin (PS in a 99:1 (w/w ratio; avocado fat (Avo with PS and cocoa butter (CB in a 84:7:9 (w/w ratio; palm oil (PO with PS, soybean oil (SBO and CB in a 38:5:52:5 (w/w ratio, respectively. The triacylglycerol composition, polymorphic forms, crystal morphology, and textural properties of the shortening were evaluated. This study found that all three plant-based shortenings and LD shortening were similar with respect to their consistency, hardness and compression and adhesiveness values. However, all plant-based shortening was found to be dissimilar to LD shortening with respect to microstructure.

  18. Limb shortening in the course of solitary bone cyst treatment - a comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, Maciej [Karol Marcinkowski University of Medical Sciences, Department of Paediatric Orthopaedics, Poznan (Poland); Ignys-O' Byrne, Anna [J. Strus City Hospital, Department of Radiology, Poznan (Poland); Ignys, Iwona [Karol Marcinkowski University of Medical Sciences, Department of Paediatric Gastroenterology and Metabolic Diseases, Poznan (Poland); Wroblewska, Katarzyna [Karol Marcinkowski University of Medical Sciences, Department of Radiology, Poznan (Poland)

    2011-02-15

    The aim of this paper is to evaluate the frequency of limb shortening in the course of solitary bone cyst treatment. The correlation between the mode of treatment as well as the occurrence of pathological fracture, cyst location, volume, and locularity were examined. A retrospective analysis was carried out on 135 patients where 80 underwent curettage and bone grafting and 55 were administered methylprednisolone injection with a mean time to follow-up of 12 years. Based on clinical and radiological evaluation, limb shortening was found in ten patients when the data before and after treatment was compared. Limb shortening ranging from 1 to 5 cm during the course of the treatment was observed: six in humerus, two in femur, two in tibia. Those with epiphyseal changes, magnetic resonance imaging to evaluate the degree of growth plate damage was performed. Patients with and without limb shortening did not differ statistically regarding the applied method of treatment. The cyst volume was significantly larger in the group of patients with limb shortening when compared to the group of patients with no limb shortening. In patients treated with curettage and bone grafting, the mode of treatment does not increase the frequency of occurrence of iatrogenic limb shortening. In patients with limb shortening, a statistically significant larger volume of the cyst was observed. (orig.)

  19. Assisting High School Students with Career Indecision Using a Shortened Form of the Career Construction Interview

    Science.gov (United States)

    Rehfuss, Mark C.; Sickinger, Pamela H.

    2015-01-01

    A shortened form of the Career Construction Interview (CCI) was used to help high school students struggling with the career decision making process. The shortened instrument is described, as well as, its use with eleventh grade high school students who had low levels of career concern and career curiosity. Students who completed the exercise…

  20. Accommodation of collisional shortening along the Alpine plate boundary : plate kinematics vs rheological controls

    Science.gov (United States)

    Rosenberg, Claudio; Bellahsen, Nicolas

    2016-04-01

    The style of collision in the Alps varies along strike, reflecting different amounts and different modes of accommodation of collisional shortening. These differences control the patterns of exhumation during collision. Whereas the western Alps largely consist of a metamorphic complex formed during subduction and largely exhumed before the initiation of collision, the subduction nappe-stack of the Central and the Eastern Alps is strongly overprinted by collisional shortening and by Barrovian metamorphism. Based on compiled and new data we estimate amounts of collisional shortening along the strike of the chain and set it in relationship to the geometry of the collisional prism. The western Alpine collisional structures form a very large (in map view), but moderately shortened wedge, terminating in front of a poorly developed Molasse basin. Shortening of this wedge was mainly localized along its external parts, resulting in accretion of basement and cover units thrusted towards the foreland. Back-folding and back-thrusting are barely developed and no shortening takes place in the upper, Adriatic plate. In the Central Alps, the amount of collisional shortening is larger and it is distributed both in the lower and in the upper plate. The collisional prism is bivergent and partitioning of the amount of shortening between the upper and lower plates varies along strike, being most probably controlled by rheological, heterogeneities. The thickened accreted lower plate is strongly affected by Barrovian metamorphism where shortening is largest and localized within a confined area. A deep Molasse basin developed in front of the prism. In the Eastern Alps collisional kinematics vary from east to west, with orogen-parallel displacements dominating in the east and orogen-perpendicular ones in the West, where they culminate in the structural and metamorphic dome of the Tauern Window. Nowhere else in the Alps collisional shortening is so strongly localized in one and the same

  1. Evaluation of canola oil oleogels with candelilla wax as an alternative to shortening in baked goods.

    Science.gov (United States)

    Jang, Areum; Bae, Woosung; Hwang, Hong-Sik; Lee, Hyeon Gyu; Lee, Suyong

    2015-11-15

    The oleogels of canola oil with candelilla wax were prepared and utilized as a shortening replacer to produce cookies with a high level of unsaturated fatty acids. The incorporation of candelilla wax (3% and 6% by weight) to canola oil produced the oleogels with solid-like properties. The firmness of the oleogels was lower than that of the shortening at room temperature. A more rapid change in the viscosity with temperature was observed with increasing levels of candelilla wax in the steady shear measurements. The replacement of shortening with oleogels in the cookie formulation reduced both viscoelastic parameters (G' and G") of the cookie doughs. The level of unsaturated fatty acids in the oleogel cookies was distinctly increased up to around 92%, compared to the shortening cookies (47.2%). The cookies with the oleogels showed desirable spreadable property and the replacement of shortening with the oleogels produced cookies with soft eating characteristics.

  2. Shortening treatment time in robotic radiosurgery using a novel node reduction technique

    Energy Technology Data Exchange (ETDEWEB)

    Water, Steven van de; Hoogeman, Mischa S.; Breedveld, Sebastiaan; Heijmen, Ben J. M. [Department of Radiation Oncology, Erasmus MC-Daniel den Hoed Cancer Center, Groene Hilledijk 301, 3075 EA Rotterdam (Netherlands)

    2011-03-15

    Purpose: The fraction duration of robotic radiosurgery treatments can be reduced by generating more time-efficient treatment plans with a reduced number of node positions, beams, and monitor units (MUs). Node positions are preprogramed locations where the robot can position the focal spot of the x-ray beam. As the time needed for the robot to travel between node positions takes up a large part of the treatment time, the aim of this study was to develop and evaluate a node reduction technique in order to reduce the treatment time per fraction for robotic radiosurgery. Methods: Node reduction was integrated into the inverse planning algorithm, developed in-house for the robotic radiosurgery modality. It involved repeated inverse optimization, each iteration excluding low-contribution node positions from the planning and resampling new candidate beams from the remaining node positions. Node reduction was performed until the exclusion of a single node position caused a constraint violation, after which the shortest treatment plan was selected retrospectively. Treatment plans were generated with and without node reduction for two lung cases of different complexity, one oropharyngeal case and one prostate case. Plan quality was assessed using the number of node positions, beams and MUs, and the estimated treatment time per fraction. All treatment plans had to fulfill all clinical dose constraints. Extra constraints were added to maintain the low-dose conformality and restrict skin doses during node reduction. Results: Node reduction resulted in 12 residual node positions, on average (reduction by 77%), at the cost of an increase in the number of beams and total MUs of 28% and 9%, respectively. Overall fraction durations (excluding patient setup) were shortened by 25% (range of 18%-40%), on average. Dose distributions changed only little and dose in low-dose regions was effectively restricted by the additional constraints. Conclusions: The fraction duration of robotic

  3. Chronic food restriction in young rats results in depression- and anxiety-like behaviors with decreased expression of serotonin reuptake transporter.

    Science.gov (United States)

    Jahng, Jeong Won; Kim, Jae Goo; Kim, Hyoung Jin; Kim, Bom-Taeck; Kang, Dong-Won; Lee, Jong-Ho

    2007-05-30

    Evidence of semi-starvation is commonly found in patients with eating disorders. This study was conducted to examine the adverse effects of chronic caloric restriction in young rats, since there have been increasing incidence of eating disorders especially among young populations. Food restriction group was supplied daily with 50% of chow consumed by its ad libitum fed control group from postnatal day 28. After 5 weeks of food restriction, brain contents of serotonin (5-hydroxy-tryptamine; 5-HT) and its metabolite 5-hydroxyindol acetic acid were analyzed by high-performance liquid chromatography and mRNA expression of 5-HT reuptake transporter (5-HTT) by in situ hybridization. Plasma corticosterone levels were determined by radioimmunoassay. Behavioral assessments were performed with Porsolt swim test for depressive behavior and with elevated plus maze test for anxiety. Five weeks of food restriction markedly increased plasma level of corticosterone, and significantly decreased 5-HT turnover rates in the hippocampus and the hypothalamus. 5-HTT mRNA expression decreased in the raphe nucleus of food restricted rats compared with free fed controls. Immobility time during the swim test increased in the food restricted group, compared to the control group. Food restricted rats spent more time in the closed arms, less time in the open arms, of elevated plus maze compared with control rats. These results suggest that chronic caloric restriction in young rats may lead to the development of depressive and/or anxiety disorders, likely, in relation with dysfunction of brain 5-HT system.

  4. Líneas de calor para convección natural en cavidades cerradas: Tres casos de estudio

    OpenAIRE

    J.G. Cervantes de Gortari; J.C. Torchia-Núñez; J.A. Serrano-Gutiérrez; A. Muñoz-Barrera; E. Guzmán-Vázquez; F. Gutiérrez-Coria; O. Chávez-López; I. Rosas-Yescas; E. Martínez-Galván

    2010-01-01

    Se presenta la técnica de visualización de líneas de calor para tres casos específicos de convección natural en cavidades cerradas. El objetivo es mostrar las ventajas de visualizar la transferencia de calor para un fluido en movimiento en lugar del uso de isotermas. Los tres casos de estudio se tomaron arbitraria mente por ser casos estudiados experimental y numéricamente, donde se conocen los campos de velocidad y temperatura, también por ser casos donde el régimen de trasferencia de calor ...

  5. Automobilismo: no calor da competição Automovilismo: en el calor de la competición Car racing: in the heat of competition

    Directory of Open Access Journals (Sweden)

    Luiz Oswaldo Carneiro Rodrigues

    2004-06-01

    Full Text Available O presente artigo questiona o papel do calor como um fator de risco adicional para o acidente que vitimou Ayrton Senna. O automobilismo de competição constitui um desafio biológico, uma situação estressante do ponto de vista mental e físico. A manutenção da performance depende da disponibilidade de carboidratos e oxigênio, hidratação adequada e temperatura interna constante entre 37 e 38 graus centígrados. A dissipação do calor produzido pelo metabolismo ocorre através do aumento do fluxo de sangue para pele e produção de suor e manter a temperatura cerebral constante se constitui num problema permanente. Verificou-se experimentalmente que a energia necessária para dirigir um automóvel de corrida é comparável a um esporte como o voleibol. Durante uma corrida, o indivíduo está exposto a um microambiente quente na cabina, que pode atingir 50ºC, gerado por fontes de calor mecânicas e ambientais. O bloqueio da evaporação do suor pelo macacão resulta em umidade e desconforto pessoal, o que implica maior esforço mental para dirigir o carro. As medidas contra o calor começam antes da corrida, cuidando-se do estado nutricional, da hidratação e principalmente do condicionamento físico através de exercícios aeróbios regulares e adequados, que permitem aumentar a capacidade de trabalho e a tolerância ao calor, o que resulta em menor fadiga durante a corrida. Outro procedimento importante deveria ser a aclimatação prévia dos pilotos aos ambientes quentes e úmidos. Deve-se fazer o possível para reduzir o aquecimento do veículo e respeitar o sistema de bandeiras de advertência para os riscos de hipertermia. Em conclusão, embora Ayrton Senna fosse um indivíduo com maior risco de desenvolver hipertermia, independentemente de outras causas, não parece ter havido tempo de corrida suficiente para haver produção de calor metabólico capaz de aumentar excessivamente a temperatura interna do piloto nas condi

  6. Coeficientes de transferencia de calor y pérdida de eficiencia en intercambiadores de calor de placas durante el enfriamiento del licor amoniacal

    Directory of Open Access Journals (Sweden)

    Enrique Torres-Tamayo

    2011-10-01

    Full Text Available En la planta de Recuperación de Amoniaco de la empresa niquelera Ernesto Che Guevara la pérdida de eficiencia del proceso de enfriamiento del licor amoniacal, mediante el uso de intercambiadores de calor de placas, se asocia a la incorrecta estimación de los coeficientes de transferencia de calor y la acumulación de incrustaciones en la superficie de intercambio; lo anterior incrementa el consumo de agua, la energía disponible en el sistema y los costos de mantenimiento. Se realizó una investigación en un intercambiador de calor de placas, con el objetivo de determinar los coeficientes de transferencia y la influencia de las incrustaciones en la pérdida de eficiencia de la instalación. Mediante un procedimiento iterativo se determinó la ecuación del número de Nusselt y su dependencia con el Reynolds y Prandtl, para ello se utilizó un diseño experimental multifactorial y mediciones de los parámetros de trabajo de la instalación en función del tiempo. Los resultados predicen el conocimiento de los coeficientes para el cálculo del número de Nusselt, con los valores de Reynolds y Prandtl, para ambos fluidos (licor amoniacal y agua. Los valores de los coeficientes del licor son inferiores, ello se debe a la presencia de componentes gaseosos. La comparación con resultados de otros autores muestra correspondencia con los de Thonon. Se recomienda la limpieza y mantenimiento de la instalación en un período de 27 días debido a la reducción de la eficiencia térmica hasta valores inferiores al 70 %.

  7. Blood glucose regulation during fasting in rats under food restriction since birth

    Directory of Open Access Journals (Sweden)

    Adriana de Souza Vitoriano

    2011-02-01

    Full Text Available The effect of severe food restriction since birth on regulation of fasting glycemia in male Wistar rats was investigated. The control group (CG had free supply of chow, while the restriction group (RG received 50% of the amount ingested by the CG. The experiments were done in adult (60 days overnight fasted rats in which glycemia, liver free glucose levels and hepatic glycogen concentration were measured. In part of the experiments in situ liver perfusion was done. The results showed that livers from the RG had higher glycogenolysis rates but lower gluconeogenesis rates from L-alanine (10 mM. Since RG showed maintained glycemia during fasting, it could be concluded that livers from RG produced glucose preferentially from glycogenolysis in detriment of gluconeogenesis. These findings demonstrated that in spite of severe caloric restriction, the metabolic adaptations of the liver did exist to assure the maintenance of blood glucose for brain supply during fasting.

  8. Research on heat pumps in Mexico operating with geothermal energy and waste heat; Investigacion sobre bombas de calor en Mexico operando con energia geotermica y calor de desecho

    Energy Technology Data Exchange (ETDEWEB)

    Garcia-Gutierrez, A; Barragan-Reyes, R.M; Arellano-Gomez, V [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: aggarcia@iie.org.mx

    2008-01-15

    The Instituto de Investigaciones Electricas and the Comision Federal de Electricidad have done research and development (R&D) on heat pumps (HP) in past years. Tested systems include mechanical compression, absorption and heat-transformers. The main R&D aspects on HP are briefly described, and also a more detailed description about three of the main studies is presented: (a) a mechanical compression HP of the water-water type operated with low-pressure geothermal steam at the Los Azufres; Mich., geothermal field, and designed for purification of brine; (b) an absorption HP for cooling and refrigeration operating with ammonia-water and low-enthalpy geothermal energy, which was tested in the Los Azufres and Cerro Prieto, BC, geothermal fields; and (c) a heat-transformer by absorption-Absorption Heat Pump Type II-tested to assess the performance of several ternary solutions as work fluids. Plans exist to install and test a geothermal heat pump at Cerro Prieto or Mexicali, BC. [Spanish] El Instituto de Investigaciones Electricas y la Comision Federal de Electricidad han realizado trabajo de investigacion y desarrollo (I&D) sobre bombas de calor (BC) en el pasado. Los sistemas probados incluyen compresion mecanica, absorcion y transformadores termicos. Este trabajo describe brevemente los principales aspectos de I&D sobre bombas de calor en forma general, y se da una descripcion mas detallada de tres de los principales estudios: (a) una BC por compresion mecanica tipo agua-agua disenada para purificacion de salmueras operando con vapor geotermico de baja presion en el campo geotermico de Los Azufres, Mich.; (b) una BC por absorcion para enfriamiento y refrigeracion operando con amoniaco-agua y energia geotermica de baja entalpia, la cual fue probada en los campos geotermicos de Los Azufres y Cerro Prieto, BC; y (c) un transformador termico por absorcion -llamado Bomba de Calor por Absorcion Tipo II--, el cual fue probado para evaluar el comportamiento de diversas

  9. Food restriction and refeeding induces changes in lipid pathways and fat deposition in the adipose and hepatic tissues in rats with diet-induced obesity.

    Science.gov (United States)

    Duarte, Fernanda Oliveira; Sene-Fiorese, Marcela; Cheik, Nadia Carla; Maria, Adriana Simone Lopes Santa; de Aquino, Antônio Eduardo; Oishi, Jorge Camargo; Rossi, Elizeu Antônio; Garcia de Oliveira Duarte, Ana Cláudia; Dâmaso, Ana Raimunda

    2012-07-01

    The aim of this study was to determine the effects of successive cycles of a moderately restrictive diet and refeeding with a high-fat diet on the metabolism of the adipose and hepatic tissues of obese rats. Rats were assigned to the following groups: a chow diet; a high-fat diet; a moderate caloric restriction; or a moderate caloric restriction plus refeeding. Some animals in each group were given [1-(14)C]triolein intragastrically, while others received an intraperitoneal injection of 3 mCi (3)H(2)O. All animals were killed by decapitation. The retroperitoneal, visceral epididymal and omental white adipose tissues, brown adipose tissue, liver and blood were immediately removed. The lipid uptake from the diet, in vivo rate of lipogenesis, percentage of fat, lipid profile and leptin concentration were analysed. The high-fat diet promoted an increase in fatty liver (P ≤ 0.05), adiposity mass (P ≤ 0.05) and the plasma concentration of leptin (P ≤ 0.05) and a decreased lipid uptake in white adipose tissue depots (P ≤ 0.05) in relation to the chow diet. The moderate caloric restriction did not reverse the changes promoted by the high-fat diet but induced a small decrease in adiposity, which was reversed after refeeding, and the animals maintained a dyslipidaemic profile and high fat deposition in the liver. We can conclude that the high-fat diet and subsequent moderate caloric restriction plus refeeding increased the risks of developing visceral obesity, dyslipidaemia and non-alcoholic fatty liver disease, which suggests that this type of experimental protocol can be used to study mechanisms related to the metabolic syndrome.

  10. The low-methionine content of vegan diets may make methionine restriction feasible as a life extension strategy.

    Science.gov (United States)

    McCarty, Mark F; Barroso-Aranda, Jorge; Contreras, Francisco

    2009-02-01

    Recent studies confirm that dietary methionine restriction increases both mean and maximal lifespan in rats and mice, achieving "aging retardant" effects very similar to those of caloric restriction, including a suppression of mitochondrial superoxide generation. Although voluntary caloric restriction is never likely to gain much popularity as a pro-longevity strategy for humans, it may be more feasible to achieve moderate methionine restriction, in light of the fact that vegan diets tend to be relatively low in this amino acid. Plant proteins - especially those derived from legumes or nuts - tend to be lower in methionine than animal proteins. Furthermore, the total protein content of vegan diets, as a function of calorie content, tends to be lower than that of omnivore diets, and plant protein has somewhat lower bioavailability than animal protein. Whole-food vegan diets that moderate bean and soy intake, while including ample amounts of fruit and wine or beer, can be quite low in methionine, while supplying abundant nutrition for health (assuming concurrent B12 supplementation). Furthermore, low-fat vegan diets, coupled with exercise training, can be expected to promote longevity by decreasing systemic levels of insulin and free IGF-I; the latter effect would be amplified by methionine restriction - though it is not clear whether IGF-I down-regulation is the sole basis for the impact of low-methionine diets on longevity in rodents.

  11. Late gestational nutrient restriction

    DEFF Research Database (Denmark)

    Tygesen, Malin Plumhoff; Nielsen, Mette Olaf; Nørgaard, Peder;

    2008-01-01

    We investigated the effect of 50% nutrient restriction during the last 6 weeks of gestation on twin-pregnant ewes' plasma glucose, non-esterified fatty acid, ß-hydroxybutyrate, insulin, IGF-1 and leptin concentrations and the effects on lamb birth weight and ewes' lactation performance. Plasma...... metabolite and hormone concentrations in restricted ewes suggest that maternal tissues were being mobilised. Despite the ewes' adaptations their lambs weighed significantly less at birth. Furthermore, colostrum and milk yields were markedly reduced up until the latest measurement at 3 weeks post partum...

  12. Effects of muscle fibre shortening on the characteristics of surface motor unit potentials.

    Science.gov (United States)

    Rodriguez-Falces, Javier; Place, Nicolas

    2014-02-01

    Traditionally, studies dealing with muscle shortening have concentrated on assessing its impact on conduction velocity, and to this end, electrodes have been located between the end-plate and tendon regions. Possible morphologic changes in surface motor unit potentials (MUPs) as a result of muscle shortening have not, as yet, been evaluated or characterized. Using a convolutional MUP model, we investigated the effects of muscle shortening on the shape, amplitude, and duration characteristics of MUPs for different electrode positions relative to the fibre-tendon junction and for different depths of the MU in the muscle (MU-to-electrode distance). It was found that the effects of muscle shortening on MUP morphology depended not only on whether the electrodes were between the end-plate and the tendon junction or beyond the tendon junction, but also on the specific distance to this junction. When the electrodes lie between the end-plate and tendon junction, it was found that (1) the muscle shortening effect is not important for superficial MUs, (2) the sensitivity of MUP amplitude to muscle shortening increases with MU-to-electrode distance, and (3) the amplitude of the MUP negative phase is not affected by muscle shortening. This study provides a basis for the interpretation of the changes in MUP characteristics in experiments where both physiological and geometrical aspects of the muscle are varied.

  13. Multiple causes of fatigue during shortening contractions in rat slow twitch skeletal muscle.

    Science.gov (United States)

    Hortemo, Kristin Halvorsen; Munkvik, Morten; Lunde, Per Kristian; Sejersted, Ole M

    2013-01-01

    Fatigue in muscles that shorten might have other causes than fatigue during isometric contractions, since both cross-bridge cycling and energy demand are different in the two exercise modes. While isometric contractions are extensively studied, the causes of fatigue in shortening contractions are poorly mapped. Here, we investigate fatigue mechanisms during shortening contractions in slow twitch skeletal muscle in near physiological conditions. Fatigue was induced in rat soleus muscles with maintained blood supply by in situ shortening contractions at 37°C. Muscles were stimulated repeatedly (1 s on/off at 30 Hz) for 15 min against a constant load, allowing the muscle to shorten and perform work. Fatigue and subsequent recovery was examined at 20 s, 100 s and 15 min exercise. The effects of prior exercise were investigated in a second exercise bout. Fatigue developed in three distinct phases. During the first 20 s the regulatory protein Myosin Light Chain-2 (slow isoform, MLC-2s) was rapidly dephosphorylated in parallel with reduced rate of force development and reduced shortening. In the second phase there was degradation of high-energy phosphates and accumulation of lactate, and these changes were related to slowing of muscle relengthening and relaxation, culminating at 100 s exercise. Slowing of relaxation was also associated with increased leak of calcium from the SR. During the third phase of exercise there was restoration of high-energy phosphates and elimination of lactate, and the slowing of relaxation disappeared, whereas dephosphorylation of MLC-2s and reduced shortening prevailed. Prior exercise improved relaxation parameters in a subsequent exercise bout, and we propose that this effect is a result of less accumulation of lactate due to more rapid onset of oxidative metabolism. The correlation between dephosphorylation of MLC-2s and reduced shortening was confirmed in various experimental settings, and we suggest MLC-2s as an important regulator of

  14. Multiple causes of fatigue during shortening contractions in rat slow twitch skeletal muscle.

    Directory of Open Access Journals (Sweden)

    Kristin Halvorsen Hortemo

    Full Text Available Fatigue in muscles that shorten might have other causes than fatigue during isometric contractions, since both cross-bridge cycling and energy demand are different in the two exercise modes. While isometric contractions are extensively studied, the causes of fatigue in shortening contractions are poorly mapped. Here, we investigate fatigue mechanisms during shortening contractions in slow twitch skeletal muscle in near physiological conditions. Fatigue was induced in rat soleus muscles with maintained blood supply by in situ shortening contractions at 37°C. Muscles were stimulated repeatedly (1 s on/off at 30 Hz for 15 min against a constant load, allowing the muscle to shorten and perform work. Fatigue and subsequent recovery was examined at 20 s, 100 s and 15 min exercise. The effects of prior exercise were investigated in a second exercise bout. Fatigue developed in three distinct phases. During the first 20 s the regulatory protein Myosin Light Chain-2 (slow isoform, MLC-2s was rapidly dephosphorylated in parallel with reduced rate of force development and reduced shortening. In the second phase there was degradation of high-energy phosphates and accumulation of lactate, and these changes were related to slowing of muscle relengthening and relaxation, culminating at 100 s exercise. Slowing of relaxation was also associated with increased leak of calcium from the SR. During the third phase of exercise there was restoration of high-energy phosphates and elimination of lactate, and the slowing of relaxation disappeared, whereas dephosphorylation of MLC-2s and reduced shortening prevailed. Prior exercise improved relaxation parameters in a subsequent exercise bout, and we propose that this effect is a result of less accumulation of lactate due to more rapid onset of oxidative metabolism. The correlation between dephosphorylation of MLC-2s and reduced shortening was confirmed in various experimental settings, and we suggest MLC-2s as an

  15. Non-caloric artificial sweeteners and the microbiome: findings and challenges.

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health.

  16. Non-caloric artificial sweeteners and the microbiome: findings and challenges

    Science.gov (United States)

    Suez, Jotham; Korem, Tal; Zilberman-Schapira, Gili; Segal, Eran; Elinav, Eran

    2015-01-01

    Non-caloric artificial sweeteners (NAS) are common food supplements consumed by millions worldwide as means of combating weight gain and diabetes, by retaining sweet taste without increasing caloric intake. While they are considered safe, there is increasing controversy regarding their potential ability to promote metabolic derangements in some humans. We recently demonstrated that NAS consumption could induce glucose intolerance in mice and distinct human subsets, by functionally altering the gut microbiome. In this commentary, we discuss these findings in the context of previous and recent works demonstrating the effects of NAS on host health and the microbiome, and the challenges and open questions that need to be addressed in understanding the effects of NAS consumption on human health. PMID:25831243

  17. Caloric curve of 8 GeV/c negative pion and antiproton + Au reactions

    CERN Document Server

    Ruangma, A; Martin, E; Ramakrishnan, E; Rowland, D J; Veselsky, M; Winchester, E M; Yennello, S J; Beaulieu, L; Hsi, W C; Kwiatkowski, K K; Lefort, T; Viola, V E; Botvina, A; Korteling, R G; Pienkowski, L; Breuer, H; Gushue, S; Remsberg, L P

    2002-01-01

    The relationship between nuclear temperature and excitation energy of hot nuclei formed by 8 GeV/c negative pion and antiproton beams incident on 197Au has been investigated with the ISiS 4-pidetector array at the BNL AGS accelerator. The double-isotope-ratio technique was used to calculate the temperature of the hot system. The two thermometers used (p/d-3He/4He) and (d/t-3He/4He) are in agreement below E*/A ~ 7 MeV when corrected for secondary decay. Comparison of these caloric curves to those from other experiments shows some differences that may be attributable to instrumentation and analysis procedures. The caloric curves from this experiment are also compared with the predictions from the SMM multifragmentation model.

  18. Equipos de transferencia de calor: una guía de estudio

    OpenAIRE

    Carrero Mantilla, Javier Ignacio

    2008-01-01

    La transferencia de calor es una ciencia básica de la ingeniería, que se incluye en los planes de estudio en muchas de las ramas de la profesión: mecánica, química, de alimentos, entre otras. En general, es posible dividir el estudio de la transferencia de calor en dos partes: la primera comprende los principios básicos del transporte de energía y de materia, mientras que la segunda se dedica al diseño y a la evaluación de equipos. El libro está distribuido en seis capítulos y dos apéndice...

  19. Mechanism‐Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    Science.gov (United States)

    Sonne, DP; Hansen, M; Bagger, JI; Lund, A; Rehfeld, JF; Alskär, O; Karlsson, MO; Vilsbøll, T; Knop, FK; Bergstrand, M

    2016-01-01

    Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism‐based model for GE, cholecystokinin plasma concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may potentially be used to predict postprandial changes in drug absorption. PMID:28028939

  20. (Magneto)caloric refrigeration: is there light at the end of the tunnel?

    Science.gov (United States)

    Pecharsky, Vitalij K; Cui, Jun; Johnson, Duane D

    2016-08-13

    Caloric cooling and heat pumping rely on reversible thermal effects triggered in solids by magnetic, electric or stress fields. In the recent past, there have been several successful demonstrations of using first-order phase transition materials in laboratory cooling devices based on both the giant magnetocaloric and elastocaloric effects. All such materials exhibit non-equilibrium behaviours when driven through phase transformations by corresponding fields. Common wisdom is that non-equilibrium states should be avoided; yet, as we show using a model material exhibiting a giant magnetocaloric effect, non-equilibrium phase-separated states offer a unique opportunity to achieve uncommonly large caloric effects by very small perturbations of the driving field(s).This article is part of the themed issue 'Taking the temperature of phase transitions in cool materials'.

  1. Mechanism-Based Modeling of Gastric Emptying Rate and Gallbladder Emptying in Response to Caloric Intake

    DEFF Research Database (Denmark)

    Guiastrennec, B; Sonne, D P; Hansen, M;

    2016-01-01

    concentrations were not predictive of GBE, and an alternative model linking the nutrients amount in the upper intestine to GBE was preferred. Relative to fats, the potency on GBE was 68% for proteins and 2.3% for carbohydrates. The model predictions were robust across a broad range of nutritional content and may......Bile acids released postprandially modify the rate and extent of absorption of lipophilic compounds. The present study aimed to predict gastric emptying (GE) rate and gallbladder emptying (GBE) patterns in response to caloric intake. A mechanism-based model for GE, cholecystokinin plasma...... concentrations, and GBE was developed on data from 33 patients with type 2 diabetes and 33 matched nondiabetic individuals who were administered various test drinks. A feedback action of the caloric content entering the proximal small intestine was identified for the rate of GE. The cholecystokinin...

  2. Desarrollos instrumentales en microcalorimetría de conducción de calor

    Directory of Open Access Journals (Sweden)

    Liliana Girlado G.

    2010-07-01

    Full Text Available Se presentan aspectos generales de la microcalorimetría de conducción de calor. Se describe el diseño y la operación de microcalorímetros de conducción de calor estático y de flujo construidos en este laboratorio, los cuales fueron calibrados eléctrica y químicamente. Estos equipos se emplean en la caracterización de sólidos porosos por la técnica de calorimetría de inmersión y en la determinación de entalpias de transferencia de solutos; su uso se ilustra con algunos resultados típicos. Se mencionan además otras aplicaciones que se dan actualmente a estos aparatos.

  3. Parental attachment insecurity predicts child and adult high-caloric food consumption.

    Science.gov (United States)

    Faber, Aida; Dubé, Laurette

    2015-05-01

    Eating habits are established early and are difficult to change once formed. This study investigated the role of caregiver-child attachment quality and its associations with high-caloric food consumption in a sample of middle socio-economic status children and adults, respectively. Survey data were collected from an online questionnaire administered separately to 213 (143 girls) children and 216 parents (adult sample; 180 women). Two studies showed that an insecure parental attachment, whether actual (Study 1; children) or recalled (Study 2; adults), significantly and positively predicted high-caloric food consumption in both samples. The present findings highlight the importance of parental attachment and its association with unhealthy eating patterns in children and adults.

  4. Calorie restriction and stroke

    Directory of Open Access Journals (Sweden)

    Manzanero Silvia

    2011-09-01

    Full Text Available Abstract Stroke, a major cause of disability and mortality in the elderly, occurs when a cerebral blood vessel is occluded or ruptured, resulting in ischemic damage and death of brain cells. The injury mechanism involves metabolic and oxidative stress, excitotoxicity, apoptosis and inflammatory processes, including activation of glial cells and infiltration of leukocytes. In animal models, dietary energy restriction, by daily calorie reduction (CR or intermittent fasting (IF, extends lifespan and decreases the development of age-related diseases. Dietary energy restriction may also benefit neurons, as suggested by experimental evidence showing that CR and IF protect neurons against degeneration in animal models. Recent findings by our group and others suggest the possibility that dietary energy restriction may protect against stroke induced brain injury, in part by inducing the expression of neurotrophic factors, such as brain-derived neurotrophic factor (BDNF and basic fibroblast growth factor (bFGF; protein chaperones, including heat shock protein 70 (Hsp70 and glucose regulated protein 78 (GRP78; antioxidant enzymes, such as superoxide dismutases (SOD and heme oxygenase-1 (HO-1, silent information regulator T1 (SIRT1, uncoupling proteins and anti-inflammatory cytokines. This article discusses the protective mechanisms activated by dietary energy restriction in ischemic stroke.

  5. Training Restricted Boltzmann Machines

    DEFF Research Database (Denmark)

    Fischer, Asja

    Restricted Boltzmann machines (RBMs) are probabilistic graphical models that can also be interpreted as stochastic neural networks. Training RBMs is known to be challenging. Computing the likelihood of the model parameters or its gradient is in general computationally intensive. Thus, training...

  6. Bilinear Fourier restriction theorems

    CERN Document Server

    Demeter, Ciprian

    2012-01-01

    We provide a general scheme for proving $L^p$ estimates for certain bilinear Fourier restrictions outside the locally $L^2$ setting. As an application, we show how such estimates follow for the lacunary polygon. In contrast with prior approaches, our argument avoids any use of the Rubio de Francia Littlewood--Paley inequality.

  7. DISEÑO Y CONSTRUCCIÓN DE PROTOTIPO PARA MEDICIÓN DE FLUJO DE CALOR APLICANDO CALORIMETRÍA DIRECTA: SENSADO POR FLUJO DE CALOR

    Directory of Open Access Journals (Sweden)

    OSCAR CADENA

    2008-01-01

    Full Text Available El presente artículo describe el diseño de un prototipo inalámbrico para la medición de flujo de calor, que permita a futuro aplicar el método de calorimetría directa por gradiente de flujo de calor en el área de la electrónica médica. Esta técnica se desarrolla gracias al avance y creación de sensores que permiten medir este tipo de variables, y se postula como una alternativa a las formas de medición utilizadas actualmente, presentando mejoras en su desempeño y costo. Los resultados obtenidos luego de efectuar la calibración del equipo permiten inferir que la técnica propuesta se adapta de forma eficiente y puede utilizarse como un sustituto significativamente más ventajoso comparado con los métodos existentes en la actualidad y aplicados en el seguimiento metabólico de personas.

  8. Temas de Física para Ingeniería: Temperatura y propagación del calor

    OpenAIRE

    Beléndez Vázquez, Augusto

    1992-01-01

    Acústica, fluidos y termodinámica: "Temperatura y propagación del calor". Introducción. Descripciones macroscópica y microscópica de un sistema. Equilibrio térmico y principio cero de la termodinámica. Termómetros y escala de temperaturas del gas ideal. Dilatación térmica. Propagación del calor.

  9. Caloric Vestibular Stimulation as a Treatment for Conversion Disorder: A Case Report and Medical Hypothesis

    OpenAIRE

    Michael eNoll-Hussong; Sabrina eHolzapfel; Dan ePokorny; Simone D Herberger

    2014-01-01

    Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS) has been demonstrated to modulate transiently a variety of cognitive ...

  10. Heat pump for purification of geothermal brines; Bomba de calor para purificacion de salmuera geotermica

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo-Gutierrez, S; Barragan-Reyes, R.M; Holland, F.A [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)]. E-mail: rmb@iie.org.mx

    2007-01-15

    Integrated use of geothermal resources is one of the most important goals for the future. Presently geothermal heat pumps offer two benefits: using heat from residual brines and converting these brines into very pure water. Designs and descriptions are presented of an experimental system to purify geothermal brines integrated to an adsorption heat-pump. The system was constructed and tested in the IIE (Institute for Electrical Research) facilities. During the experimental stage, pure water was obtained. Maximum capacity for pure water was 4.3 kg per hour, presenting an Actual Coefficient of Performance (COP)A of 1.4. The results are encouraging to project units at an industrial level for operating with geothermal and/or solar heat. [Spanish] El aprovechamiento integral de los recursos geotermicos en todas sus formas es una de las metas importantes a lograr en los proximos anos. Hoy en dia, el uso de las bombas de calor en la geotermia ofrece un doble beneficio: aprovechan el calor de los fluidos de desecho y tienen la capacidad de transformar la salmuera geotermica en agua de alta pureza. Se presenta el diseno y descripcion de un sistema experimental para purificacion de salmuera geotermica integrado a una bomba de calor por absorcion, el cual fue construido y probado en el Instituto de Investigaciones Electricas. En toda la etapa de experimentacion se obtuvo agua pura. La capacidad maxima alcanzada de produccion de agua pura de este sistema fue de 4.3 kg por hora, mostrando un rendimiento en terminos del Coeficiente Real de Rendimiento (COP)A de 1.4. Estos resultados se consideran alentadores para la proyeccion de unidades a escala industrial que puedan ser operadas con calor geotermico y/o solar.

  11. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    OpenAIRE

    Gabriel Eduardo Rocha Camino; Rangel Jara, Hermes A.

    2011-01-01

    En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  12. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests.

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  13. Vestibular function tests for vestibular migraine: clinical implication of video head impulse and caloric tests

    Directory of Open Access Journals (Sweden)

    Woo Seok Kang

    2016-09-01

    Full Text Available Vestibular migraine (VM is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT, caloric test, vestibular-evoked myogenic potentials (VEMP, and sensory organization test (SOT at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR was defined as no need for continued medication, partial response (PR as improved symptoms but need for continued medication, and no response (NR as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11% exhibited abnormal vHIT results, 14 of 73 (19% exhibited abnormal caloric test results, 25 of 65 (38% exhibited abnormal SOT results, 8 of 75 (11% exhibited abnormal cervical VEMP results, and 20 of 75 (27% exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78% no longer required medication (CR, while 18 (22% still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively. Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  14. Vestibular Function Tests for Vestibular Migraine: Clinical Implication of Video Head Impulse and Caloric Tests

    Science.gov (United States)

    Kang, Woo Seok; Lee, Sang Hun; Yang, Chan Joo; Ahn, Joong Ho; Chung, Jong Woo; Park, Hong Ju

    2016-01-01

    Vestibular migraine (VM) is one of the most common causes of episodic vertigo. We reviewed the results of multiple vestibular function tests in a cohort of VM patients who were diagnosed with VM according to the diagnostic criteria of the Barany Society and the International Headache Society and assessed the efficacy of each for predicting the prognosis in VM patients. A retrospective chart analysis was performed on 81 VM patients at a tertiary care center from June 2014 to July 2015. Patients were assessed by the video head impulse test (vHIT), caloric test, vestibular-evoked myogenic potentials (VEMPs), and sensory organization test (SOT) at the initial visit and then evaluated for symptomatic improvement after 6 months. Complete response (CR) was defined as no need for continued medication, partial response (PR) as improved symptoms but need for continued medication, and no response (NR) as no symptomatic improvement and requiring increased dosage or change in medications. At the initial evaluation, 9 of 81 patients (11%) exhibited abnormal vHIT results, 14 of 73 (19%) exhibited abnormal caloric test results, 25 of 65 (38%) exhibited abnormal SOT results, 8 of 75 (11%) exhibited abnormal cervical VEMP results, and 20 of 75 (27%) exhibited abnormal ocular VEMP results. Six months later, 63 of 81 patients (78%) no longer required medication (CR), while 18 (22%) still required medication, including 7 PR and 11 NR patients. Abnormal vHIT gain and abnormal caloric results were significantly related to the necessity for continued medication at 6-month follow-up (OR = 5.67 and 4.36, respectively). Abnormal vHIT and caloric test results revealed semicircular canal dysfunction in VM patients and predicted prolonged preventive medication requirement. These results suggest that peripheral vestibular abnormalities are closely related to the development of vertigo in VM patients.

  15. Effects of caloric deprivation and satiety on sensitivity of the gustatory system

    Directory of Open Access Journals (Sweden)

    Zverev Yuriy P

    2004-02-01

    Full Text Available Abstract Background Sensitivity of the gustatory system could be modulated by a number of short-term and long-term factors such as body mass, gender, age, local and systemic diseases and pathological processes, excessive alcohol drinking, drug dependence, smoking, composition of oral fluid, state of oral hygiene, consumption of some foods among many others. A few studies have demonstrated the effects of hunger and caloric satiety on sensitivity of the gustatory system in obese humans and animals. The aim of the present study was to assess the effects of short-term caloric deprivation and satiety on recognition taste thresholds of healthy, non-smoking, non-drinking, non-obese young male subjects. The two-alternative forced-choice technique was used to measure taste threshold. Results Recognition thresholds for sucrose and salt were significantly lower during fasting state than after a meal (t = 2.23, P Conclusions Short-term caloric deprivation in our study model was associated with increased taste sensitivity to sweet and salty substances compared to satiated state while taste sensitivity to bitter substances was not affected by the conditions of measurements. Selective modulation of sensitivity of the gustatory system might reflect the different biological importance of salty, sweet and bitter qualities of taste.

  16. Importance of silvopastoral systems on caloric stress reduction in tropical livestock productions

    Directory of Open Access Journals (Sweden)

    Alexander Navas Panadero

    2010-06-01

    Full Text Available Livestock systems in Colombia have been developed taking concepts and technologies from the green revolution, where gramineous monocrop is privileged over arboreal cover in grazing lands. This model has not taken into account the climatic conditions of the different tropical ecosystems, in which variables as temperature, relative humidity and evaporation can limit the animal´s productive and reproductive efficiency, besides being a risk factor for illness occurrence in the herd. Bos Taurus and Bos Indicus breeds show termoneutral ranges where its genetic potential can be express. However, out of this comfort area animals can enter in caloric stress which in consequence reduces its performance and sometimes can end up causing death. Silvopastoral systems comprise several functions; it contributes to lessen caloric stress since temperature under the tree canopy can reach between 2 and 9°C lower in comparison to open pastures. Differences in temperature reduction have been found among silvopastoral systems and species, being the tree group arrangements and the species with high density canopy, those with superior effect. Interactions among components should be analyzed in order to design systems that incorporate enough arboreal cover to achieve caloric stress reductions, but without affecting forage production in pastures. Silvopastoral systems contribute to improve animal welfare.

  17. Fluid-structural dynamics of ground-based and microgravity caloric tests

    Science.gov (United States)

    Kassemi, M.; Oas, J. G.; Deserranno, Dimitri

    2005-01-01

    Microgravity caloric tests aboard the 1983 SpaceLab1 mission produced nystagmus results with an intensity comparable to those elicited during post- and pre- flight tests, thus contradicting the basic premise of Barany's convection hypothesis for caloric stimulation. In this work, we present a dynamic fluid structural analysis of the caloric stimulation of the lateral semicircular canal based on two simultaneous driving forces for the endolymphatic flow: natural convection driven by the temperature-dependent density variation in the bulk fluid and expansive convection caused by direct volumetric displacement of the endolymph during the thermal irrigation. Direct numerical simulations indicate that on earth, the natural convection mechanism is dominant. But in the microgravity environment of orbiting spacecraft, where buoyancy effects are mitigated, expansive convection becomes the sole mechanism for producing cupular displacement. A series of transient 1 g and microgravity case studies are presented to delineate the differences between the dynamics of the 1 g and microgravity endolymphatic flows. The impact of these different flow dynamics on the endolymph-cupula fluid-structural interactions is also analyzed based on the time evolutions of cupular displacement and velocity and the transcupular pressure differences.

  18. Cervical vestibular evoked myogenic potentials and caloric test results in individuals with auditory neuropathy spectrum disorders.

    Science.gov (United States)

    Sujeet, Kumar Sinha; Niraj, Kumar Singh; Animesh, Barman; Rajeshwari, G; Sharanya, R

    2014-01-01

    Auditory neuropathy spectrum disorder is a type of hearing loss where outer hair cell function are normal (as evidenced by the preservation of OAEs and cochlear microphonics), whereas auditory nerve functions are abnormal (as evidenced by abnormal auditory brainstem evoked potentials beginning with wave I of the ABR) and acoustic reflexes to ipsilateral and contralateral tones are absent. It is likely that in cases with auditory neuropathy spectrum disorder not only the cochlear nerve, but also the vestibular nerves might get involved. The present study was conducted with an aim of finding out the inferior and superior vestibular nerve involvement through cervical vestibular evoked myogenic potentials and Caloric test results respectively in individuals with Auditory Neuropathy Spectrum Disorders. Total 26 participants who fulfilled the criteria of auditory neuropathy spectrum disorder participated for the study. Vestibular evoked myogenic potentials results showed absence of responses from most of the subjects also caloric responses showed bilateral hypofunctional responses in most of the participants, which is suggestive of involvement of both the inferior as well as superior vestibular nerve in individuals with auditory neuropathy spectrum disorders. Additionally there was no association between the pattern and degree of hearing loss to caloric test results and vestibular evoked myogenic potentials results findings.

  19. Subjective Visual Vertical during Caloric Stimulation in Healthy Subjects: Implications to Research and Neurorehabilitation

    Directory of Open Access Journals (Sweden)

    Martha Funabashi

    2015-01-01

    Full Text Available Background. The subjective visual vertical (SVV is a perception often impaired in patients with neurologic disorders and is considered a sensitive tool to detect otolithic dysfunctions. However, it remains unclear whether the semicircular canals (SCCs are also involved in the visual vertical perception. Objective. The aim of this study was to analyze the influence of horizontal SCCs on SVV by caloric stimulation in healthy subjects. Methods. SVV was performed before and during the ice-cold caloric stimulation (4°C, right ear in 30 healthy subjects. Results. The mean SVV tilts before and during the caloric stimulation were 0.31° ± 0.39 and −0.28° ± 0.40, respectively. There was no significant difference between the mean SVV tilts before and during stimulation p=0.113. Conclusion. These results suggest that horizontal SCCs do not influence SVV. Therefore, investigations and rehabilitation approaches for SVV misperceptions should be focused on otolithic and cognitive strategies.

  20. Feeding preference of adult females of ribbonfish Trichiurus lepturus through prey proximate-composition and caloric values

    Directory of Open Access Journals (Sweden)

    Vanessa Trindade Bittar

    Full Text Available In the present study we analysed the proximate-composition and caloric values of the preferred prey consumed by ribbonfish, Trichiurus lepturus L. 1758 (adult females, that are distributed in the inner continental shelf from northern Rio de Janeiro State, southeastern Brazil (~22ºS, assessing the potential of nutritional and energetic approach as a tool to understand the feeding selective pattern of this marine top carnivore. The preferred prey of this predator composed of fish co-specifics, Pellona harroweri, Chirocentrodon bleekerianus, Lycengraulis grossidens, Peprilus paru, squid Doryteuthis plei, and shrimp Xiphopenaeus kroyeri were collected from 2007 to 2010 for proximate-composition (water, protein, lipid, ash, and carbohydrate and caloric value analyses. The correspondence analysis showed that protein is the main component in the prey species (61.32% of variance explained, standing out from the other nutrients. Lipid has the highest percentage related to L. grossidens, ash to X. kroyeri and carbohydrate to D. plei. The strong correlations between protein and caloric value (positive and lipid and caloric value (negative indicated that T. lepturus is attending its energy demand through the prey protein content. This work elucidated the feeding preference of adult females of T. lepturus in relation to nutritional and caloric content of their preferred prey. The species showed food selectivity to prey that provide more energy per ingested biomass, so that the feeding events can maximize the predator's caloric gain, which is obtained by a protein-based diet.

  1. Economic management of vertigo/dizziness disease in a county hospital: video-head-impulse test vs. caloric irrigation.

    Science.gov (United States)

    Rambold, Holger A

    2015-10-01

    The video-head-impulse test (vHIT) is an important test for examining unilateral vestibular hypofunction. Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies have shown that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. This retrospective study reproduces those finding in a much larger group of patients at a county hospital. 1063 patients were examined with the vHIT and bithermal caloric irrigation on the same day and analyzed with respect to side differences. Of those patients 13.3% had pathological vHIT and a caloric irrigation test, 4.6% a pathological vHIT only and 24.1% a pathologic caloric test only. As both tests might be necessary, we calculated the optimal sequence of the two examinations based on savings in time for the different disease groups. Especially in vestibular failure using the vHIT first and only applying the caloric irrigation in case of an unremarkable vHIT saves time and optimizes the diagnostic work up. In contrast, in Menière's disease and vestibular migraine testing caloric irrigation first might be more efficient.

  2. Saccharin and aspartame, compared with sucrose, induce greater weight gain in adult Wistar rats, at similar total caloric intake levels.

    Science.gov (United States)

    Feijó, Fernanda de Matos; Ballard, Cíntia Reis; Foletto, Kelly Carraro; Batista, Bruna Aparecida Melo; Neves, Alice Magagnin; Ribeiro, Maria Flávia Marques; Bertoluci, Marcello Casaccia

    2013-01-01

    It has been suggested that the use of nonnutritive sweeteners (NNSs) can lead to weight gain, but evidence regarding their real effect in body weight and satiety is still inconclusive. Using a rat model, the present study compares the effect of saccharin and aspartame to sucrose in body weight gain and in caloric intake. Twenty-nine male Wistar rats received plain yogurt sweetened with 20% sucrose, 0.3% sodium saccharin or 0.4% aspartame, in addition to chow and water ad libitum, while physical activity was restrained. Measurements of cumulative body weight gain, total caloric intake, caloric intake of chow and caloric intake of sweetened yogurt were performed weekly for 12 weeks. Results showed that addition of either saccharin or aspartame to yogurt resulted in increased weight gain compared to addition of sucrose, however total caloric intake was similar among groups. In conclusion, greater weight gain was promoted by the use of saccharin or aspartame, compared with sucrose, and this weight gain was unrelated to caloric intake. We speculate that a decrease in energy expenditure or increase in fluid retention might be involved.

  3. Telomere shortening in diaphragm and tibialis anterior muscles of aged mdx mice.

    Science.gov (United States)

    Lund, Troy C; Grange, Robert W; Lowe, Dawn A

    2007-09-01

    The progression of Duchenne muscular dystrophy (DMD) is, in part, due to satellite cell senescence driven by high replicative pressure as these muscle stem cells repeatedly divide and fuse to damaged muscle fibers. We hypothesize that telomere shortening in satellite cells underlies their senescence. To test this hypothesis, we evaluated the diaphragm and a leg muscle from dystrophic mice of various ages for telomere dynamics. We found 30% telomere shortening in tibialis anterior muscles from 600-day-old mdx mice relative to age-matched wildtype mice. We also found a more severe shortening of telomere length in diaphragm muscles of old mdx mice. In those muscles, telomeres were shortened by approximately 15% and 40% in 100- and 600-day-old mdx mice, respectively. These findings indicate that satellite cells undergo telomere erosion, which may contribute to the inability of these cells to perpetually repair DMD muscle.

  4. Effects of fiber type on force depression after active shortening in skeletal muscle.

    Science.gov (United States)

    Joumaa, V; Power, G A; Hisey, B; Caicedo, A; Stutz, J; Herzog, W

    2015-07-16

    The aim of this study was to investigate force depression in Type I and Type II muscle fibers. Experiments were performed using skinned fibers from rabbit soleus and psoas muscles. Force depression was quantified after active fiber shortening from an average sarcomere length (SL) of 3.2µ m to an average SL of 2.6 µm at an absolute speed of 0.115f iber length/s and at a relative speed corresponding to 17% of the unloaded shortening velocity (V0) in each type of fibers. Force decay and mechanical work during shortening were also compared between fiber types. After mechanical testing, each fiber was subjected to myosin heavy chain (MHC) analysis in order to confirm its type (Type I expressing MHC I, and Type II expressing MHC IId). Type II fibers showed greater steady-state force depression after active shortening at a speed of 0.115 fiber length/s than Type I fibers (14.5±1.5% versus 7.8±1.7%). Moreover, at this absolute shortening speed, Type I fibers showed a significantly greater rate of force decay during shortening and produced less mechanical work than Type II fibers. When active shortening was performed at the same relative speed (17% V0), the difference in force depression between fiber types was abolished. These results suggest that no intrinsic differences were at the origin of the disparate force depressions observed in Type I and Type II fibers when actively shortened at the same absolute speed, but rather their distinct force-velocity relationships.

  5. Caloric beverages were major sources of energy among children and adults in Mexico, 1999-2012.

    Science.gov (United States)

    Stern, Dalia; Piernas, Carmen; Barquera, Simon; Rivera, Juan A; Popkin, Barry M

    2014-06-01

    Mexico, with 1 of the highest obesity prevalences in the world, instituted a 10% excise tax for any sugar-sweetened beverage (SSB) starting on 1 January 2014. Understanding the recent patterns and trends in beverage intake and sales in Mexico provides both background and baseline data for the importance of SSBs and other beverages in the Mexican diet. We analyzed a single 24-h dietary recall from 2 nationally representative surveys: the Mexican Nutrition Survey 1999 (n = 6049) and the National Health and Nutrition Survey 2012 (n = 10,343). To describe trends and patterns in beverages, we calculated the volume and energy intake per capita and per consumer and the proportion of consumers of each beverage group in each survey. A commercial sales dataset was used to describe beverage sales trends from 1999 to 2012. From 1999 to 2012, total daily energy from beverages increased among children aged 5-11 y (+45.3 kcal), females aged 12-19 y (+57.3 kcal), and adult females aged 20-49 y (+96.4 kcal) (P agua fresca (fruit water made in stalls or at home, usually with added sugars), and fruit drinks among children aged 5-11 y and females aged 12-19 y and caloric coffee/tea, soda, and agua fresca among adult females aged 20-49 y. In 2012, beverages represented 17.5% (325 kcal) and 19.0% (382 kcal) of the total daily energy intake per capita in children aged 1-19 y and adults aged ≥20 y, respectively. In 2012, flavored milk beverages, caloric soda, and high-fat milk were the top 3 major contributors to total daily energy intake per capita in all children aged 1-19 y. Caloric soda, caloric coffee/tea, and agua fresca were the top 3 major energy contributors in adults aged ≥20 y. From 1999 to 2012, sales of soda, fruit-flavored drinks, and flavored waters increased. In conclusion, consumption of several beverages with added sugars increased among children and adult females in Mexico. Because caloric soda is currently 1 of the top beverages consumed, a 10% tax on SSBs might

  6. Restricted and quasi-toral restricted Lie-Rinehart algebras

    Directory of Open Access Journals (Sweden)

    Sun Bing

    2015-09-01

    Full Text Available In this paper, we introduce the definition of restrictable Lie-Rinehart algebras, the concept of restrictability is by far more tractable than that of a restricted Lie-Rinehart algebra. Moreover, we obtain some properties of p-mappings and restrictable Lie-Rinehart algebras. Finally, we give some sufficient conditions for the commutativity of quasi-toral restricted Lie-Rinehart algebras and study how a quasi-toral restricted Lie-Rinehart algebra with zero center and of minimal dimension should be.

  7. Could an increase in airway smooth muscle shortening velocity cause airway hyperresponsiveness?

    Science.gov (United States)

    Bullimore, Sharon R; Siddiqui, Sana; Donovan, Graham M; Martin, James G; Sneyd, James; Bates, Jason H T; Lauzon, Anne-Marie

    2011-01-01

    Airway hyperresponsiveness (AHR) is a characteristic feature of asthma. It has been proposed that an increase in the shortening velocity of airway smooth muscle (ASM) could contribute to AHR. To address this possibility, we tested whether an increase in the isotonic shortening velocity of ASM is associated with an increase in the rate and total amount of shortening when ASM is subjected to an oscillating load, as occurs during breathing. Experiments were performed in vitro using 27 rat tracheal ASM strips supramaximally stimulated with methacholine. Isotonic velocity at 20% isometric force (Fiso) was measured, and then the load on the muscle was varied sinusoidally (0.33 ± 0.25 Fiso, 1.2 Hz) for 20 min, while muscle length was measured. A large amplitude oscillation was applied every 4 min to simulate a deep breath. We found that: 1) ASM strips with a higher isotonic velocity shortened more quickly during the force oscillations, both initially (P shortening during the force oscillation protocol (P shortening with increased isotonic velocity could be explained by a change in either the cycling rate of phosphorylated cross bridges or the rate of myosin light chain phosphorylation. We conclude that, if asthma involves an increase in ASM velocity, this could be an important factor in the associated AHR.

  8. Compression and Combining Based on Channel Shortening and Rank Reduction Technique for Cooperative Wireless Sensor Networks

    KAUST Repository

    Ahmed, Qasim Zeeshan

    2013-12-18

    This paper investigates and compares the performance of wireless sensor networks where sensors operate on the principles of cooperative communications. We consider a scenario where the source transmits signals to the destination with the help of L sensors. As the destination has the capacity of processing only U out of these L signals, the strongest U signals are selected while the remaining (L?U) signals are suppressed. A preprocessing block similar to channel-shortening is proposed in this contribution. However, this preprocessing block employs a rank-reduction technique instead of channel-shortening. By employing this preprocessing, we are able to decrease the computational complexity of the system without affecting the bit error rate (BER) performance. From our simulations, it can be shown that these schemes outperform the channel-shortening schemes in terms of computational complexity. In addition, the proposed schemes have a superior BER performance as compared to channel-shortening schemes when sensors employ fixed gain amplification. However, for sensors which employ variable gain amplification, a tradeoff exists in terms of BER performance between the channel-shortening and these schemes. These schemes outperform channel-shortening scheme for lower signal-to-noise ratio.

  9. Restriction of Helmholtz Model

    Directory of Open Access Journals (Sweden)

    V.M. Polunin

    2014-07-01

    Full Text Available The results of the experimental studies of physical mechanisms of energy dissipation in the oscillating system in which air cavity held by the forces of magnetic levitation is used as the elastic element, and magnetic fluid prepared on the basis of dispersing media with different viscosity level is used as the inertial element are considered in the article. Based on the obtained results the conclusion on the restriction of the applicability of Helmholtz equation, caused by boundary effects is made.

  10. License restrictions at Barnwell

    Energy Technology Data Exchange (ETDEWEB)

    Autry, V.R. [S.C. Dept. of Health and Environmental Control, Columbia, SC (United States). Bureau of Radiological Health

    1991-12-31

    The State of South Carolina was delegated the authority by the US Nuclear Regulatory Commission to regulate the receipt, possession, use and disposal of radioactive material as an Agreement State. Since 1970, the state has been the principal regulatory authority for the Barnwell Low-Level Waste Disposal Facility operated by Chem-Nuclear Systems, Inc. The radioactive material license issued authorizing the receipt and disposal of low-level waste contains numerous restrictions to ensure environmental protection and compliance with shallow land disposal performance criteria. Low-level waste has evolved from minimally contaminated items to complex waste streams containing high concentrations of radionuclides and processing chemicals which necessitated these restrictions. Additionally, some waste with their specific radionuclides and concentration levels, many classified as low-level radioactive waste, are not appropriate for shallow land disposal unless additional precautions are taken. This paper will represent a number of these restrictions, the rationale for them, and how they are being dealt with at the Barnwell disposal facility.

  11. Control of pre-Cenozoic extensional heterogeneities on the kinematics of Cenozoic shortening: Northwestern Argentina

    Science.gov (United States)

    Pearson, D. M.; Kapp, P. A.; Reiners, P. W.; Gehrels, G. E.

    2012-12-01

    Results from regional-scale mapping and structural analysis, (U-Th)/He and U-Pb age dating of apatite and zircon, and a regional balanced cross section allow us to build upon the pre-existing geological framework for the retroarc of northwestern Argentina. Coupled with previous work in the region, our results suggest that the style, distribution, and kinematics of shortening in the Eastern Cordillera and Santa Bárbara tectonomorphic provinces of the thrust belt at this latitude (24-25°S) were strongly influenced by the architecture of a Mesozoic rift system. In contrast to the thin-skinned Subandean fold-thrust belt of southern Bolivia where structures are primarily W-dipping and propagated progressively eastward through time, reverse faults in northwestern Argentina are more variably oriented, steeply E-dipping, locally inverted structures that propagated in an overall eastward direction in a much more sporadic manner. The first major eastward propagation event at this latitude occurred at ~40 Ma and is expressed as Eocene (U-Th)/He apatite and zircon ages coincident with the western arm of the Cretaceous Salta rift system. Other workers also documented angular unconformities of this age in the western and eastern arms of the rift system. Up until ~10 Ma, deformation and exhumation were restricted to the western margin of the Cretaceous rift in the western Eastern Cordillera and eastern margin of the Puna plateau. This was followed by an ~75 km jump in the location of the thrust front toward the east to bypass the central portion of a horst block of the Cretaceous rift system, followed by subsequent initiation of new E-dipping reverse faults in a subsystem that propagated toward the west into this pre-existing structural high. During Pliocene time, deformation again migrated >100 km eastward to a Cretaceous syn-rift depocenter in the Santa Bárbara Ranges and was likely followed by additional westward propagation to the current location of deformation with the

  12. Telomeres shorten more slowly in slow-aging wild animals than in fast-aging ones.

    Science.gov (United States)

    Dantzer, Ben; Fletcher, Quinn E

    2015-11-01

    Research on the physiological causes of senescence aim to identify common physiological mechanisms that explain age-related declines in fitness across taxonomic groups. Telomeres are repetitive nucleotide sequences found on the ends of eukaryotic chromosomes. Past research indicates that telomere attrition is strongly correlated with inter-specific rates of aging, though these studies cannot distinguish whether telomere attrition is a cause or consequence of the aging process. We extend previous research on this topic by incorporating recent studies to test the hypothesis that telomeres shorten more slowly with age in slow-aging animals than in fast-aging ones. We assembled all studies that have quantified cross-sectional (i.e. between-individual) telomere rates of change (TROC) over the lifespans of wild animals. This included 22 estimates reflecting absolute TROC (TROCabs, bp/yr, primarily measured using the terminal restriction fragment length method), and 10 estimates reflecting relative TROC (TROCrel, relative telomere length/yr, measured using qPCR), from five classes (Aves, Mammalia, Bivalvia, Reptilia, and Actinopterygii). In 14 bird species, we correlated between-individual (i.e. cross-sectional) TROCabs estimates with both maximum lifespan and a phylogenetically-corrected principle component axis (pcPC1) that reflected the slow-fast axis of life-history variation. Bird species characterized by faster life-histories and shorter maximum lifespans had faster TROCabs. In nine studies, both between-individual and within-individual TROC estimates were available (n=8 for TROCabs, n=1 for TROCrel). Within-individual TROC estimates were generally greater than between-individual TROC estimates, which is indicative of selective disappearance of individuals with shorter telomeres. However, the difference between within- and between-individual TROC estimates was only significant in two out of nine studies. The relationship between within-individual TROCabs and maximum

  13. Depressant effect of active shortening in the anterior byssus retractor muscle of Mytilus edulis.

    Science.gov (United States)

    Ekelund, M C

    1983-03-01

    The effect of shortening during activity, previously characterized in vertebrate striated muscle, was investigated in the anterior byssus retractor muscle (ABRM) of the mollusc Mytilus edulis. This muscle is considered to have an essentially myosin-linked Ca2+-regulatory system. Release steps of different amplitude were performed during isometric phasic contraction, and force redevelopment was recorded at a muscle length L1, defined as 90% of the muscle length at which a slight resting tension, approximately 1 mN, appeared in the presence of 2.5 X 10(-5) M 5-HT. Active shortening caused a graded depression of the contractile force without affecting the total duration of the mechanical response. Peak redeveloped force after muscle shortening of 0.06 L1 and 0.18 L1 was reduced by approximately 1.5% and 7.0%, respectively, of the isometric tension value at L1. The shortening effect was fully reversible, and had a lifetime of approximately 8 to 9 s. The depressant effect of active shortening was augmented at a reduced degree of activation of the muscle. The presence of caffeine and dantrolene and altered tonicity of the extracellular medium (0.9 T-1.2 T) did not significantly affect the shortening induced depression obtained at maximum phasic activation of the preparation. The nature of the shortening effect is compared to that obtained in vertebrate striated muscle and is discussed on the basis of differences in Ca2+-regulation of the contractile system in these two muscles.

  14. Diaphragm curvature modulates the relationship between muscle shortening and volume displacement.

    Science.gov (United States)

    Greybeck, Brad J; Wettergreen, Matthew; Hubmayr, Rolf D; Boriek, Aladin M

    2011-07-01

    During physiological spontaneous breathing maneuvers, the diaphragm displaces volume while maintaining curvature. However, with maximal diaphragm activation, curvature decreases sharply. We tested the hypotheses that the relationship between diaphragm muscle shortening and volume displacement (VD) is nonlinear and that curvature is a determinant of such a relationship. Radiopaque markers were surgically placed on three neighboring muscle fibers in the midcostal region of the diaphragm in six dogs. The three-dimensional locations were determined using biplanar fluoroscopy and diaphragm VD, curvature, and muscle shortening were computed in the prone and supine postures during spontaneous breathing (SB), spontaneous inspiration efforts after airway occlusion at lung volumes ranging from functional residual capacity (FRC) to total lung capacity, and during bilateral maximal phrenic nerve stimulation at those same lung volumes. In supine dogs, diaphragm VD was approximately two- to three-fold greater during maximal phrenic nerve stimulation than during SB. The contribution of muscle shortening to VD nonlinearly increases with level of diaphragm activation independent of posture. During submaximal diaphragm activation, the contribution is essentially linear due to constancy of diaphragm curvature in both the prone and supine posture. However, the sudden loss of curvature during maximal bilateral phrenic nerve stimulation at muscle shortening values greater than 40% (ΔL/L(FRC)) causes a nonlinear increase in the contribution of muscle shortening to diaphragm VD, which is concomitant with a nonlinear change in diaphragm curvature. We conclude that the nonlinear relationship between diaphragm muscle shortening and its VD is, in part, due to a loss of its curvature at extreme muscle shortening.

  15. Spine biomechanics associated with the shortened, modern one-plane golf swing.

    Science.gov (United States)

    Dale, R Barry; Brumitt, Jason

    2016-06-01

    The purpose of this study was to compare kinetic, kinematic, and performance variables associated with full and shortened modern backswings in a skilled group of modern swing (one-plane) golfers. Shortening the modern golf backswing is proposed to reduce vertebral spine stress, but supporting evidence is lacking and performance implications are unknown. Thirteen male golfers performed ten swings of each swing type using their own 7-iron club. Biomechanical-dependent variables included the X-Factor kinematic data and spine kinetics. Performance-related dependent variables included club head velocity (CHV), shot distance, and accuracy (distance from the target line). Data were analysed with repeated measures ANOVA with an a priori alpha of 0.05 (SPSS 22.0, IBM, Armonk, NY, USA). We found significant reductions for the X-Factor (p < 0.05) between the full and shortened swings. The shortened swing condition ameliorated vertebral compression force from 7.6 ± 1.4 to 7.0 ± 1.7 N (normalised to body weight, p = 0.01) and significantly reduced CHV (p < 0.05) by ~2 m/s with concomitant shot distance diminution by ~10 m (p < 0.05). Further research is necessary to examine the applicability of a shortened swing for golfers with low back pain.

  16. The effect of muscle length on force depression after active shortening in soleus muscle of mice.

    Science.gov (United States)

    Van Noten, Pieter; Van Leemputte, Marc

    2011-07-01

    Isometric muscle force after active shortening is reduced [force depression (FD)]. The mechanism is incompletely understood but work delivered during shortening has been suggested to be the main determinant of FD. However, whether muscle length affects the sensitivity of FD to work is unknown, although this information might add to the understanding of the phenomenon. The aim of this study is to investigate the length dependence of the FD/work ratio (Q). Therefore, isometric force production (ISO) of 10 incubated mouse soleus muscles was compared to isometric force after 0.6, 1.2, and 2.4 mm shortening (IAS) at different end lengths ranging from L(0) - 3 to L(0) + 1.8 mm in steps of 0.6 mm. FD was calculated as the force difference between an ISO and IAS contraction at the same activation time (6 s) and end length. We confirm the strong relation between FD and work at L(0) (R² = 0.92) and found that FD is length dependent with a maximum of 8.8 ± 0.3% at L(0) + 1.2 mm for 0.6 mm shortening amplitude. Q was only constant for short muscle lengths (muscle length. The observed length dependence of Q indicates that FD is not only determined by work produced during shortening but also by a length-dependent factor, possibly actin compliance, which should be incorporated in any mechanism explaining FD.

  17. Olas de calor e influencia urbana en Madrid y su área metropolitana

    Directory of Open Access Journals (Sweden)

    Fernández García, F.

    2008-12-01

    Full Text Available The frequency and duration of the warmest temperature episodes, a common phenomenon under the continental Mediterranean conditions of the Spanish Southern Meseta, has increased in the Madrid area since the 80´s, although their magnitude remains unchanged. The effect of the urban environment on those extreme events has exacerbated the heat load due to the persistence of the high temperatures along the night time hours. Nevertheless, the diversity of the urban morphology introduces a spatial variability on the strength of this nocturnal heat load, aggravating it in the densely urbanized areas and mitigating it in the vicinities of the green areas.

    La frecuencia y duración de los episodios cálidos extremos, un fenómeno habitual en el clima mediterráneo continental de la Meseta Meridional, ha aumentado en el área de Madrid desde los años noventa, aunque su magnitud permanece constante. En el interior de la aglomeración urbana, el efecto general de la ciudad sobre estos eventos climáticos extremos ha supuesto una exacerbación del calor, no tanto por un aumento de la temperatura máxima, como por una persistencia del calor en las horas nocturnas. No obstante, la diversidad de la morfología urbana introduce variaciones espaciales en la intensidad de este calor nocturno, agravando sus efectos en las áreas densamente urbanizadas y mitigándolos en las proximidades de las áreas verdes.

  18. Lost in processing? Perceived healthfulness, taste and caloric content of whole and processed organic food.

    Science.gov (United States)

    Prada, Marília; Garrido, Margarida V; Rodrigues, David

    2017-03-23

    The "organic" claim explicitly informs consumers about the food production method. Yet, based on this claim, people often infer unrelated food attributes. The current research examined whether the perceived advantage of organic over conventional food generalizes across different organic food types. Compared to whole organic foods, processed organic foods are less available, familiar and prototypical of the organic food category. In two studies (combined N = 258) we investigated how both organic foods types were perceived in healthfulness, taste and caloric content when compared to their conventional alternatives. Participants evaluated images of both whole (e.g., lettuce) and processed organic food exemplars (e.g., pizza), and reported general evaluations of these food types. The association of these evaluations with individual difference variables - self-reported knowledge and consumption of organic food, and environmental concerns - was also examined. Results showed that organically produced whole foods were perceived as more healthful, tastier and less caloric than those produced conventionally, thus replicating the well-established halo effect of the organic claim in food evaluation. The organic advantage was more pronounced among individuals who reported being more knowledgeable about organic food, consumed it more frequently, and were more environmentally concerned. The advantage of the organic claim for processed foods was less clear. Overall, processed organic (vs. conventional) foods were perceived as tastier, more healthful (Study 1) or equally healthful (Study 2), but also as more caloric. We argue that the features of processed food may modulate the impact of the organic claim, and outline possible research directions to test this assumption. Uncovering the specific conditions in which food claims bias consumer's perceptions and behavior may have important implications for marketing, health and public-policy related fields.

  19. Effects of emodin on treating murine nonalcoholic fatty liver induced by high caloric laboratory chaw

    Institute of Scientific and Technical Information of China (English)

    Hui Dong; Fu-Er Lu; Zhi-Qiang Gao; Li-Jun Xu; Kai-Fu Wang; Xin Zou

    2005-01-01

    AIM: To investigate the effects of emodin on the treatment of non-alcoholic fatty liver in rats induced by high caloric laboratory chaw.METHODS: Non-alcoholic fatty liver model was successfully established by feeding with high caloric laboratory chaw for 12 wk. Then the model rats were randomly divided into 3 groups, namely model control group, emodin group and dietary treatment group. The rats in emodin group in othergroups were given distilled water of the same volume. The rats in model control group were fed with high caloric laboratory chaw while animals in other groups were fed with normal diet. Four weeks later, liver index (liver/body weight ratio), serum activities of liver-associated enzymes, blood lipid, fasting blood glucose, fasting plasma insulin, HOMA insulin resistance index (HOMA-IR), hepatic triglyceride content and histology features of all groups were assayed. The expression of hepatic peroxisomal proliferator activated receptor (PPAR) gamma was determined by RT-PCR.RESULTS: The body weight, liver index, serum activities of alanine aminotransferase (ALT), blood lipid, hepatic triglyceride content of model control group were significantly elevated, with moderate to severe hepatocyte steatosis.The expression of hepatic PPAR gamma mRNA was obviously reduced in model control group. Compared with model control group, the body weight, liver index, serum activities of ALT, blood lipids and hepatic triglyceride of emodin group significantly decreased and hepatic histology display was also greatly improved. Meanwhile, the expression of hepatic PPAR gamma mRNA was elevated.However, high serum activities of ALT and hyperlipidemia were persisted in dietary treatment group although liver index was decreased and liver histology was somewhat improved.CONCLUSION: It is suggested that emodin might be effective in the treatment of non-alcoholic fatty liver in rats. Its therapeutic mechanism could be associated with increasing the expression of hepatic PPAR gamma mRNA.

  20. Evaluation of a direct contact heat exchanger; Evaluacion de un intercambiador de calor de contacto directo

    Energy Technology Data Exchange (ETDEWEB)

    Siqueiros, J.; Bonilla, O. [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1997-12-31

    In this paper the application areas of the direct contact heat exchangers is discussed, as well as its main characteristics. A description is made of the experimental equipment designed and built at pilot scale including the instrumentation employed. The methodology employed as well as the analysis and the discussion of the results are also presented. [Espanol] Se mencionan las areas de aplicacion de los intercambiadores de calor de contacto directo, asi como sus caracteristicas principales. Se describe el equipo experimental a nivel piloto disenado y construido incluyendo la instrumentacion utilizada. Se presenta la metodologia empleada asi como el analisis y discusion de los resultados.

  1. Rapid relief of thalamic pain syndrome induced by vestibular caloric stimulation.

    Science.gov (United States)

    Ramachandran, Vilayanur S; McGeoch, Paul D; Williams, Lisa; Arcilla, Gerard

    2007-06-01

    Central post-stroke pain syndrome develops in a minority of patients following a stroke. The most usual causative lesion involves the lateral thalamus. The classic presentation is of severe, unrelenting pain that involves the entire contralateral half of the body. It is largely refractory to current treatments. We found that in two patients with this condition their pain was substantially improved by vestibular caloric stimulation, whereas placebo procedures had no effect. We proposed that this is because vestibular stimulation activates the posterior insula, which in turn inhibits the generation of pain in the anterior cingulate.

  2. On entropy change measurements around first order phase transitions in caloric materials

    Science.gov (United States)

    Caron, Luana; Doan, Nguyen Ba; Ranno, Laurent

    2017-02-01

    In this work we discuss the measurement protocols for indirect determination of the isothermal entropy change associated with first order phase transitions in caloric materials. The magneto-structural phase transitions giving rise to giant magnetocaloric effects in Cu-doped MnAs and FeRh are used as case studies to exemplify how badly designed protocols may affect isothermal measurements and lead to incorrect entropy change estimations. Isothermal measurement protocols which allow correct assessment of the entropy change around first order phase transitions in both direct and inverse cases are presented.

  3. Tecnologías emergentes para la conservación de alimentos sin calor

    OpenAIRE

    Fernández Molina, Juan José; Gustavo V. Barbosa-Cánovas; Swanson, Barry G.

    2001-01-01

    Not available

    Se han investigado los principios básicos de tres tecnologías emergentes para pasteurizar y esterilizar alimentos sin empleo del calor Mediante numerosos estudios se ha comprobado la efectividad de los campos eléctricos pulsantes de alta intensidad (CEPAI), los pulsos de luz (PL) y los campos magnéticos oscilantes (CMO) en la destrucción de microorganismos y enzimas de sistemas alimentarios. En la inactivación microbiana por CEPA!, el blanco principal es la me...

  4. The minimal caloric test asymmetric response in vertigo-free migraine patients

    Directory of Open Access Journals (Sweden)

    Eliana Teixeira Maranhão

    2016-02-01

    Full Text Available ABSTRACT Vertigo symptoms and subclinical vestibular dysfunctions may occur in migraine. The Minimal Caloric Test (MCT, an easy-to-perform, convenient and yet informative procedure was used to test the vestibular function in 30 vertigo-free migraine patients outside attacks and 30 paired controls. Although not statistically significant, a right-to-left nystagmus duration asymmetry greater than 25% was present in both groups. This difference was greater in the patients group, suggesting the presence of subclinical vestibular imbalance in migraine.

  5. Vertigo and cerebral hemoglobin changes during unilateral caloric stimulation: a near-infrared spectroscopy study.

    Science.gov (United States)

    Iida, Masahiro; Haida, Munetaka; Igarashi, Makoto

    2009-05-01

    The aim of the present study using near-infrared spectroscopy (NIRS) is to evaluate the correlation of cerebral (parieto-temporal lobe) hemoglobin changes and vertiginous sensation during unilateral caloric stimulation. During the hot water (44 degrees C) stimulus, cerebral hemoglobin was increased bilaterally, but it was dominant ipsilaterally. During the unilateral cold water (30 degrees C) stimulus, cerebral hemoglobin was decreased on both sides, especially on the ipsilateral side. Vertigious sensation was strong in cases with marked left-right difference of cerebral hemoglobin changes. The usefulness of NIRS to investigate the relationship between peripheral vestibular organ and vestibular cortex was verified.

  6. Dimensionamiento de intercambiadores de calor de coraza y tubos, con ayuda de computador

    Directory of Open Access Journals (Sweden)

    Gabriel Eduardo Rocha Camino

    2011-02-01

    Full Text Available En este trabajo se plantea el problema de optimizar el diseño de un intercambiador de calor del tipo coraza y tubos, y se propone un método para resolverlo, con base en la técnica del "estudio paramétrico de la respuesta". Además, se muestra la necesidad de utilizar el computador como herramienta para Implementar dicho método, y se describe un programa escrito con tal fin.

  7. Transferencia molecular de calor, masa y/o cantidad de movimiento

    OpenAIRE

    Betancourt Grajales, Ramiro

    2008-01-01

    Este texto fue diseñado para proveer un tratamiento integrado de las tres áreas del transporte: impulso, calor y masa. Las similitudes entre las leyes de flujo permiten aplicar directamente analogías en el cálculo del transporte haciendo una economía en el esfuerzo docente–discente acorde con las pedagogías intensivas. Muchas de las ecuaciones básicas son matemáticamente idénticas cuando se expresan en términos de las variables y densidades de flujo generalizadas. El texto comienza con tra...

  8. Normal physical activity obliterates the deleterious effects of high-caloric intake

    DEFF Research Database (Denmark)

    Krogh-Madsen, Rikke; Pedersen, Maria; Solomon, Thomas

    2013-01-01

    magnetic resonance imaging (MRI)- scans, continuous glucose monitoring (CGM), and oral glucose tolerance tests (OGTT) with stable isotopes were performed before and after the intervention. Both study groups gained the same amount of body weight. However, the inactive group accumulated significantly more....... Therefore, healthy individuals on a high caloric intake were randomized to either 10,000 or 1,500 steps per day for 14 days. Step-number, total energy expenditure, dietary records, neuropsychological tests, maximal oxygen uptake (VO2max), whole body dual-energy X-ray absorptiometry (DXA)- and abdominal...

  9. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    OpenAIRE

    2011-01-01

    Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch), ½ Charolais ½ Brahman (CB), Holstein (H) y Jersey (J). Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas) la frecuencia respiratoria (FR) y temperatura rectal (TR). Se registraron las variables climáticas para calcular el índice de temperatura-hum...

  10. The effects of music on the selected stress behaviors, weight, caloric and formula intake, and length of hospital stay of premature and low birth weight neonates in a newborn intensive care unit.

    Science.gov (United States)

    Caine, J

    1991-01-01

    The purpose of this study was to examine the effects of music on selected stress behaviors, weight, caloric and formula intake, and length of hospital stay. Subjects were 52 preterm and low birth weight newborns in a newborn intensive care unit (NBICU) who were in stable condition and restricted to isolettes. Subjects in the experimental and control groups were matched for equivalency based on sex, birth weight, and diagnostic criticality. Eleven males and 15 females were assigned to the control group and received routine auditory stimulation. The experimental group of 11 males and 15 females received music stimulation, which consisted of approximately 60 minutes of tape recorded vocal music, including lullabies and children's music, and routine auditory stimulation. Thirty-minute segments of the recording were played alternatively with 30 minutes of routine auditory stimulation three times daily. Exposure to music stimulation occurred only during the infants' stay in the NBICU. Results suggest music stimulation may have significantly reduced initial weight loss, increased daily average weight, increased formula and caloric intake, significantly reduced length of the NBICU and total hospital stays, and significantly reduced the daily group mean of stress behaviors for the experimental group. Data analyses suggest the length of hospital stay may be correlated with the amount of stress experienced by the neonate and not with weight gains. Theoretical and practical aspects of these results are discussed.

  11. [Comparison of force and shortening velocity in fast and slow rabbit muscle fibers at different temperatures].

    Science.gov (United States)

    Kochubeĭ, P V; Bershitskiĭ, S Iu

    2014-01-01

    The temperature dependence of force, maximal shortening velocity and power of maximally activated single permeabilized fibers from fast and slow muscles of the rabbit were recorded in a temperature range from 10 to 35 degrees C with 5 degrees C step. It was found that temperature dependence of force of both types of fibers is identical. Averaged maximal shortening velocity in the slow fibers, unlike the fast fibers, had no statistically significant temperature dependence that is not in agreement with the data obtained on intact rat muscle fibers and in an in vitro motility assay. However maximal shortening velocity in each individual slow fiber did depend on temperature. The temperature dependence of power of the slow fibers was lower than that of the fast ones. Because of large data scattering the average temperature dependence of power of the slow fibers was significantly lower than that in individual slow fibers.

  12. Assessment of muscle shortening and static posture in children with persistent asthma.

    Science.gov (United States)

    Lopes, Erica A; Fanelli-Galvani, Adriana; Prisco, Camilla C V; Gonçalves, Raquel C; Jacob, Cristina M A; Cabral, Anna L B; Martins, Milton A; Carvalho, Celso R F

    2007-07-01

    Asthmatic patients experience an increase in airway resistance that overburdens both respiratory and non-respiratory muscles. The objective of the present study was to determine whether children with persistent asthma present muscle shortening and postural changes. The 60 boys evaluated, aged 7-12 (pubertal ages up to Tanner stage G2) were divided into three age- and BMI-matched groups of equal number: CON (no history of asthma or allergy); MPA (mild persistent asthma); SPA (severe persistent asthma). Pulmonary function, muscle shortening and static posture were evaluated. The SPA group presented higher protraction of the head and shoulder compared with the CON group [9.5 (6.0-12.0) degrees vs 5.5 (0.0-12.0) degrees, P control subjects in five out nine evaluated outcomes. Our data suggest that severe asthmatic children present postural adaptations and muscle shortening that seem to be related to disease severity.

  13. Comparison of different cooling regimes within a shortened liquid cooling/warming garment on physiological and psychological comfort during exercise

    Science.gov (United States)

    Leon, Gloria R.; Koscheyev, Victor S.; Coca, Aitor; List, Nathan

    2004-01-01

    The aim of this study was to compare the effectiveness of different cooling regime intensities to maintain physiological and subjective comfort during physical exertion levels comparable to that engaged in during extravehicular activities (EVA) in space. We studied eight subjects (six males, two females) donned in our newly developed physiologically based shortened liquid cooling/warming garment (SLCWG). Rigorous (condition 1) and mild (condition 2) water temperature cooling regimes were compared at physical exertion levels comparable to that performed during EVA to ascertain the effectiveness of a lesser intensity of cooling in maintaining thermal comfort, thus reducing energy consumption in the portable life support system. Exercise intensity was varied across stages of the session. Finger temperature, rectal temperature, and subjective perception of overall body and hand comfort were assessed. Finger temperature was significantly higher in the rigorous cooling condition and showed a consistent increase across exercise stages, likely due to the restriction of heat extraction because of the intensive cold. In the mild cooling condition, finger temperature exhibited an overall decline with cooling, indicating greater heat extraction from the body. Rectal temperature was not significantly different between conditions, and showed a steady increase over exercise stages in both rigorous and mild cooling conditions. Ratings of overall comfort were 30% higher (more positive) and more stable in mild cooling (p<0.001). The mild cooling regime was more effective than rigorous cooling in allowing the process of heat exchange to occur, thus maintaining thermal homeostasis and subjective comfort during physical exertion.

  14. In vivo maximal fascicle-shortening velocity during plantar flexion in humans.

    Science.gov (United States)

    Hauraix, Hugo; Nordez, Antoine; Guilhem, Gaël; Rabita, Giuseppe; Dorel, Sylvain

    2015-12-01

    Interindividual variability in performance of fast movements is commonly explained by a difference in maximal muscle-shortening velocity due to differences in the proportion of fast-twitch fibers. To provide a better understanding of the capacity to generate fast motion, this study aimed to 1) measure for the first time in vivo the maximal fascicle-shortening velocity of human muscle; 2) evaluate the relationship between angular velocity and fascicle-shortening velocity from low to maximal angular velocities; and 3) investigate the influence of musculo-articular features (moment arm, tendinous tissues stiffness, and muscle architecture) on maximal angular velocity. Ultrafast ultrasound images of the gastrocnemius medialis were obtained from 31 participants during maximal isokinetic and light-loaded plantar flexions. A strong linear relationship between fascicle-shortening velocity and angular velocity was reported for all subjects (mean R(2) = 0.97). The maximal shortening velocity (V(Fmax)) obtained during the no-load condition (NLc) ranged between 18.8 and 43.3 cm/s. V(Fmax) values were very close to those of the maximal shortening velocity (V(max)), which was extrapolated from the F-V curve (the Hill model). Angular velocity reached during the NLc was significantly correlated with this V(Fmax) (r = 0.57; P < 0.001). This finding was in agreement with assumptions about the role of muscle fiber type, whereas interindividual comparisons clearly support the fact that other parameters may also contribute to performance during fast movements. Nevertheless, none of the biomechanical features considered in the present study were found to be directly related to the highest angular velocity, highlighting the complexity of the upstream mechanics that lead to maximal-velocity muscle contraction.

  15. Active shortening protects against stretch-induced force deficits in human skeletal muscle.

    Science.gov (United States)

    Saripalli, Anjali L; Sugg, Kristoffer B; Mendias, Christopher L; Brooks, Susan V; Claflin, Dennis R

    2017-02-23

    Skeletal muscle contraction results from molecular interactions of myosin "crossbridges" with adjacent actin filament binding sites. The binding of myosin to actin can be "weak" or "strong", and only strong binding states contribute to force production. During active shortening, the number of strongly-bound crossbridges declines with increasing shortening velocity. Forcibly stretching a muscle that is actively shortening at high velocity results in no apparent negative consequences whereas stretch of an isometrically (fixed-length) contracting muscle causes ultrastructural damage and a decline in force-generating capability. Our working hypothesis is that stretch-induced damage is uniquely attributable to the population of crossbridges that are strongly-bound. We tested the hypothesis that stretch-induced force deficits decline as the prevailing shortening velocity is increased. Experiments were performed on permeabilized segments of individual skeletal muscle fibers obtained from human subjects. Fibers were maximally activated and either allowed to generate maximum isometric force (Fo), or to shorten at velocities that resulted in force maintenance of ≈50% Fo or ≈2% Fo. For each test condition, a rapid stretch equivalent to 0.1 x optimal fiber length was applied. Relative to pre-stretch Fo, force deficits resulting from stretches applied during force maintenance of 100%, ≈50%, and ≈2% Fo were 23.2 ± 8.6%, 7.8 ± 4.2% and 0.3 ± 3.3%, respectively (mean ± SD, n=20). We conclude that stretch-induced damage declines with increasing shortening velocity, consistent with the working hypothesis that the fraction of strongly-bound crossbridges is a causative factor in the susceptibility of skeletal muscle to stretch-induced damage.

  16. Force depression following muscle shortening in sub-maximal voluntary contractions of human adductor pollicis.

    Science.gov (United States)

    Rousanoglou, Elissavet N; Oskouei, Ali E; Herzog, Walter

    2007-01-01

    Mechanical properties of skeletal muscles are often studied for controlled, electrically induced, maximal, or supra-maximal contractions. However, many mechanical properties, such as the force-length relationship and force enhancement following active muscle stretching, are quite different for maximal and sub-maximal, or electrically induced and voluntary contractions. Force depression, the loss of force observed following active muscle shortening, has been observed and is well documented for electrically induced and maximal voluntary contractions. Since sub-maximal voluntary contractions are arguably the most important for everyday movement analysis and for biomechanical models of skeletal muscle function, it is important to study force depression properties under these conditions. Therefore, the purpose of this study was to examine force depression following sub-maximal, voluntary contractions. Sets of isometric reference and isometric-shortening-isometric test contractions at 30% of maximal voluntary effort were performed with the adductor pollicis muscle. All reference and test contractions were executed by controlling force or activation using a feedback system. Test contractions included adductor pollicis shortening over 10 degrees, 20 degrees, and 30 degrees of thumb adduction. Force depression was assessed by comparing the steady-state isometric forces (activation control) or average electromyograms (EMGs) (force control) following active muscle shortening with those obtained in the corresponding isometric reference contractions. Force was decreased by 20% and average EMG was increased by 18% in the shortening test contractions compared to the isometric reference contractions. Furthermore, force depression was increased with increasing shortening amplitudes, and the relative magnitudes of force depression were similar to those found in electrically stimulated and maximal contractions. We conclude from these results that force depression occurs in sub

  17. Crustal shortening and Eocene extension in the southeastern Canadian Cordillera: Some thermal and rheological considerations

    Science.gov (United States)

    Liu, Mian; Furlong, Kevin P.

    1993-06-01

    Metamorphic core complexes in the southeastern Canadian Cordillera were formed during Eocene crustal extension, shortly (within a few millions of years) after Late Jurassic-Paleocene crustal shortening. Thermal-rheological modeling, constrained by geological and geochronological studies of the Valhalla core complex and other core complexes in this region, is used to investigate two major problems concerning the formation of these core complexes: (1) the dynamic links between crustal shortening and extension and (2) the cooling history and unroofing rates during extension. Thermal-rheological effects associated with crustal shortening are integrated through the history of crustal compression, since crustal shortening in this region was a long and slow process and cannot be treated as an instantaneous event. Our results suggest that crustal shortening may have played an important role in Eocene extension in the southeastern Canadian Cordillera by (1) producing a thickened and therefore unstable crust and (2) thermally weakening the lithosphere. However, heat generated by crustal shortening is not enough to account for the thermal state of the Valhalla complex, and additional heat sources at depth may be necessary. We then investigate thermal evolution during extension in both a simple shear model and a progressive pure stretching model. We show that the geotherm in an extensional region is time-and space-dependent and is affected by many variables including the preextensional thermal history and the mode of extension. Thus caution needs to be exercised when inferring unroofing rates from thermochronologic data. The cooling history of the Valhalla core complex may be explained by unroofing at rates of 1-2 mm/yr.

  18. Edentulism and shortened dental arch in Brazilian elderly from the National Survey of Oral Health 2003

    Directory of Open Access Journals (Sweden)

    Marco Túlio Freitas Ribeiro

    2011-10-01

    Full Text Available OBJECTIVE: To describe the distribution of edentulism and estimate the prevalence of functional dentition and shortened dental arch among elderly population. METHODS: A population-based epidemiological study was carried out with a sample of 5,349 respondents aged 65 to 74 years obtained from the 2002 and 2003 Brazilian Ministry of Health/Division of Oral Health survey database. The following variables were studied: gender; macroregion of residence; missing teeth; percentage that met the World Health Organization goal for oral health in the age group 65 to 74 years (50% having at least 20 natural teeth; presence of shortened dental arch; number of posterior occluding pairs of teeth. The Chi-square test assessed the association between categorical variables. The Kruskal-Wallis and Mann-Whitney tests were used to assess differences of mean between number of posterior occluding pairs teeth, macro-region and gender. RESULTS: The elderly population had an average of 5.49 teeth (SD: 7.93 with a median of 0. The proportion of completely edentulous respondents was 54.7%. Complete edentulism was 18.2% in the upper arch and 1.9% in the lower arch. The World Health Organization goal was achieved in 10% of all respondents studied. However, only 2.7% had acceptable masticatory function and aesthetics (having at least shortened dental arch and a mean number of posterior occluding pairs of 6.94 (SD=2.97. There were significant differences of the percentage of respondents that met the World Health Organization goal and presence of shortened dental arch between men and women. There were differences in shortened dental arch between macroregions. CONCLUSIONS: The Brazilian epidemiological oral health survey showed high rate of edentulism and low rate of shortened dental arch in the elderly population studied, thus suggesting significant functional and aesthetic impairment in all Brazilian macroregions especially among women.

  19. Shortening behavior of the different components of muscle-tendon unit during isokinetic plantar flexions.

    Science.gov (United States)

    Hauraix, Hugo; Nordez, Antoine; Dorel, Sylvain

    2013-10-01

    The torque-velocity relationship has been widely considered as reflecting the mechanical properties of the contractile apparatus, and the influence of tendinous tissues on this relationship obtained during in vivo experiments remains to be determined. This study describes the pattern of shortening of various muscle-tendon unit elements of the triceps surae at different constant angular velocities and quantifies the contributions of fascicles, tendon, and aponeurosis to the global muscle-tendon unit shortening. Ten subjects performed isokinetic plantar flexions at different preset angular velocities (i.e., 30, 90, 150, 210, 270, and 330°/s). Ultrafast ultrasound measurements were performed on the muscle belly and on the myotendinous junction of the medial and lateral gastrocnemius muscles. The contributions of fascicles, tendon, and aponeurosis to global muscle-tendon unit shortening velocity were calculated for velocity conditions for four parts of the total range of motion. For both muscles, the fascicles' contribution decreased throughout the motion (73.5 ± 21.5% for 100-90° angular range to 33.7 ± 20.2% for 80-70°), whereas the tendon contribution increased (25.8 ± 15.4 to 55.6 ± 16.8%). In conclusion, the tendon contribution to the global muscle-tendon unit shortening is significant even during a concentric contraction. However, this contribution depends on the range of motion analyzed. The intersubject variability found in the maximal fascicle shortening velocity, for a given angular velocity, suggests that some subjects might possess a more efficient musculoarticular complex to produce the movement velocity. These findings are of great interest for understanding the ability of muscle-tendon shortening velocity.

  20. Superimposed folding and thrusting by two phases of mutually orthogonal or oblique shortening in analogue models

    Science.gov (United States)

    Deng, Hongling; Koyi, Hemin A.; Nilfouroushan, Faramarz

    2016-02-01

    Orogens may suffer more than one phase shortening resulting in superposition of structures of different generations. Superimposition of orthogonal or oblique shortening is studied using sandbox and centrifuge modelling. Results of sand models show that in orthogonal superimposition, the two resulting structural trends are approximately orthogonal to each other. In oblique superimposition, structures trend obliquely to each other in the relatively thin areas of the model (foreland), and mutually orthogonal in areas where the model is thickened during the first phase of shortening (i.e. the hinterland). Thrusts formed during the first shortening phase may be reactivated during the later shortening phase. Spacing of the later phase structures is not as wide as expected, considering they across the pre-existing thickened wedge. Superposition of structures results in formation of type 1 fold interference pattern. Bedding is curved outwards both in the dome and basin structures. Folded layers are dipping and plunging outwards in a dome, while they are dipping and plunging inwards in a basin. In the areas between two adjacent domes or basins (i.e. where an anticline is superimposed by a syncline or a syncline is superimposed by an anticline), bedding is curved inwards, and the anticlines plunge inwards and the synclines outwards. The latter feature could be helpful to determine the age relationship for type 2 fold interference pattern. In tectonic regions where multiple phases of shortening have occurred, the orogenic-scale dome-and-basin and arrowhead-shaped interference patterns are commonly formed, as in the models. However, in some areas, the fold interference pattern might be modified by a later phase of thrusting. Similar to models results, superimposition of two and/or even more deformation phases may not be recorded by structures all over the tectonic area.

  1. Very strict selectional restrictions

    CERN Document Server

    Laporte, Eric; Dias, Maria Carmelita P

    2007-01-01

    We discuss the characteristics and behaviour of two parallel classes of verbs in two Romance languages, French and Portuguese. Examples of these verbs are Port. abater [gado] and Fr. abattre [b\\'etail], both meaning "slaughter [cattle]". In both languages, the definition of the class of verbs includes several features: - They have only one essential complement, which is a direct object. - The nominal distribution of the complement is very limited, i.e., few nouns can be selected as head nouns of the complement. However, this selection is not restricted to a single noun, as would be the case for verbal idioms such as Fr. monter la garde "mount guard". - We excluded from the class constructions which are reductions of more complex constructions, e.g. Port. afinar [instrumento] com "tune [instrument] with".

  2. Caloric stimulation

    Science.gov (United States)

    ... back and forth during nystagmus. You may have vertigo , and sometimes, you can also have nausea. This ... used to find the cause of: Dizziness or vertigo Hearing loss that may be due to certain ...

  3. Distal femoral shortening in total hip arthroplasty for complex primary hip reconstruction. A new surgical technique.

    Science.gov (United States)

    Koulouvaris, Panagiotis; Stafylas, Kosmas; Sculco, Thomas; Xenakis, Theodore

    2008-10-01

    Successful total hip arthroplasty (THA) in congenital dislocated hips demands anatomical reduction in the normal center of rotation without overstretching the sciatic nerve and without excessive compression or abnormal forces across the joint. Proximal femoral and subtrochanteric shortening osteotomy has been described for THA for the treatment of dislocated hips. However, these osteotomies are demanding, associated with deformation of femoral canal and nonunion, and may increase the femoral stem stress. This study reports excellent results in 24 patients with a new surgical technique that combines THA with a distal femoral shortening in severely deformed hips using customized components.

  4. Energy cost of isometric force production after active shortening in skinned muscle fibres.

    Science.gov (United States)

    Joumaa, V; Fitzowich, A; Herzog, W

    2017-02-23

    The steady state isometric force after active shortening of a skeletal muscle is lower than the purely isometric force at the corresponding length. This property of skeletal muscle is known as force depression. The purpose of this study was to investigate whether the energy cost of force production at the steady state after active shortening was reduced compared to the energy cost of force production for a purely isometric contraction performed at the corresponding length (same length, same activation). Experiments were performed in skinned fibres isolated from rabbit psoas muscle. Skinned fibres were actively shortened from an average sarcomere length of 3.0 µm to an average sarcomere length of 2.4 µm. Purely isometric reference contractions were performed at an average sarcomere length of 2.4 µm. Simultaneously with the force measurements, the ATP cost was measured during the last 30 seconds of isometric contractions using an enzyme-coupled assay. Stiffness was calculated during a quick stretch-release cycle of 0.2% fibre length performed once the steady state had been reached after active shortening and during the purely isometric reference contractions. Force and stiffness following active shortening were decreased by 10.0±1.8% and 11.0±2.2%, respectively compared to the isometric reference contractions. Similarly, ATPase activity per second (not normalized to the force) showed a decrease of 15.6±3.0% in the force depressed state compared to the purely isometric reference state. However, ATPase activity per second per unit of force was similar for the isometric contractions following active shortening (28.7±2.4 mM/mN.s.mm(3)) and the corresponding purely isometric reference contraction (30.9±2.8 mM/mN.s.mm(3)). Furthermore, the reduction in absolute ATPase activity per second was significantly correlated with force depression and stiffness depression. These results are in accordance with the idea that force depression following active shortening is

  5. Markers of cellular senescence. Telomere shortening as a marker of cellular senescence.

    Science.gov (United States)

    Bernadotte, Alexandra; Mikhelson, Victor M; Spivak, Irina M

    2016-01-01

    The cellular senescence definition comes to the fact of cells irreversible proliferation disability. Besides the cell cycle arrest, senescent cells go through some morphological, biochemical, and functional changes which are the signs of cellular senescence. The senescent cells (including replicative senescence and stress-induced premature senescence) of all the tissues look alike. They are metabolically active and possess the set of characteristics in vitro and in vivo, which are known as biomarkers of aging and cellular senescence. Among biomarkers of cellular senescence telomere shortening is a rather elegant frequently used biomarker. Validity of telomere shortening as a marker for cellular senescence is based on theoretical and experimental data.

  6. Telomere shortening correlates to dysplasia but not to DNA aneuploidy in longstanding ulcerative colitis

    DEFF Research Database (Denmark)

    Friis-Ottessen, Mariann; Bendix, Laila; Kølvraa, Steen;

    2014-01-01

    Ulcerative colitis (UC) is a chronic, inflammatory bowel disease which may lead to dysplasia and adenocarcinoma in patients when long-lasting. Short telomeres have been reported in mucosal cells of UC patients. Telomeres are repetitive base sequences capping the ends of linear chromosomes......, and protect them from erosion and subsequent wrongful recombination and end-to-end joining during cell division. Short telomeres are associated with the development of chromosomal instability and aneuploidy, the latter being risk factors for development of dysplasia and cancer. Specifically, the abrupt...... shortening of one or more telomeres to a critical length, rather than bulk shortening of telomeres, seems to be associated with chromosomal instability....

  7. Síntesis rigurosa de redes de intercambiadores de calor usando un método híbrido

    OpenAIRE

    J. M. García Hernández; J. M. Ponce Ortega; M. Serna González

    2007-01-01

    En este artículo se presenta un método híbrido para la síntesis de redes de intercambio de calor que incluye el diseño detallado de los intercambiadores de calor. Para realizar esta tarea se combinan las reglas heurísticas del análisis de pliegue con una técnica de programación matemática, junto con un algoritmo de optimización de intercambiadores de calor de coraza y tubos basado en el método riguroso Bell-Delaware. De esta manera, las caídas de presión de las corrientes son tratadas como va...

  8. Shortening filtrations

    Institute of Scientific and Technical Information of China (English)

    ENOCHS Edgar E.

    2012-01-01

    Let C be a set of modules.We argue that there is an ordinal κ such that if a module has a filtration by modules in C,then it has a filtration of length κ by direct sums of modules in C.As an application we give another way to prove a result of Saorín and (S)(t)oví(c)ek and of (S)(t)oví(c)ek.

  9. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    Directory of Open Access Journals (Sweden)

    Yoalbys Retirado-Mediaceja

    2011-03-01

    Full Text Available En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinámicas que influyen en la transferencia de calor por convección y radiación durante el secado y se calcularon, además, los criterios adimensionales para determinar el tipo predominante de convección. Se comprobó que durante el secado solar a la intemperie predomina la convección y que en las condiciones de experimentación analizadas la radiación tuvo una incidencia secundaria. Los resultados evidenciaron que el calor se transfiere por convección libre, forzada y mixta, predominando la forzada, para la cual los coeficientes de transferencia de calor mínimos y máximos mostraron pequeñas variaciones entre ambas pilas. Los flujos de calor por convección promedios fueron 978,74 y 1 156,58 W/m2 , mientras que los flujos por radiación ascendieron a 324,71 y 355,36 W/m2 para las pilas #1 y #2, respectivamente.

  10. [Carbohydrate restriction in the larval diet causes oxidative stress in adult insects of Drosophila melanogaster].

    Science.gov (United States)

    Rovenko, B M; Lushchak, V I; Lushchak, O V

    2013-01-01

    The influence of 20 and 1% glucose and fructose, which were components of larval diet, on the level of oxidized proteins and lipids, low molecular mass antioxidant content as well as activities of antioxidant and associated enzymes in adult fruit fly Drosophila melanogaster were investigated. The restriction of carbohydrates in larval diet leads to oxidative stress in adult insects. It is supported by 40-50% increased content of protein carbonyl groups and by 60-70% decreased level of protein thiol groups as well as by a 4-fold increase of lipid peroxide content in 2-day-old flies of both sexes, developed on the diet with 1% carbohydrates. Oxidative stress, induced by carbohydrate restriction of the larval diet, caused the activation of antioxidant defence, differently exhibited in male and female fruit flies. Caloric restriction increased activity of superoxide dismutase and thioredoxin reductase associating only in males with 2-fold higher activity of NADPH-producing enzymes--glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase. Carbohydrate restriction in the larval diet caused the increase of uric acid content, but the decrease in catalase activity in males. In females the values of these parameters were changed in opposite direction compared with males. The obtained results let us conclude the different involvement of low molecular mass antioxidants, glutathione and uric acid, and antioxidant enzyme catalase in the protection of male and female fruit fly macromolecules against oxidative damages, caused by calorie restriction of larval diet.

  11. Beneficial effects of mild stress (hormetic effects): dietary restriction and health.

    Science.gov (United States)

    Kouda, Katsuyasu; Iki, Masayuki

    2010-01-01

    Hormesis is defined as a dose-response phenomenon characterized by low-dose stimulation and high-dose inhibition, and has been recognized as representing an overcompensation for mild environmental stress. The beneficial effects of mild stress on aging and longevity have been studied for many years. In experimental animals, mild dietary stress (dietary restriction, DR) without malnutrition delays most age-related physiological changes, and extends maximum and average lifespan. Animal studies have also demonstrated that DR can prevent or lessen the severity of cancer, stroke, coronary heart disease, autoimmune disease, allergy, Parkinson's disease and Alzheimer's disease. The effects of DR are considered to result from hormetic mechanisms. These effects were reported by means of various DR regimens, such as caloric restriction, total-nutrient restriction, alternate-day fasting, and short-term fasting. Mild dietary stress, including restriction of amount or frequency of intake, is the essence of DR. For more than 99% of their history, humans lived as hunter-gatherers and adapted to restrictions in their food supply. On the other hand, an oversufficiency of food for many today has resulted in the current global epidemic of obesity and obesity-related diseases. DR may be used, therefore, as a novel approach for therapeutic intervention in several diseases, when detailed information about effects of mild dietary stress on human health is obtained from clinical trials.

  12. Intermittent versus daily calorie restriction: which diet regimen is more effective for weight loss?

    Science.gov (United States)

    Varady, K A

    2011-07-01

    Dietary restriction is an effective strategy for weight loss in obese individuals. The most common form of dietary restriction implemented is daily calorie restriction (CR), which involves reducing energy by 15-60% of usual caloric intake every day. Another form of dietary restriction employed is intermittent CR, which involves 24 h of ad libitum food consumption alternated with 24 h of complete or partial food restriction. Although both diets are effective for weight loss, it remains unknown whether one of these interventions produces superior changes in body weight and body composition when compared to the other. Accordingly, this review examines the effects of daily CR versus intermittent CR on weight loss, fat mass loss and lean mass retention in overweight and obese adults. Results reveal similar weight loss and fat mass loss with 3 to 12 weeks' intermittent CR (4-8%, 11-16%, respectively) and daily CR (5-8%, 10-20%, respectively). In contrast, less fat free mass was lost in response to intermittent CR versus daily CR. These findings suggest that these diets are equally as effective in decreasing body weight and fat mass, although intermittent CR may be more effective for the retention of lean mass.

  13. Caloric vestibular stimulation as a treatment for conversion disorder: A case report and medical hypothesis

    Directory of Open Access Journals (Sweden)

    Michael eNoll-Hussong

    2014-06-01

    Full Text Available Conversion disorder is a medical condition in which a person has paralysis, blindness, or other neurological symptoms that cannot be clearly explained physiologically. To date, there is neither specific nor conclusive treatment. In this paper, we draw together a number of disparate pieces of knowledge to propose a novel intervention to provide transient alleviation for this condition. As caloric vestibular stimulation (CVS has been demonstrated to modulate transiently a variety of cognitive functions associated with brain activations, especially in the temporal-parietal cortex, anterior cingulate cortex, and insular cortex, there is evidence to assume an effect in specific mental disorders. Therefore, we go on to hypothesize that lateralized cold vestibular caloric stimulation will be effective in treating conversion disorder and we present provisional evidence from one patient that supports this conclusion. If our hypothesis is correct, this will be the first time in psychiatry and neurology that a clinically well-known mental disorder, long considered difficult to understand and to treat, is relieved by a simple or common, non-invasive medical procedure.

  14. Spatio-temporal pattern of vestibular information processing after brief caloric stimulation

    Energy Technology Data Exchange (ETDEWEB)

    Marcelli, Vincenzo [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Esposito, Fabrizio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands)], E-mail: fabrizio.esposito@unina.it; Aragri, Adriana [Department of Neurological Sciences, Second University of Naples, Naples (Italy); Furia, Teresa; Riccardi, Pasquale [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Tosetti, Michela; Biagi, Laura [I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Marciano, Elio [Department of Neuroscience, University of Naples ' Federico II' , Naples (Italy); Di Salle, Francesco [Department of Cognitive Neurosciences, University of Maastricht, Maastricht (Netherlands); I.R.C.S.S. ' Stella Maris' , Pisa (Italy); Department of Neurosciences, University of Pisa, Pisa (Italy)

    2009-05-15

    Processing of vestibular information at the cortical and subcortical level is essential for head and body orientation in space and self-motion perception, but little is known about the neural dynamics of the brain regions of the vestibular system involved in this task. Neuroimaging studies using both galvanic and caloric stimulation have shown that several distinct cortical and subcortical structures can be activated during vestibular information processing. The insular cortex has been often targeted and presented as the central hub of the vestibular cortical system. Since very short pulses of cold water ear irrigation can generate a strong and prolonged vestibular response and a nystagmus, we explored the effects of this type of caloric stimulation for assessing the blood-oxygen-level-dependent (BOLD) dynamics of neural vestibular processing in a whole-brain event-related functional magnetic resonance imaging (fMRI) experiment. We evaluated the spatial layout and the temporal dynamics of the activated cortical and subcortical regions in time-locking with the instant of injection and were able to extract a robust pattern of neural activity involving the contra-lateral insular cortex, the thalamus, the brainstem and the cerebellum. No significant correlation with the temporal envelope of the nystagmus was found. The temporal analysis of the activation profiles highlighted a significantly longer duration of the evoked BOLD activity in the brainstem compared to the insular cortex suggesting a functional de-coupling between cortical and subcortical activity during the vestibular response.

  15. Remission of anosognosia for right hemiplegia and neglect after caloric vestibular stimulation.

    Science.gov (United States)

    Ronchi, Roberta; Rode, Gilles; Cotton, François; Farnè, Alessandro; Rossetti, Yves; Jacquin-Courtois, Sophie

    2013-01-01

    Neglect and related phenomena, as anosognosia for hemiplegia and somatoparaphrenia, are often associated to right-hemisphere lesions. These deficits can be alleviated by caloric vestibular stimulation, but little is known about the efficacy of this physiological intervention on neglect following left-hemisphere lesions. Here we report the case of an ambidextrous left brain-damaged patient with severe right personal and extrapersonal neglect, anosognosia for right hemiplegia and somatoparaphrenia. These symptoms co-occurred with more typical manifestations of left-brain damage, such as aphasia and apraxia. Neurological examination revealed right hemiplegia, hemianesthesia and hemianopia. Visuo-spatial tests for personal and extrapersonal neglect, as well as an anosognosia questionnaire, were submitted before and after caloric vestibular stimulation. Results showed a dramatic improvement of anosognosia for hemiplegia and neglect; no change was observed for the remaining deficits. The results confirm the notion of the selectivity of vestibular stimulation for neglect and related disorders and extend this notion by showing that similar effects can be obtained after lesion of the left hemisphere, suggesting that similar mechanisms are responsible for left- and right-sided neglect. Such a peculiar association of language and visuo-spatial disorders jointly present after a left-sided lesion opens the question of the link between handedness and lateralization of cognitive functions.

  16. Coeficientes de transferencia de calor en enfriadores de mineral laterítico a escala piloto

    Directory of Open Access Journals (Sweden)

    Ángel Legrá-Legrá

    2009-03-01

    Full Text Available En la Planta de Hornos de Reducción de la empresa niquelera Ernesto Guevara las elevadas temperaturas del mineral reducido a la salida de los enfriadores (coolers afectan el desarrollo eficiente del proceso de lixiviación. Se realizó una investigación, a escala piloto, en los enfriadores de mineral reducido con el fin de evaluar el comportamiento de los parámetros de transferencia de calor que caracterizan el proceso; para ello se registraron los valores de temperatura del agua y del flujo y la temperatura del mineral, tanto a la entrada como a la salida de la instalación, para valores de flujos de 10 y 19 l/min. Como resultado se obtuvo el procedimiento de cálculo para determinar los coeficientes superficiales de transferencia de calor por unidad de longitud. Se encontró que en los enfriadores de mineral reducido predominan la conducción y radiación del mineral a la pared interior del cilindro cubierta por el sólido así como la convección y evaporación del agua al medio que permite dirigir las acciones hacia estos elementos para aumentar la eficiencia de la instalación.

  17. Transferencia de calor en la colada continua de aceros. I parte. El molde

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-10-01

    Full Text Available The continuous casting mold plays the important role of receiving the liquid steel and allowing an uniform and defect free solidified skin to be developed. In this work, the different heat transfer mechanisms which are present from the liquid steel to the mold cooling water are reviewed. The effect of operating variables on heat extraction and the relationship between global and distributed heat flux are also analyzed.

    El molde de colada continua cumple la importante función de recibir el acero líquido y permitir que se desarrolle una capa solidificada uniforme y libre de defectos. En este trabajo se revisan los distintos mecanismos implicados en el proceso de transferencia de calor, desde el acero líquido hasta el agua de refrigeración del molde. Se analiza también el efecto de las distintas variables de funcionamiento en la extracción calórica producida y la relación entre el flujo global de calor y su distribución a lo largo del molde.

  18. Conceptos esenciales de la transmisión de calor en una edificación

    Directory of Open Access Journals (Sweden)

    Safranez, Carlos

    1981-05-01

    Full Text Available Dirigiéndose esta publicación al técnico del ramo de la Construcción, poco familiarizado con los problemas de aislamiento térmico, se presenta una breve exposición de los conceptos esenciales de la transmisión de calor en una edificación. Se exponen ejemplos del cálculo de la resistencia térmica y de la curva de temperatura de una cubierta plana y de un sótano. Se analiza la repercusión del aislamiento térmico sobre el consumo de energía con tiempo frío y tiempo caluroso. Sobre la posibilidad de producirse condensaciones, y sobre la temperatura a que estará expuesta la membrana impermeabilizante de un sótano, debido a la calefacción, con el fin de que no sobrepase los límites fijados. Finalmente, se dan a conocer dos ábacos para la determinación del coeficiente K de la transmisión de calor y de la resistencia térmica R, de distintos tipos de aislamiento.

  19. Influencia del contexto hidrogeológico en la eficiencia de los sistemas cerrados de bomba de calor

    OpenAIRE

    Folch Sancho, Albert; Goma Roca, Albert; Jimenez Parras, Santos; Zarroca HErnandez, Mario; Bach Plaza, Joan; Mas Pla, Josep

    2013-01-01

    Los sistemas geotérmicos de bomba de calor se caracterizan por presentar una elevada eficiencia energética en condiciones de óptimo funcionamiento. Aun así, su productividad se ve condicionada por las características geológicas e hidrogeológicas del medio. El presente estudio centra su interés en los sistemas cerrados verticales, dado que en muchos casos no se contabiliza el efecto del flujo de agua subterránea de forma adecuada. En este trabajo se evalúa el transporte de calor en 4 contextos...

  20. Transferencia de calor en el secado solar a la intemperie de menas lateríticas ferroniquelíferas

    OpenAIRE

    Yoalbys Retirado-Mediaceja; Marbelis Lamorú-Urgelles; Ever Góngora-Leyva; Enrique Torres-Tamayo; Benigno Leyva-de la Cruz; Daynelis García-Batista

    2011-01-01

    En Moa, las menas lateríticas son sometidas a secado solar a la intemperie para reducirles el contenido de humedad antes de incorporarlas al proceso de secado térmico convencional. Este artículo evalúa los procesos de transferencia de calor fundamentales que tienen lugar durante el secado natural con el propósito de determinar el modo predominante de transferencia de calor. En dos pilas de menas lateríticas expuestas a secado solar natural se midieron las variables climatológicas y termodinám...

  1. Caloric Intake from Fast Food among Children and Adolescents in the United States, 2011-2012. NCHS Data Brief. Number 213

    Science.gov (United States)

    Vikraman, Sundeep; Fryar, Cheryl D.; Ogden, Cynthia L.

    2015-01-01

    Consumption of fast food has been linked to weight gain in adults. Fast food has also been associated with higher caloric intake and poorer diet quality in children and adolescents. From 1994 through 2006, caloric intake from fast food increased from 10% to 13% among children aged 2-18 years. This report presents the most recent data on the…

  2. Phenotypic Stability of Energy Balance Responses to Experimental Total Sleep Deprivation and Sleep Restriction in Healthy Adults

    Directory of Open Access Journals (Sweden)

    Laura E. Dennis

    2016-12-01

    Full Text Available Experimental studies have shown that sleep restriction (SR and total sleep deprivation (TSD produce increased caloric intake, greater fat consumption, and increased late-night eating. However, whether individuals show similar energy intake responses to both SR and TSD remains unknown. A total of N = 66 healthy adults (aged 21–50 years, 48.5% women, 72.7% African American participated in a within-subjects laboratory protocol to compare daily and late-night intake between one night of SR (4 h time in bed, 04:00–08:00 and one night of TSD (0 h time in bed conditions. We also examined intake responses during subsequent recovery from SR or TSD and investigated gender differences. Caloric and macronutrient intake during the day following SR and TSD were moderately to substantially consistent within individuals (Intraclass Correlation Coefficients: 0.34–0.75. During the late-night period of SR (22:00–04:00 and TSD (22:00–06:00, such consistency was slight to moderate, and participants consumed a greater percentage of calories from protein (p = 0.01 and saturated fat (p = 0.02 during SR, despite comparable caloric intake (p = 0.12. Similarly, participants consumed a greater percentage of calories from saturated fat during the day following SR than TSD (p = 0.03. Participants also consumed a greater percentage of calories from protein during recovery after TSD (p < 0.001. Caloric intake was greater in men during late-night hours and the day following sleep loss. This is the first evidence of phenotypic trait-like stability and differential vulnerability of energy balance responses to two commonly experienced types of sleep loss: our findings open the door for biomarker discovery and countermeasure development to predict and mitigate this critical health-related vulnerability.

  3. Hypothalamic neuropeptide gene expression during recovery from food restriction superimposed on short-day photoperiod-induced weight loss in the Siberian hamster.

    Science.gov (United States)

    Archer, Zoë A; Moar, Kim M; Logie, Tracy J; Reilly, Laura; Stevens, Valerie; Morgan, Peter J; Mercer, Julian G

    2007-09-01

    Previously, 40% food restriction of male Siberian hamsters over 21 days in short-day (SD) photoperiod induced characteristic changes in expression of hypothalamic arcuate nucleus energy balance genes; mRNAs for neuropeptide Y, agouti-related peptide, and leptin receptor were upregulated, and those of proopiomelanocortin and cocaine- and amphetamine-regulated transcript were depressed. The present study examined the effect of refeeding hamsters for 6 days (approximately 50% recovery of weight differential) or 19 days (resumption of appropriate weight trajectory). Hyperphagia continued throughout refeeding, but differences in fat pad weights and leptin levels had disappeared after 19 days. Cocaine- and amphetamine-regulated transcript gene expression was depressed by prior restriction in both refed groups. The depressive effect of prior restriction on proopiomelanocortin gene expression had disappeared after 19 days of refeeding. There was no effect of prior food restriction on neuropeptide Y or agouti-related peptide gene expression. Expression of the anorexigenic brain-derived neurotrophic factor was downregulated in the ventromedial nucleus after SD exposure for 12 wk. In the SD food restriction study, there were effects of photoperiod on brain-derived neurotrophic factor gene expression but not of prior food restriction. Hypothalamic energy balance genes in the hamster respond asynchronously to return to a seasonally appropriate body weight. The achievement of this weight rather than the weight at which caloric restriction was imposed is the critical factor. The differential responses of hypothalamic energy balance genes to food restriction and refeeding are poorly characterized in any species, a critical issue given their potential relevance to human weight loss strategies that involve caloric restriction.

  4. Recovery time of motor evoked potentials following lengthening and shortening muscle action in the tibialis anterior

    NARCIS (Netherlands)

    Tallent, J.; Goodall, S.; Hortobagyi, T.; Gibson, A. St Clair; French, D. N.; Howatson, G.

    2012-01-01

    Motor evoked potentials (MEP) at rest remain facilitated following an isometric muscle contraction. Because the pre-synaptic and post-synaptic control of shortening (SHO) and lengthening (LEN) contractions differs, the possibility exists that the recovery of the MEP is also task specific. The time c

  5. Regional myocardial shortening in relation to graft-reactive hyperemia and flow after coronary bypass surgery

    NARCIS (Netherlands)

    R.W. Brower (Ronald); P.W.J.C. Serruys (Patrick); E. Bos (Egbert); J. Nauta (Jan)

    1979-01-01

    textabstractExtent of regional shortening of myocardium in areas newly perfused by bypass grafting was determined in 56 patients by a new technique employing four to six radiopaque markers sutured in pairs to the epicardium near the coronary anastomosis. Paradoxical systolic expansion (PSE) was mani

  6. Stochastic modeling of length-dependent telomere shortening in Corvus monedula

    NARCIS (Netherlands)

    Grasman, J.; Salomons, H. M.; Verhulst, S.

    2011-01-01

    It was recently shown that, within individuals, longer telomeres shorten at a higher rate. This explorative study deals with a mathematical model of this process. It is a nonlinear differential equation describing length-dependent decrease that can be linked to a Poisson process. The model also take

  7. Stochastic modelling of length-dependent telomere shortening in Corvus monedula

    NARCIS (Netherlands)

    Grasman, J.; Salomons, H.M.; Verhulst, S.

    2011-01-01

    It was recently shown that, within individuals, longer telomeres shorten at a higher rate. This explorative study deals with a mathematical model of this process. It is a nonlinear differential equation describing length-dependent decrease that can be linked to a Poisson process. The model also take

  8. Crossbridge and non-crossbridge contributions to force in shortening and lengthening muscle.

    Science.gov (United States)

    Ranatunga, K W; Roots, H; Pinniger, G J; Offer, G W

    2010-01-01

    Analysis of tension responses to ramp length changes in muscle can provide important information about the crossbridge cycle. During a ramp length change, the force response of an active muscle shows an early change in slope (the P₁ transition) followed by a later, gradual change in slope (the P₂ transition). Modeling shows that the first transition reflects the tension change associated with the crossbridge power stroke in shortening and with its reversal in lengthening; the reduction in slope at the second transition occurs when most of the crossbridges (myosin heads) that were attached at the start of the ramp become detached; the steady tension during shortening is borne mainly by post-stroke heads whereas tension during lengthening is borne mostly by pre-stroke heads. After the P₂ transition, the tension reaches a steady level in the model whereas in the experiments the tension continues to increase during lengthening or to decrease during shortening; this tension change is seen at a wide range of sarcomere lengths and even when active force is reduced by a myosin inhibitor. It appears that some non-crossbridge components in muscle fibers stiffen upon activation and contribute to the continued tension rise during lengthening; release of such tension leads to tension decline during shortening. Thus, non-crossbridge visco-elasticity in sarcomeres may also contribute to energy storage and release during in situ muscle function.

  9. Fiber type composition and maximum shortening velocity of muscles crossing the human shoulder.

    Science.gov (United States)

    Srinivasan, R C; Lungren, M P; Langenderfer, J E; Hughes, R E

    2007-03-01

    A study of the fiber type composition of fourteen muscles spanning the human glenohumeral joint was carried out with the purpose of determining the contribution of fiber types to overall muscle cross-sectional area (CSA) and to estimate the maximum shortening velocity (V(max)) of those muscles. Muscle biopsies were procured from 4 male cadavers (mean age 50) within 24 hr of death, snap frozen, mounted, and transversely sectioned (10 microm). Slides were stained for myofibrillar ATPase after alkaline preincubation. Photoimages were taken of defined areas (100 fibers) using the Bioquant system, and fiber type and CSA were measured from these images. Staining for mATPase produced three different fiber types: slow-oxidative (SO), fast-oxidative-glycolytic (FOG), and fast-glycolytic (FG). On average, the muscle fiber type composition ranged from 22 to 40% of FG, from 17 to 51% of FOG, and from 23 to 56% of SO. Twelve out of the 14 muscles had average SO proportions ranging from 35 to 50%. V(max) was calculated from the fiber type contribution relative to CSA and shortening velocity values taken from the literature. The maximum velocities of shortening presented here provide a physiological basis for the development of human shoulder musculoskeletal models suitable for predicting muscle forces for functionally relevant tasks encompassing conditions of muscle shortening and lengthening.

  10. The effect of hypoxia on shortening contractions in rat diaphragm muscle.

    NARCIS (Netherlands)

    Machiels, H.A.; Heijden, E. van der; Heunks, L.M.A.; Dekhuijzen, P.N.R.

    2001-01-01

    Hypoxia is known to reduce isometric contractile properties of isolated rat diaphragm bundles. Its effect on isotonic contractile properties (i.e. force-velocity relationship and power output) has not been studied. We hypothesized that hypoxia reduces velocity of shortening and consequently power ou

  11. The Shortened Visuospatial Questionnaire for Children: A Useful Tool to Identify Students with Low Visuospatial Abilities

    Science.gov (United States)

    Fastame, Maria Chiara; Cherchi, Rossella; Penna, Maria Pietronilla

    2015-01-01

    The current research was aimed mainly at exploring the reliability of a short-screening tool developed to self-evaluate visuospatial abilities in children. We presented 290 Italian third, fourth, and fifth graders with the 16-item Shortened Visuospatial questionnaire and several objective measures of intellectual efficiency, such as Raven's…

  12. Decayed/missing/filled teeth and shortened dental arches in Tanzanian adults.

    NARCIS (Netherlands)

    Sarita, P.T.N.; Witter, D.J.; Kreulen, C.M.; Matee, M.I.N.; Hof, M.A. van 't; Creugers, N.H.J.

    2004-01-01

    PURPOSE: This study assessed decayed/missing/filled teeth (DMFT), presence of occlusal units, and prevalence of shortened dental arches in a Tanzanian adult population. MATERIALS AND METHODS: The dental state of samples of the Tanzanian population was studied. Oral examinations were conducted on 5,5

  13. Contribution of NHE-1 to cell length cardiac shortening of normal and failing rabbit myocytes

    NARCIS (Netherlands)

    M.M.G.J. van Borren; J.G. Zegers; A. Baartscheer; J.H. Ravesloot

    2006-01-01

    At the same intracellular pH (pH(i)) Na+/H+ exchange (NHE-1) fluxes of ventricular myocytes of hypertrophied failing hearts (HFH) are increased. We assessed how NHE-1 affected cell length shortening. pH(i) was measured fluorimetrically in resting and twitching (1 - 3 Hz)normal and HFH rabbit myocyte

  14. Changing Quality Controls: The Effects of Increasing Product Variety and Shortening Product Life Cycles

    NARCIS (Netherlands)

    J.D. van Iwaarden (Jos)

    2006-01-01

    textabstractIn many industries (e.g. cars, electronics, clothing) manufacturing complexity and unpredictability have increased in recent years because of increasing product variety and shortening product life cycles. At the same time, manufacturers in these industries appear to have more problems wi

  15. Common Patterns of Congenital Lower Extremity Shortening: Diagnosis, Classification, and Follow-up.

    Science.gov (United States)

    Bedoya, Maria A; Chauvin, Nancy A; Jaramillo, Diego; Davidson, Richard; Horn, B David; Ho-Fung, Victor

    2015-01-01

    Congenital lower limb shortening is a group of relatively rare, heterogeneous disorders. Proximal focal femoral deficiency (PFFD) and fibular hemimelia (FH) are the most common pathologic entities in this disease spectrum. PFFD is characterized by variable degrees of shortening or absence of the femoral head, with associated dysplasia of the acetabulum and femoral shaft. FH ranges from mild hypoplasia to complete absence of the fibula with variable shortening of the tibia. The development of the lower limb requires complex and precise gene interactions. Although the etiologies of PFFD and FH remain unknown, there is a strong association between the two disorders. Associated congenital defects in the lower extremity are found in more than 50% of patients with PFFD, ipsilateral FH being the most common. FH also has a strong association with shortening and bowing of the tibia and with foot deformities such as absence of the lateral rays of the foot. Early diagnosis and radiologic classification of these abnormalities are imperative for appropriate management and surgical planning. Plain radiography remains the main diagnostic imaging modality for both PFFD and FH, and appropriate description of the osseous abnormalities seen on radiographs allows accurate classification, prognostic evaluation, and surgical planning. Minor malformations may commonly be misdiagnosed.

  16. The addition of lidocaine to bupivacaine does not shorten the duration of spinal anesthesia

    DEFF Research Database (Denmark)

    Jacobsen, Jon; Husum, Bent; Staffeldt, Henrik

    2011-01-01

    The duration of spinal anesthesia with bupivacaine is often too long for day surgery. A recent study of patients presenting for transurethral surgery suggested that the addition of a small amount of lidocaine to intrathecal hyperbaric bupivacaine could shorten the duration of the sensory and motor...

  17. [The concentration of growth factors in patients with inherent and acquired shortenings of limbs bones].

    Science.gov (United States)

    Strogov, M V; Luneva, S N; Novikov, K I

    2013-04-01

    The article deals with the results of study of level of growth factors in blood serum of patients with inherent and post-traumatic shortenings of limbs' bones. The detection in blood serum the level of epidermal growth factor insulin-like growth factor I and angiopoetins is proposed to monitor in given patients the reparative bone formation.

  18. Differential Telomere Shortening in Blood versus Arteries in an Animal Model of Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Samira Tajbakhsh

    2015-01-01

    Full Text Available Vascular dysfunction is an early feature of diabetic vascular disease, due to increased oxidative stress and reduced nitric oxide (NO bioavailability. This can lead to endothelial cell senescence and clinical complications such as stroke. Cells can become senescent by shortened telomeres and oxidative stress is known to accelerate telomere attrition. Sirtuin 1 (SIRT1 has been linked to vascular health by upregulating endothelial nitric oxide synthase (eNOS, suppressing oxidative stress, and attenuating telomere shortening. Accelerated leukocyte telomere attrition appears to be a feature of clinical type 2 diabetes (T2D and therefore the telomere system may be a potential therapeutic target in preventing vascular complications of T2D. However the effect of T2D on vascular telomere length is currently unknown. We hypothesized that T2D gives rise to shortened leukocyte and vascular telomeres alongside reduced vascular SIRT1 expression and increased oxidative stress. Accelerated telomere attrition was observed in circulating leukocytes, but not arteries, in T2D compared to control rats. T2D rats had blunted arterial SIRT1 and eNOS protein expression levels which were associated with reduced antioxidant defense capacity. Our findings suggest that hyperglycemia and a deficit in vascular SIRT1 per se are not sufficient to prematurely shorten vascular telomeres.

  19. Development of a Shortened Form of the Fennema-Sherman Mathematics Attitudes Scales.

    Science.gov (United States)

    Mulhern, Fiona; Rae, Gordon

    1998-01-01

    Data from 196 Irish school children were analyzed and used to develop a shortened version of the Fennema-Sherman Mathematics Attitudes Scales (E. Fennema and J. Sherman, 1976). Internal consistency estimates of the reliability of scores on the whole scale and each of the subscales of the original and short form were favorable. (SLD)

  20. Bringing the School to the Children : Shortening the Path to EFA

    OpenAIRE

    Lehman, Douglas

    2003-01-01

    Recent education planning initiatives in West and Central Africa show that the path to EFA may be shortened considerably by reconsidering the way basic education is delivered in isolated rural communities. Since independence, education systems have been expanding rapidly and are now serving most of the easy-to-reach population. For progress to continue, the focus must be shifted toward the...

  1. Property Rights, Restrictions and Responsibilities

    DEFF Research Database (Denmark)

    Enemark, Stig

    Land Administration Systems are the basis for conceptualizing rights, restrictions and responsibilities related to people, policies and places. Property rights are normally concerned with ownership and tenure whereas restrictions usually control use and activities on land. Responsibilities relate...... more to a social, ethical commitment or attitude to environmental sustainability and good husbandry. This paper provides an overall understanding of the concept of land administration systems for dealing with rights, restrictions and responsibilities in future spatially enabled government. Finally...

  2. Enhanced muscle shortening and impaired Ca2+ channel function in an acute septic myopathy model.

    Science.gov (United States)

    Friedrich, Oliver; Hund, Ernst; von Wegner, Frederic

    2010-04-01

    Myopathies in critically ill patients are increasingly documented. Various animal models of chronic sepsis have been employed to investigate reduced membrane excitability or altered isometric contractility of skeletal muscle. In contrast, immediate changes occurring during acute sepsis are significantly under-characterised; L-type Ca(2+) channel function or isotonic shortening are examples. We recorded slowly activating L-type Ca(2+) currents (I (Ca)) in voltage-clamped single intact mouse skeletal muscle fibres and tested the effects of acute challenge with serum fractions from critical illness myopathy patients (CIM). Using a high-speed camera system, we simultaneously recorded unloaded fibre shortening during isotonic contractions with unprecedented temporal resolution (approximately 1,600 frames/s). Time courses of fibre lengths and shortening velocity were determined from automated imaging algorithms. CIM fractions acutely induced depression of I (Ca) amplitudes with no shifts in I (Ca)-V-relations. Voltage-dependent inactivation was unaltered and I (Ca) activation and inactivation kinetics were prolonged compared to controls. Unexpectedly, maximum unloaded speed of shortening was slightly faster following CIM serum applications, suggesting a direct action of CIM serum on weak-binding-state cross-bridges. Our results are compatible with a model where CIM serum might acutely reduce a fraction of functional L-type Ca(2+) channels and could account for reduced SR Ca(2+) release and force production in CIM patients. Acute increase in isotonic shortening velocity might be an early diagnostic feature suitable for testing in clinical studies. The acute challenge model is also robust against atrophy or fibre type changes that ordinarily would have to be considered in chronic sepsis models.

  3. Force depression and relaxation kinetics after active shortening and deactivation in mouse soleus muscle.

    Science.gov (United States)

    Van Noten, P; Van Leemputte, M

    2013-03-15

    After active shortening, isometric force production capacity of muscle is reduced (force depression, FD). The mechanism is incompletely understood but increasing cross-bridge detachment and/or decreasing attachment rate might be involved. Therefore we aimed to investigate the relation between work delivered during shortening (W), and change in half-relaxation time (Δ0.5RT) and change in the slow phase of muscle relaxation (Δkslow), considered as a marker for cross-bridge detachment rate, after shortening and after a short (0.7s) interruption of activation (deactivation). We hypothesized that shortening induces an accelerated relaxation related to W which is, similar to FD, largely abolished by a short deactivation. In 10 incubated supra-maximally stimulated mouse soleus muscles, we varied the amount of FD at L0 by varying shortening amplitude (0.6, 1.2 and 2.4mm). We found that W not only induces FD (R(2)=0.92) but also a dose dependent accelerated relaxation (R(2)=0.88 and R(2)=0.77 for respectively Δkslow and Δ0.5RT). In cyclic movements this is of functional significance, because the loss in force generating capacity might be (partially) compensated by faster relaxation. After a short deactivation, both FD and Δkslow were largely abolished but Δ0.5RT remained largely present. Under the assumption that Δkslow reflects a change in cross-bridge detachment rate, these results support the idea that FD is an intrinsic sarcomeric property originating from a work induced reduction of the number of force generating cross-bridges, however not via decreased attachment but via increased detachment rate.

  4. Residual force depression following muscle shortening is exaggerated by prior eccentric drop jump exercise.

    Science.gov (United States)

    Dargeviciute, Gintare; Masiulis, Nerijus; Kamandulis, Sigitas; Skurvydas, Albertas; Westerblad, Håkan

    2013-10-15

    We studied the relation between two common force modifications in skeletal muscle: the prolonged force depression induced by unaccustomed eccentric contractions, and the residual force depression (rFD) observed immediately after active shortening. We hypothesized that rFD originates from distortion within the sarcomeres and the extent of rFD: 1) correlates to the force and work performed during the shortening steps, which depend on sarcomeric integrity; and 2) is increased by sarcomeric disorganization induced by eccentric contractions. Nine healthy untrained men (mean age 26 yr) participated in the study. rFD was studied in electrically stimulated knee extensor muscles. rFD was defined as the reduction in isometric torque after active shortening compared with the torque in a purely isometric contraction. Eccentric contractions were performed as 50 repeated drop jumps with active deceleration to 90° knee angle, immediately followed by a maximal upward jump. rFD was assessed before and 5 min to 72 h after drop jumps. The series of drop jumps caused a prolonged force depression, which was about two times larger at 20-Hz than at 50-Hz stimulation. There was a significant correlation between increasing rFD and increasing mechanical work performed during active shortening both before and after drop jumps. In addition, a given rFD was obtained at a markedly lower mechanical work after drop jumps. In conclusion, the extent of rFD correlates to the mechanical work performed during active shortening. A series of eccentric contractions causes a prolonged reduction of isometric force. In addition, eccentric contractions exaggerate rFD, which further decreases muscle performance during dynamic contractions.

  5. Oxidative Stress-induced Telomere Length Shortening of Circulating Leukocyte in Patients with Obstructive Sleep Apnea

    Science.gov (United States)

    Kim, Kyung Soo; Kwak, Jin Wook; Lim, Su Jin; Park, Yong Kyun; Yang, Hoon Shik; Kim, Hyun Jik

    2016-01-01

    The main mechanism of pathogenesis which causes systemic complications in obstructive sleep apnea (OSA) patients is believed to be intermittent hypoxia-induced intermediary effect and it depends on the burden of oxidative stress during sleep. We aimed to search the predictive markers which reflect the burden of systemic oxidative stress in patients with OSA and whether excessive telomere length shortening is a characteristic feature that can assess oxidative stress levels. We used quantitative PCR to measure telomere length using peripheral blood genomic DNA. Telomere lengths were compared in an age- and body mass index (BMI)-dependent manner in 34 healthy volunteers and 43 OSA subjects. We also performed reactive oxygen species assay to measure the concentration of hydrogen peroxide in the peripheral blood of healthy volunteers and OSA subjects. We found that the serum concentration of hydrogen peroxide was considerably higher in OSA patients, and that this was closely related with the severity of OSA. Significantly shortened telomere length was observed in the circulating leukocytes of the peripheral blood of OSA patients, and telomere length shortening was aggravated more acutely in an age- and BMI-dependent manner. An inverse correlation was observed between the concentration of hydrogen peroxide and the telomere length of OSA patients and excessive telomere length shortening was also linked to severity of OSA. The results provided evidence that telomere length shortening or excessive cellular aging might be distinctive in circulating leukocyte of OSA patients and may be an predictive biomarker for reflect the burden of oxidative stress in the peripheral blood of OSA patients. PMID:27699083

  6. Two-Stage Surgical Treatment for Non-Union of a Shortened Osteoporotic Femur

    Directory of Open Access Journals (Sweden)

    Galal Zaki Said

    2013-01-01

    Full Text Available Introduction: We report a case of non-union with severe shortening of the femur following diaphysectomy for chronic osteomyelitis.Case Presentation: A boy, aged 16 years presented with a dangling and excessively short left lower limb. He was using an elbow crutch in his right hand to help him walk. He had a history of diaphysectomy for chronic osteomyelitis at the age of 9. Examination revealed a freely mobile non-union of the left femur. The femur was the seat of an 18 cm shortening and a 4 cm defect at the non-union site; the knee joint was ankylosed in extension. The tibia and fibula were 10 cm short. Considering the extensive shortening in the femur and tibia in addition to osteoporosis, he was treated in two stages. In stage I, the femoral non-union was treated by open reduction, internal fixation and iliac bone grafting. The patient was then allowed to walk with full weight bearing in an extension brace for 7 months. In Stage II, equalization of leg length discrepancy (LLD was achieved by simultaneous distraction of the femur and tibia by unilateral frames. At the 6 month follow- up, he was fully weight bearing without any walking aid, with a heel lift to compensate the 1.5 cm shortening. Three years later he reported that he was satisfied with the result of treatment and was leading a normal life as a university student.Conclusions: Two-stage treatment succeeded to restore about 20 cm of the femoral shortening in a severely osteoporotic bone. It has also succeeded in reducing the treatment time of the external fixator.

  7. Comparison of Vestibular Evoked Myogenic Potential and Caloric Tests Findings in Noise Induced Hearing Loss-Affected and Healthy Individuals

    Directory of Open Access Journals (Sweden)

    Farinoosh Fakharnia

    2010-06-01

    Full Text Available Background and Aim: Balance disturbance is one of the non-auditory effects of noisy industrial environments that is usually neglected. The aim of the current study was to investigate the effect of occupational noise on vestibular system among workers with noise-induced hearing loss (NIHL, based on both vestibular evoked myogenic potentials (VEMP and caloric tests.Methods: Thirty male workers with noise-induced hearing loss and thirty male matched controls were examined by VEMP and caloric tests. Study parameters included unilateral weakness, p13 and n23 latencies, and p13-n23 amplitude. Caloric test was performed only for 20 patients.Results: No significant difference was observed in unilateral weakness between the two groups. On the other hand, the difference in mean latencies of p13 in the right ear (p=0.003 and left ear (p=0.01 was significant between the two groups. However, the difference in n23 latency was significant only in the right ear (p=0.03. There was no significant difference between groups in p13-n23 amplitude.Conclusion: It seems that pars inferior of vestibule is the susceptible part in individuals with NIHL. In general, abnormal findings in both VEMP and caloric tests were more common compared to functional symptoms such as vertigo, which may be due to central compensation and the symmetry of the disorder.

  8. Caloric test and video-head-impulse: a study of vertigo/dizziness patients in a community hospital.

    Science.gov (United States)

    Mahringer, Andrea; Rambold, Holger A

    2014-03-01

    The head-impulse test (HIT) is an important test for examining unilateral vestibular hypofunction. The new video-head-impulse test (vHIT) is more sensitive and specific than the clinical bedside-head-impulse test (bHIT). Alternatively, one can test for vestibular hypofunction with the caloric irrigation test. Various studies showed that both tests may not always identify vestibular hypofunction; instead, the results of the tests might be contradictory. To evaluate the diagnostic value of these tests, we routinely measured patients exhibiting vertigo or dizziness at our community hospital with bithermal caloric irrigation, the bHIT and the vHIT. Only those patients (n = 172) with a pathological caloric irrigation test of more than 25 % unilateral weakness in the Jongkee's formula were included. Out of these patients, 41 % had a pathologic vHIT. Among the subgroup with acute symptoms (symptom onset within 5 days), 63 % had a pathological video-head-impulse, whereas only 33 % of the non-acute group (symptom onset more than 5 days) tested pathological. A pathological HIT depended on the disease stage, the amount of unilateral weakness in caloric examination and on the test itself.

  9. Amorphization Induced High Magneto-Caloric Effect of Gd55A120Ni25 Ternary Alloy

    Institute of Scientific and Technical Information of China (English)

    DING Ding; XIA Lei; YU Zhong-Hua; DONG Yuan-Da

    2008-01-01

    We report the amorphization induced high magneto-caloric effect (MCE) of recently developed Gd55Al15Ni30 bulk metallic glass (BMG). The magnetic properties of the Gd55Al15Ni30 BMG are investigated in comparison with that of its crystalline counterpart. It is found that amorphization can increase the saturation magnetization and decrease the hysteresis of Gd55Al15Ni30 alloys, which indicate the possible enhancement of MCE. The magnetic entropy changes and the refrigerant capacity of the BMG as well as the crystalline samples is calculated directly from isothermal magnetic measurements. The results show the amorphization induced high MCE of the alloy and the excellent refrigerant efficiency of Gd55A115Ni30 bulk metallic glass.

  10. Achieving tailorable magneto-caloric effect in the Gd-Co binary amorphous alloys

    Directory of Open Access Journals (Sweden)

    C. Wu

    2016-03-01

    Full Text Available Tailorable magnetic properties and magneto-caloric effect were achieved in the Gd-Co binary amorphous alloys. It was found that the Curie temperature (Tc of the GdxCo100-x (x=50, 53, 56, 58, 60 metallic glasses can be tuned by changing the concentration of Gd as Tc =708.8-8.83x, and the mechanism involved was investigated. On the other hand, a linear correlation between the peak value of magnetic entropy change (-Δ Smpeak and Tc-2/3 is found in the amorphous alloys with a linear correlation coefficients of above 0.992. Therefore, the -ΔSmpeak of the Gd-Co binary amorphous alloys under different magnetic fields can be easily tailored by adjusting the composition of the alloy.

  11. Hypophosphatemia and neurological changes secondary to oral caloric intake: a variant of hyperalimentation syndrome.

    Science.gov (United States)

    Silvis, S E; DiBartolomeo, A G; Aaker, H M

    1980-03-01

    Previous reports have described a syndrome of paresthesias, weakness, seizures and hypophosphatemia in patients and animals receiving intravenous hyperalimentation. In this report we describe a group of five patients who developed this syndrome while on oral caloric intake and three patients who received only modest amounts of hyperalimentation therapy. As an experimental corollary, studies were performed in starved and normal dogs with calories infused via an intragastric catheter. The serum inorganic phosphorus (Pi) fell slightly in normal animals from 4.8-2.5 mg. %. In the starved dogs with diarrhea or vomiting the Pi fell gradually from 4.8-1.6. In starved dogs without gastrointestinal symptoms the Pi fell precipitously from 3.7-1.4 mg % on the first day of infusion and remained at that level. Approximately 50% of the starved animals developed the neurological syndrome; none of the normal animals had neurological symptoms.

  12. Using Light Charged Particles to Probe the Asymmetry Dependence of the Nuclear Caloric Curve

    CERN Document Server

    McIntosh, Alan B; Kohley, Zachary; Cammarata, Paul J; Hagel, Kris; Heilborn, Lauren; Mabiala, Justin; May, Larry W; Marini, Paola; Raphelt, Andrew; Souliotis, George A; Wuenschel, Sara; Zarrella, Andrew; Yennello, Sherry J

    2013-01-01

    Recently, we observed a clear dependence of the nuclear caloric curve on neutron-proton asymmetry $\\frac{N-Z}{A}$ through examination of fully reconstructed equilibrated quasi-projectile sources produced in heavy ion collisions at E/A = 35 MeV. In the present work, we extend our analysis using multiple light charged particle probes of the temperature. Temperatures are extracted with five distinct probes using a kinetic thermometer approach. Additionally, temperatures are extracted using two probes within a chemical thermometer approach (Albergo method). All seven measurements show a significant linear dependence of the source temperature on the source asymmetry. For the kinetic thermometer, the strength of the asymmetry dependence varies with the probe particle species in a way which is consistent with an average emission-time ordering.

  13. Chaos theory applied to the caloric response of the vestibular system.

    Science.gov (United States)

    Aasen, T

    1993-12-01

    Developments in the field of nonlinear dynamics has given us a new conceptual framework for understanding the mechanisms involved in the regulation of complex nonlinear systems. This concept, called "chaos" or "deterministic chaos," has been applied to EKG, EEG, and other physiological signals, but not yet to the ENG signal. The underlying geometrical structure in chaotic dynamics is fractal (noninteger dimension), and calculating the fractal dimension of the electronystagmographic recording from caloric testing gave a dimension ranging from 3.3 to 7.7. This result demonstrates that the multidimensional vestibular system, with its numerous neurological pathways, can somehow reduce the degrees of freedom and give rise to an irregular dynamic low-dimensional behavior, which is associated with deterministic chaos.

  14. The effect of non-caloric sweeteners on cognition, choice, and post-consumption satisfaction.

    Science.gov (United States)

    Hill, Sarah E; Prokosch, Marjorie L; Morin, Amanda; Rodeheffer, Christopher D

    2014-12-01

    Consumers often turn to non-caloric sweeteners (NCS) as a means of promoting a healthy body weight. However, several studies have now linked their long-term use to increased weight gain, raising the question of whether these products produce unintended psychological, physiological, or behavioral changes that have implications for weight management goals. In the following, we present the results of three experiments bearing on this issue, testing whether NCS-consumption influences how individuals think about and respond to food. Participants in each of our three experiments were randomly assigned to consume a sugar-sweetened beverage, an unsweetened beverage, or a beverage sweetened with NCS. We then measured their cognition (Experiment 1), product choice (Experiment 2), and subjective responses to a sugar-sweetened food (Experiment 3). Results revealed that consuming NCS-sweetened beverages influences psychological processes in ways that - over time - may increase calorie intake.

  15. Transferência de calor e controle de temperatura em tubos capilares utilizados em eletroforese capilar

    OpenAIRE

    Rodrigo Danieli

    2005-01-01

    Este trabalho tem por objetivo estudar a transferência de calor em tubos capilares cilíndricos utilizados na técnica de separação de moléculas denominada Eletroforese Capilar. Esta técnica é usada, por exemplo, na análise de biomoléculas e no sequenciamento de DNA, onde o controle da temperatura está diretamente ligado ao desempenho destes métodos e à qualidade dos resultados. Para empregar esta técnica, tensões elétricas da ordem de 20 kV são aplicadas entre as extremidades dos tubos capilar...

  16. Shortening in the Central Andes at the transition to flat slab subduction

    Science.gov (United States)

    Safipour, R.; DeCelles, P. G.; Carrapa, B.; Kapp, P. A.; Gehrels, G. E.; Reiners, P. W.

    2011-12-01

    Shortening in the Central Andes is considered to decrease north and south of the apex of the Bolivian orocline, mainly owing to differences in the pre-existing stratigraphic architecture of the continental margin. Estimates of shortening in the central Andes of northern Argentina remain poorly documented, but are required for assessment of the regional kinematic history of the orogenic system. The problem is acute at the north to south transition from the high elevation Puna plateau to the lower elevation region of the Sierras Pampeanas intra-foreland block uplifts, which corresponds with a transition to a flat segment of the subducting Nazca plate. Although deformation in the Eastern Cordillera appears to have propagated forelandward from west to east, the trend in the Sierras Pampeanas is not clear from existing data. We mapped the structures along a roughly E-W transect at latitude 28°S in the Sierra de Las Planchadas of the northern Sierras Pampeanas to measure finite strain and kinematic indicators, and to develop a regional restorable cross section for measuring total shortening. We also sampled for low-T thermochronology in order to determine the timing of exhumation and inferred thrust propagation. A minimum of 40 km of shortening in the Sierra de Las Planchadas is estimated from our restored cross section. When added to the 20 km shortening documented in ranges to the east by previous studies, this brings the total minimum estimated shortening at this latitude to ~60 km. Apatite fission track ages from the hanging walls of thrusts are ~20 Ma, and apatite helium ages range from 10 Ma west of the range to 2.3 Ma in the Fiambalá basin which borders the range to the east. Cretaceous and Paleogene cooling ages are observed in ranges to the east of the Sierra de Las Planchadas, so the young cooling ages found in this study suggest that exhumation was complex and possibly diachronous at this latitude. To the extent that exhumation occurs simultaneously with

  17. Relationship between Spinal Cord Volume and Spinal Cord Injury due to Spinal Shortening.

    Directory of Open Access Journals (Sweden)

    Feng Qiu

    Full Text Available Vertebral column resection is associated with a risk of spinal cord injury. In the present study, using a goat model, we aimed to investigate the relationship between changes in spinal cord volume and spinal cord injury due to spinal shortening, and to quantify the spinal cord volume per 1-mm height in order to clarify a safe limit for shortening. Vertebral column resection was performed at T10 in 10 goats. The spinal cord was shortened until the somatosensory-evoked potential was decreased by 50% from the baseline amplitude or delayed by 10% relative to the baseline peak latency. A wake-up test was performed, and the goats were observed for two days postoperatively. Magnetic resonance imaging was used to measure the spinal cord volume, T10 height, disc height, osteotomy segment height, and spinal segment height pre- and postoperatively. Two of the 10 goats were excluded, and hence, only data from eight goats were analyzed. The somatosensory-evoked potential of these eight goats demonstrated meaningful changes. With regard to neurologic function, five and three goats were classified as Tarlov grades 5 and 4 at two days postoperatively. The mean shortening distance was 23.6 ± 1.51 mm, which correlated with the d-value (post-pre of the spinal cord volume per 1-mm height of the osteotomy segment (r = 0.95, p < 0.001 and with the height of the T10 body (r = 0.79, p = 0.02. The mean d-value (post-pre of the spinal cord volume per 1-mm height of the osteotomy segment was 142.87 ± 0.59 mm3 (range, 142.19-143.67 mm3. The limit for shortening was approximately 106% of the vertebral height. The mean volumes of the osteotomy and spinal segments did not significantly change after surgery (t = 0.310, p = 0.765 and t = 1.241, p = 0.255, respectively. Thus, our results indicate that the safe limit for shortening can be calculated using the change in spinal cord volume per 1-mm height.

  18. Serotonin in the solitary tract nucleus shortens the laryngeal chemoreflex in anaesthetized neonatal rats.

    Science.gov (United States)

    Donnelly, William T; Bartlett, Donald; Leiter, J C

    2016-07-01

    What is the central question of this study? Failure to terminate apnoea and arouse is likely to contribute to sudden infant death syndrome (SIDS). Serotonin is deficient in the brainstems of babies who died of SIDS. Therefore, we tested the hypothesis that serotonin in the nucleus of the solitary tract (NTS) would shorten reflex apnoea. What is the main finding and its importance? Serotonin microinjected into the NTS shortened the apnoea and respiratory inhibition associated with the laryngeal chemoreflex. Moreover, this effect was achieved through a 5-HT3 receptor. This is a new insight that is likely to be relevant to the pathogenesis of SIDS. The laryngeal chemoreflex (LCR), an airway-protective reflex that causes apnoea and bradycardia, has long been suspected as an initiating event in the sudden infant death syndrome. Serotonin (5-HT) and 5-HT receptors may be deficient in the brainstems of babies who die of sudden infant death syndrome, and 5-HT seems to be important in terminating apnoeas directly or in causing arousals or as part of the process of autoresuscitation. We hypothesized that 5-HT in the brainstem would limit the duration of the LCR. We studied anaesthetized rat pups between 7 and 21 days of age and made microinjections into the cisterna magna or into the nucleus of the solitary tract (NTS). Focal, bilateral microinjections of 5-HT into the caudal NTS significantly shortened the LCR. The 5-HT1a receptor antagonist, WAY 100635, did not affect the LCR consistently, nor did a 5-HT2 receptor antagonist, ketanserin, alter the duration of the LCR. The 5-HT3 specific agonist, 1-(3-chlorophenyl)-biguanide, microinjected bilaterally into the caudal NTS significantly shortened the LCR. Thus, endogenous 5-HT released within the NTS may curtail the respiratory depression that is part of the LCR, and serotonergic shortening of the LCR may be attributed to activation of 5-HT3 receptors within the NTS. 5-HT3 receptors are expressed presynaptically on C

  19. Protein degradation and post-deboning tenderization in broiler breast meat with different degrees of muscle shortening

    Science.gov (United States)

    Deboning broiler breast fillets prior to rigor mortis negatively influences tenderness due to sarcomere shortening. The effects of sarcomere shortening on muscle protein degradation and breast meat tenderization during post-deboning aging are not well understood. The objective of this study was to m...

  20. Does postsystolic motion or shortening predict recovery of myocardial function after primary percutanous coronary intervention?

    DEFF Research Database (Denmark)

    Terkelsen, Christian Juhl; Poulsen, Steen Hvitfeldt; Nørgaard, Bjarne Linde;

    2007-01-01

    or shortening appears more frequently in the acute phase in myocardial segments with impaired systolic function compared with normally functioning segments. However, presence of postsystolic contraction is not associated with improvement in strain or wall-motion score at follow-up, and does not seem......OBJECTIVE: The purpose of the study was to evaluate whether presence of postsystolic motion or shortening defined by Doppler tissue imaging may predict recovery of regional myocardial function in patients with ST-elevation myocardial infarction. METHODS: Echocardiography was performed a few hours......); and normal myocardial function in the acute phase (type E, n = 759). RESULTS: There were no differences among type A, B, C, and D segments with regard to the proportion presenting postsystolic tissue velocity equal to or greater than 1.0 cm/s (0.52, 0.54, 0.60, and 0.47, respectively, P = .20...

  1. A critical examination of the maximum velocity of shortening used in simulation models of human movement.

    Science.gov (United States)

    Domire, Zachary J; Challis, John H

    2010-12-01

    The maximum velocity of shortening of a muscle is an important parameter in musculoskeletal models. The most commonly used values are derived from animal studies; however, these values are well above the values that have been reported for human muscle. The purpose of this study was to examine the sensitivity of simulations of maximum vertical jumping performance to the parameters describing the force-velocity properties of muscle. Simulations performed with parameters derived from animal studies were similar to measured jump heights from previous experimental studies. While simulations performed with parameters derived from human muscle were much lower than previously measured jump heights. If current measurements of maximum shortening velocity in human muscle are correct, a compensating error must exist. Of the possible compensating errors that could produce this discrepancy, it was concluded that reduced muscle fibre excursion is the most likely candidate.

  2. Surveying of the deformed terraces and crust shortening rate in the northwestern Tarim Basin: Comment

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ The paper of Shen et al., entitled "Surveying of the deformed terraces and crust shortening rate in the northwest Tarim Basin", was published in Chinese Science Bulletin (Vol. 46, No. 12)[1]. Shen et al. found the deformation of Late Pleistocene to Holocene terraces of the Boguzi River across the Artushi Anticline in the northwest Tarim Basin close to the Pamir, and made level survey and differential GPS measurement, which is of great importance to geodynamics for research on the coupling of Tianshan Mountains uplifting and Tarim Basin depression. But their understanding to the deformation mechanics of terraces and the calculation methods of crustal shortening are open to discussion. Therefore, we discuss it with Shen Jun et al.

  3. Characterization of an ultrafast Bragg-Switch for shortening hard x-ray pulses

    Science.gov (United States)

    Sander, M.; Koc, A.; Kwamen, C. T.; Michaels, H.; Reppert, A. v.; Pudell, J.; Zamponi, F.; Bargheer, M.; Sellmann, J.; Schwarzkopf, J.; Gaal, P.

    2016-11-01

    We present a nanostructured device that functions as photoacoustic hard x-ray switch. The device is triggered by femtosecond laser pulses and allows for temporal gating of hard x-rays on picosecond (ps) timescales. It may be used for pulse picking or even pulse shortening in 3rd generation synchrotron sources. Previous approaches mainly suffered from insufficient switching contrasts due to excitation-induced thermal distortions. We present a new approach where thermal distortions are spatially separated from the functional switching layers in the structure. Our measurements yield a switching contrast of 14, which is sufficient for efficient hard x-ray pulse shortening. The optimized structure also allows for utilizing the switch at high repetition rates of up to 208 kHz.

  4. Telomere shortening leads to earlier age of onset in ALS mice

    Science.gov (United States)

    Linkus, Birgit; Wiesner, Diana; MeΔner, Martina; Karabatsiakis, Alexander; Scheffold, Annika; Rudolph, K. Lenhard; Thal, Dietmar R.; Weishaupt, Jochen H.; Ludolph, Albert C.; Danzer, Karin M.

    2016-01-01

    Telomere shortening has been linked to a variety of neurodegenerative diseases. Recent evidence suggests that reduced telomerase expression results in shorter telomeres in leukocytes from sporadic patients with amyotrophic lateral sclerosis (ALS) compared with healthy controls. Here, we have characterized telomere length in microglia, astroglia and neurons in human post mortem brain tissue from ALS patients and healthy controls. Moreover, we studied the consequences of telomerase deletion in a genetic mouse model for ALS. We found a trend towards longer telomeres in microglia in the brains of ALS patients compared to non-neurologic controls. Knockout of telomerase leading to telomere shortening accelerated the ALS phenotype in SOD1G93A–transgenic mice. Our results suggest that telomerase dysfunction might contribute to the age-related risk for ALS. PMID:26978042

  5. HULL GIRDER PROGRESSIVE COLLAPSE ANALYSIS USING IACS PRESCRIBED AND NLFEM DERIVED LOAD - END SHORTENING CURVES

    Directory of Open Access Journals (Sweden)

    Stanislav Kitarović

    2016-06-01

    Full Text Available This paper considers the hull girder ultimate strength of a bulk carrier at its midship section, as determined by an incremental-iterative progressive collapse analysis method prescribed by the International Association of Classification Societies Common Structural Rules for Bulk Carriers. In addition to the originally prescribed load – end shortening curves, curves determined by the nonlinear finite element method analysis (considering the influence of the idealized initial geometrical imperfections are also considered. Results obtained by both sets of curves are compared and discussed on both local (structural components load – end shortening curve and global (hull girder ulti-mate bending capacity and collapse sequence level, for both sagging and hogging cases.

  6. Telomeric noncoding RNA TERRA is induced by telomere shortening to nucleate telomerase molecules at short telomeres.

    Science.gov (United States)

    Cusanelli, Emilio; Romero, Carmina Angelica Perez; Chartrand, Pascal

    2013-09-26

    Elongation of a short telomere depends on the action of multiple telomerase molecules, which are visible as telomerase RNA foci or clusters associated with telomeres in yeast and mammalian cells. How several telomerase molecules act on a single short telomere is unknown. Herein, we report that the telomeric noncoding RNA TERRA is involved in the nucleation of telomerase molecules into clusters prior to their recruitment at a short telomere. We find that telomere shortening induces TERRA expression, leading to the accumulation of TERRA molecules into a nuclear focus. Simultaneous time-lapse imaging of telomerase RNA and TERRA reveals spontaneous events of telomerase nucleation on TERRA foci in early S phase, generating TERRA-telomerase clusters. This cluster is subsequently recruited to the short telomere from which TERRA transcripts originate during S phase. We propose that telomere shortening induces noncoding RNA expression to coordinate the recruitment and activity of telomerase molecules at short telomeres.

  7. Stretch-shortening cycle muscle power in women and men aged 18-81 years

    DEFF Research Database (Denmark)

    Edwén, C E; Thorlund, Jonas Bloch; Magnusson, Stig Peter;

    2014-01-01

    This study explored the age-related deterioration in stretch-shortening cycle (SSC) muscle power and concurrent force-velocity properties in women and men across the adult life span. A total of 315 participants (women: n = 188; men: n = 127) aged 18-81 years performed maximal countermovement jump...... on an instrumented force plate. Maximal SSC leg extension power expressed per kg body mass (Ppeak) was greater in men than in women across the adult age span (P ......This study explored the age-related deterioration in stretch-shortening cycle (SSC) muscle power and concurrent force-velocity properties in women and men across the adult life span. A total of 315 participants (women: n = 188; men: n = 127) aged 18-81 years performed maximal countermovement jumps...

  8. Influence of the heart rate on mean circumferential shortening velocity: echocardiographic study of 183 normal subjects.

    Science.gov (United States)

    Mangiarotti, R; Martinotti, R; Monzani, V; Sardella, F; Pierini, A; Pastori, M; Randazzo, A

    1986-01-01

    Echocardiography was used to explore the influence of independent variables (age, body surface area and heart rate) on the mean circumferential shortening velocity (MVCF) in 183 healthy subjects. Multiple stepwise regression analysis shows that heart rate is the only variable of the three just mentioned that influences MVCF. A regression equation is evolved and proposed as an index of MVCF correction for varying heart rates.

  9. Time course of isotonic shortening and the underlying contraction mechanism in airway smooth muscle.

    Science.gov (United States)

    Syyong, Harley T; Raqeeb, Abdul; Paré, Peter D; Seow, Chun Y

    2011-09-01

    Although the structure of the contractile unit in smooth muscle is poorly understood, some of the mechanical properties of the muscle suggest that a sliding-filament mechanism, similar to that in striated muscle, is also operative in smooth muscle. To test the applicability of this mechanism to smooth muscle function, we have constructed a mathematical model based on a hypothetical structure of the smooth muscle contractile unit: a side-polar myosin filament sandwiched by actin filaments, each attached to the equivalent of a Z disk. Model prediction of isotonic shortening as a function of time was compared with data from experiments using ovine tracheal smooth muscle. After equilibration and establishment of in situ length, the muscle was stimulated with ACh (100 μM) until force reached a plateau. The muscle was then allowed to shorten isotonically against various loads. From the experimental records, length-force and force-velocity relationships were obtained. Integration of the hyperbolic force-velocity relationship and the linear length-force relationship yielded an exponential function that approximated the time course of isotonic shortening generated by the modeled sliding-filament mechanism. However, to obtain an accurate fit, it was necessary to incorporate a viscoelastic element in series with the sliding-filament mechanism. The results suggest that a large portion of the shortening is due to filament sliding associated with muscle activation and that a small portion is due to continued deformation associated with an element that shows viscoelastic or power-law creep after a step change in force.

  10. Shortened Length of Stay Improves Financial Outcomes in Living Donor Kidney Transplantation

    Science.gov (United States)

    Villa, Manuel; Siskind, Eric; Sameyah, Emil; Alex, Asha; Blum, Mark; Tyrell, Richard; Fana, Melissa; Mishler, Marni; Godwin, Andrew; Kuncewitch, Michael; Alexander, Mohini; Israel, Ezra; Bhaskaran, Madhu; Calderon, Kellie; Jhaveri, Kenar D.; Sachdeva, Mala; Bellucci, Alessandro; Mattana, Joseph; Fishbane, Steven; Coppa, Gene; Molmenti, Ernesto

    2013-01-01

    Kidney transplantation is the preferred clinical and most cost-effective option for end-stage renal disease. Significant advances have taken place in the care of the transplant patients with improvements in clinical outcomes. The optimization of the costs of transplantation has been a constant goal as well. We present herein the impact in financial outcomes of a shortened length of stay after kidney transplant. PMID:24436592

  11. Effect of Preactivation on Torque Enhancement by the Stretch-Shortening Cycle in Knee Extensors.

    Science.gov (United States)

    Fukutani, Atsuki; Misaki, Jun; Isaka, Tadao

    2016-01-01

    The stretch-shortening cycle is one of the most interesting topics in the field of sport sciences, because the performance of human movement is enhanced by the stretch-shortening cycle (eccentric contraction). The purpose of the present study was to examine whether the influence of preactivation on the torque enhancement by stretch-shortening cycle in knee extensors. Twelve men participated in this study. The following three conditions were conducted for knee extensors: (1) concentric contraction without preactivation (CON), (2) concentric contraction with eccentric preactivation (ECC), and (3) concentric contraction with isometric preactivation (ISO). Muscle contractions were evoked by electrical stimulation to discard the influence of neural activity. The range of motion of the knee joint was set from 80 to 140 degrees (full extension = 180 degrees). Angular velocities of the concentric and eccentric contractions were set at 180 and 90 degrees/s, respectively. In the concentric contraction phase, joint torques were recorded at 85, 95, and 105 degrees, and they were compared among the three conditions. In the early phase (85 degrees) of concentric contraction, the joint torque was larger in the ECC and ISO conditions than in the CON condition. However, these clear differences disappeared in the later phase (105 degrees) of concentric contraction. The results showed that joint torque was clearly different among the three conditions in the early phase whereas this difference disappeared in the later phase. Thus, preactivation, which is prominent in the early phase of contractions, plays an important role in torque enhancement by the stretch-shortening cycle in knee extensors.

  12. Foreland shortening and crustal balancing in the Andes at 30°S latitude

    Science.gov (United States)

    Allmendinger, R. W.; Figueroa, D.; Synder, D.; Beer, J.; Mpodozis, C.; Isaacks, B. L.

    1990-08-01

    Excellent surface exposures, known Benioff zone geometry, a dynamic morphology, and the availability of industry seismic reflection data all make the Andes at 30°S an excellent transect for investigating crustal-scale balanced sections. 150-170 km of horizontal shortening has occurred in three major belts located between the trench and the foreland. The thin-skinned, east-verging Precordillera of western Argentina accounts for 60-75% of the total shortening and formed mostly since major volcanism ceased at ˜10 Ma. Industry seismic reflection data show that the décollement of the Precordillera belt is located anomalously deep at ˜15 km. The belt is dominated by fault propagation folds and contains several prominent out-of-sequence thrust faults. Seismic stratigraphie analysis shows that Miocene strata in the Iglesia Valley, located between the Precordillera and the crest of the Andes, accumulated in a piggy-back basin. Onlap relations on the western side indicate that the High Cordillera was uplifted as a major fault bend fold over a buried ramp. Thrusting in the two western belts, both in the High Cordillera of Chile, formed during the waning stages of arc volcanism, 11-16 Ma. and account for 25-40% of the shortening. The observed shortening is probably greater than can be accounted for with reasonable crustal thicknesses, indicating the possibility of continental truncation or erosion along the plate margin or an anomalously thick root held down by the nearly flat subducted Nazca Plate. Our preferred crustal geometry puts the ramp between upper and lower crustal deformation west of the high topography, requiring crustal scale tectonic wedging to thicken the crust beneath the crest of the Andes. This non-unique model provides a simple explanation of the first order morphology of the Andes at this latitude.

  13. Effect of Preactivation on Torque Enhancement by the Stretch-Shortening Cycle in Knee Extensors.

    Directory of Open Access Journals (Sweden)

    Atsuki Fukutani

    Full Text Available The stretch-shortening cycle is one of the most interesting topics in the field of sport sciences, because the performance of human movement is enhanced by the stretch-shortening cycle (eccentric contraction. The purpose of the present study was to examine whether the influence of preactivation on the torque enhancement by stretch-shortening cycle in knee extensors. Twelve men participated in this study. The following three conditions were conducted for knee extensors: (1 concentric contraction without preactivation (CON, (2 concentric contraction with eccentric preactivation (ECC, and (3 concentric contraction with isometric preactivation (ISO. Muscle contractions were evoked by electrical stimulation to discard the influence of neural activity. The range of motion of the knee joint was set from 80 to 140 degrees (full extension = 180 degrees. Angular velocities of the concentric and eccentric contractions were set at 180 and 90 degrees/s, respectively. In the concentric contraction phase, joint torques were recorded at 85, 95, and 105 degrees, and they were compared among the three conditions. In the early phase (85 degrees of concentric contraction, the joint torque was larger in the ECC and ISO conditions than in the CON condition. However, these clear differences disappeared in the later phase (105 degrees of concentric contraction. The results showed that joint torque was clearly different among the three conditions in the early phase whereas this difference disappeared in the later phase. Thus, preactivation, which is prominent in the early phase of contractions, plays an important role in torque enhancement by the stretch-shortening cycle in knee extensors.

  14. Disappearance of spasticity after selective dorsal rhizotomy does not prevent muscle shortening in children with cerebral palsy: a case report.

    Science.gov (United States)

    Spijker, Margje; Strijers, Rob L M; van Ouwerkerk, Willem J R; Becher, Jules G

    2009-05-01

    Selective dorsal rhizotomy is an effective treatment for spasticity in children with cerebral palsy who have a spastic motor disorder. It is hypothesized that muscle shortening is related to spasticity; the lack of stretch of a muscle is thought to be the cause of muscle shortening. If this is true, the treatment for spasticity should prevent the occurrence of muscle shortening during growth. We present the case of 1 child with cerebral palsy and spastic diplegia, for whom the treatment with selective dorsal rhizotomy was successful in improving the walking abilities. She did, however, develop muscle shortening during growth. In conclusion, the development of muscle shortening during growth in children with cerebral palsy and spastic paresis cannot be prevented by treatment for the spasticity alone.

  15. INFLUENCE OF SHORTENED AND LENGTHENED IMMOBILIZATION ON RAT SOLEUS MUSCLE ATROPHY

    Institute of Scientific and Technical Information of China (English)

    邢国刚; 樊小力; 吴苏娣; 宋新爱; 朱保恭; 唐斌

    2001-01-01

    Objective: To study the possible mechanism and prevention of disuse muscle atrophy. Methods: The shortened immobilization (plaster fixation) of rat' s soleus muscle (SOL) was used as the model of muscle and the lengthened immobilization of rat' s SOL muscle as "passive stretch" method. Types of skeletal muscle fibers were differentiated with m - ATPase staining technique. The changes of rat' s SOL muscle weight (wet weight) as well as the types and the mean cross - sectional area (CSA) of muscle fibers were examined respectively on day 2, 4,7, 14 and 21 under both shortened and lengthened immobilization and then the effect of passive stretch on soleus muscle atrophy in immobilized rats was observed. Results: When shortened immobilization was applied for 4 days, SOL muscle weight (wet weight) became lighter; the fiber crosssectional area (CSA) shrank and type Ⅰ muscle fibers started transforming into type Ⅱ, which all indicated immobilized muscles began to atrophy and as immobilization proceeded, muscle atrophy proceeded toward higher level. In contrast to that, when lengthened immobilization was applied, SOL muscle didn' t show any sign of atrophy until 7th day, and reached its highest level on day 14 and maintained that level even though immobilization continued. Conclusion: From the results, we conclude that passive stretch can either relieve or defer disuse muscle atrophy.

  16. Relative shortening velocity in locomotor muscles: turkey ankle extensors operate at low V/V(max).

    Science.gov (United States)

    Gabaldón, Annette M; Nelson, Frank E; Roberts, Thomas J

    2008-01-01

    The force-velocity properties of skeletal muscle have an important influence on locomotor performance. All skeletal muscles produce less force the faster they shorten and typically develop maximal power at velocities of approximately 30% of maximum shortening velocity (V(max)). We used direct measurements of muscle mechanical function in two ankle extensor muscles of wild turkeys to test the hypothesis that during level running muscles operate at velocities that favor force rather than power. Sonomicrometer measurements of muscle length, tendon strain-gauge measurements of muscle force, and bipolar electromyographs were taken as animals ran over a range of speeds and inclines. These measurements were integrated with previously measured values of muscle V(max) for these muscles to calculate relative shortening velocity (V/V(max)). At all speeds for level running the V/V(max) values of the lateral gastrocnemius and the peroneus longus were low (muscles were capable of producing 90% of peak isometric force but only 35% of peak isotonic power. V/V(max) increased in response to the demand for mechanical power with increases in running incline and decreased to negative values to absorb energy during downhill running. Measurements of integrated electromyograph activity indicated that the volume of muscle required to produce a given force increased from level to uphill running. This observation is consistent with the idea that V/V(max) is an important determinant of locomotor cost because it affects the volume of muscle that must be recruited to support body weight.

  17. Response of slow and fast muscle to hypothyroidism: maximal shortening velocity and myosin isoforms

    Science.gov (United States)

    Caiozzo, V. J.; Herrick, R. E.; Baldwin, K. M.

    1992-01-01

    This study examined both the shortening velocity and myosin isoform distribution of slow- (soleus) and fast-twitch (plantaris) skeletal muscles under hypothyroid conditions. Adult female Sprague-Dawley rats were randomly assigned to one of two groups: control (n = 7) or hypothyroid (n = 7). In both muscles, the relative contents of native slow myosin (SM) and type I myosin heavy chain (MHC) increased in response to the hypothyroid treatment. The effects were such that the hypothyroid soleus muscle expressed only the native SM and type I MHC isoforms while repressing native intermediate myosin and type IIA MHC. In the plantaris, the relative content of native SM and type I MHC isoforms increased from 5 to 13% and from 4 to 10% of the total myosin pool, respectively. Maximal shortening velocity of the soleus and plantaris as measured by the slack test decreased by 32 and 19%, respectively, in response to hypothyroidism. In contrast, maximal shortening velocity as estimated by force-velocity data decreased only in the soleus (-19%). No significant change was observed for the plantaris.

  18. Circular and longitudinal muscles shortening indicates sliding patterns during peristalsis and transient lower esophageal sphincter relaxation.

    Science.gov (United States)

    Patel, Nirali; Jiang, Yanfen; Mittal, Ravinder K; Kim, Tae Ho; Ledgerwood, Melissa; Bhargava, Valmik

    2015-09-01

    Esophageal axial shortening is caused by longitudinal muscle (LM) contraction, but circular muscle (CM) may also contribute to axial shortening because of its spiral morphology. The goal of our study was to show patterns of contraction of CM and LM layers during peristalsis and transient lower esophageal sphincter (LES) relaxation (TLESR). In rats, esophageal and LES morphology was assessed by histology and immunohistochemistry, and function with the use of piezo-electric crystals and manometry. Electrical stimulation of the vagus nerve was used to induce esophageal contractions. In 18 healthy subjects, manometry and high frequency intraluminal ultrasound imaging during swallow-induced esophageal contractions and TLESR were evaluated. CM and LM thicknesses were measured (40 swallows and 30 TLESRs) as markers of axial shortening, before and at peak contraction, as well as during TLESRs. Animal studies revealed muscular connections between the LM and CM layers of the LES but not in the esophagus. During vagal stimulated esophageal contraction there was relative movement between the LM and CM. Human studies show that LM-to-CM (LM/CM) thickness ratio at baseline was 1. At the peak of swallow-induced contraction LM/CM ratio decreased significantly (2). The pattern of contraction of CM and LM suggests sliding of the two muscles. Furthermore, the sliding patterns are in the opposite direction during peristalsis and TLESR.

  19. Field Monitoring of Column Shortenings in a High-Rise Building during Construction

    Directory of Open Access Journals (Sweden)

    Hyo Seon Park

    2013-10-01

    Full Text Available The automatic monitoring of shortenings of vertical members in high-rise buildings under construction is a challenging issue in the high-rise building construction field. In this study, a practical system for monitoring column shortening in a high-rise building under construction is presented. The proposed monitoring system comprises the following components: (1 a wireless sensing system and (2 the corresponding monitoring software. The wireless sensing system comprises the sensors and energy-efficient wireless sensing units (sensor nodes, master nodes, and repeater nodes, which automate the processes for measuring the strains of vertical members and transmitting the measured data to the remote server. The monitoring software enables construction administrators to monitor real-time data collected by the server via an Internet connection. The proposed monitoring system is applied to actual 66-floor and 72-floor high-rise buildings under construction. The system enables automatic and real-time measurements of the shortening of vertical members, which can result in more precise construction.

  20. Shortened Lifespan and Lethal Hemorrhage in a Hemophilia A Mouse Model.

    Directory of Open Access Journals (Sweden)

    Janice M Staber

    Full Text Available Hemophilia A animal models have helped advance our understanding of factor VIII deficiency. Previously, factor VIII deficient mouse models were reported to have a normal life span without spontaneous bleeds. However, the bleeding frequency and survival in these animals has not been thoroughly evaluated.To investigate the survival and lethal bleeding frequency in two strains of E-16 hemophilia A mice.We prospectively studied factor VIII deficient hemizygous affected males (n = 83 and homozygous affected females (n = 55 for survival and bleeding frequency. Animals were evaluated for presence and location of bleeds as potential cause of death.Hemophilia A mice had a median survival of 254 days, which is significantly shortened compared to wild type controls (p < 0.0001. In addition, the hemophilia A mice experienced hemorrhage in several tissues. This previously-underappreciated shortened survival in the hemophilia A murine model provides new outcomes for investigation of therapeutics and also reflects the shortened lifespan of patients if left untreated.

  1. Extreme femoral shortening: an approach to the chronically dislocated hip in the nonambulatory pediatric population.

    Science.gov (United States)

    Kalawadia, Jay V; Patel, Ronak M; Jensen, Layne; Sarwark, John

    2014-09-01

    There are many surgical techniques for treating the chronically dislocated, painful hip in patients with neuromuscular spasticity, but each has significant complication rates. We conducted a study to examine the outcomes of a novel technique, an extreme varus femoral shortening osteotomy, used in nonambulatory patients with neuromuscular spasticity. Patients who underwent the procedure were identified retrospectively by surgical codes. Medical records were reviewed for range of motion, pain and functional assessment, surgical indications, complications, and results. In addition, preoperative and postoperative radiographs were assessed, and caretaker questionnaires reviewed. Between 2001 and 2010, 1 surgeon performed 6 femoral shortening osteotomies in 5 nonambulatory patients with neuromuscular spasticity. In all 5 cases, there were improvements in pain, sitting tolerance, ease of hygiene, and ease of transfers at a minimum follow-up of 2 years (mean, 3.4 years). Postoperative complications included asymptomatic heterotopic ossification and recurrent subluxation. Extreme femoral shortening is a reproducible surgical technique that alleviates pain and makes hygiene easier in nonambulatory children with symptomatic hip dislocations caused by neuromuscular spasticity. Our complication rate was comparable to that of other procedures.

  2. Decreasing initial telomere length in humans intergenerationally understates age-associated telomere shortening.

    Science.gov (United States)

    Holohan, Brody; De Meyer, Tim; Batten, Kimberly; Mangino, Massimo; Hunt, Steven C; Bekaert, Sofie; De Buyzere, Marc L; Rietzschel, Ernst R; Spector, Tim D; Wright, Woodring E; Shay, Jerry W

    2015-08-01

    Telomere length shortens with aging, and short telomeres have been linked to a wide variety of pathologies. Previous studies suggested a discrepancy in age-associated telomere shortening rate estimated by cross-sectional studies versus the rate measured in longitudinal studies, indicating a potential bias in cross-sectional estimates. Intergenerational changes in initial telomere length, such as that predicted by the previously described effect of a father's age at birth of his offspring (FAB), could explain the discrepancy in shortening rate measurements. We evaluated whether changes occur in initial telomere length over multiple generations in three large datasets and identified paternal birth year (PBY) as a variable that reconciles the difference between longitudinal and cross-sectional measurements. We also clarify the association between FAB and offspring telomere length, demonstrating that this effect is substantially larger than reported in the past. These results indicate the presence of a downward secular trend in telomere length at birth over generational time with potential public health implications.

  3. Interpretação e utilidade da prova calórica Interpretation and use of caloric testing

    Directory of Open Access Journals (Sweden)

    Denise Utsch Gonçalves

    2008-06-01

    Full Text Available A prova calórica é o teste da avaliação otoneurológica que verifica a integridade do reflexo vestíbulo-ocular e possibilita avaliar cada labirinto separadamente. Os principais aspectos relacionados à realização, interpretação e utilidade da prova calórica foram revistos. MÉTODOS: Realizou-se revisão sistemática sobre as publicações ocorridas nos últimos cem anos sobre o assunto. Incluíram-se artigos originais transversais e longitudinais, de revisão e meta-análise. Excluíram-se revisões de papeleta, relatos de caso e editoriais. Os descritores utilizados foram: prova calórica, nistagmo, sistema vestibular, preponderância direcional, predomínio labiríntico, teste calórico monotermal, teste calórico com água gelada, fenômeno de Bell. Pesquisou-se as bases de dados COCHRAINE, MEDLINE, LILACS, CAPES. RESULTADOS: De 818 resumos de artigos, selecionou-se inicialmente 93 que preenchiam os critérios de inclusão. A leitura dos artigos resultou na seleção final de 55. Na análise dos artigos, enfatizou-se na discussão fundamentos da prova calórica, tipos de estimulação utilizados, prova calórica monotermal e com água gelada, questões relacionadas à interpretação dos resultados, variáveis e artefatos. COMENTÁRIOS FINAIS: os valores de referência utilizados na prova calórica podem variar de serviço para serviço, com ponto de corte definido a partir de estudos locais. Semiotécnica cuidadosa é fundamental para elevar a sensibilidade do exame.Caloric testing is an otoneurologic evaluation of the status of the vestibular-ocular reflex; it allows an evaluation of each labyrinth separately. The main aspects on the use and interpretation of caloric testing are reviewed. METHOD: A systematic review of papers published in the past one hundred years on caloric testing was undertaken. The inclusion criteria were: cross-sectional, longitudinal, original articles, reviews and meta-analyses. Reviews of patient charts

  4. Función de Green para la ecuación hiperbólica de transmisión del calor.

    OpenAIRE

    2008-01-01

    En esta memoria se recoge fundamentalmente el estudio, bajo el punto de vista del modelo hiperbólico de transmisión del calor, de un problema de transmisión del calor basado en el procesado de materiales mediante pulsos de láser de alta intensidad y tiempos de aplicación muy cortos. Este tipo de problemas lleva asociado el desarrollo de un riguroso estudio matemático para la ecuación hiperbólica de transmisión del calor que nos permita establecer los fundamentos teóricos para el cálculo ...

  5. El golpe de calor en la actividad física y el deporte (versión traducida al español)

    OpenAIRE

    Hosokawa, Yuri; Adams, William M; Stearns, Rebecca L.; Casa, Douglas J.

    2014-01-01

    El golpe de calor por esfuerzo (GCE) es una de las causas principales de muerte súbita durante el deporte y la actividad física. Solamente en el fútbol americano han ocurrido 46 muertes documentadas en los EE.UU. entre 1995 y 2010. En el 2003, la asociación responsable por los deportes universitarios de los EE.UU. estableció pautas obligatorias de aclimatización al calor, las cuales tuvieron como resultado una disminución exitosa en el número de muertes por golpe de calor en ese deporte. Sin ...

  6. Percepción de sed e ingesta de líquido después del ejercicio en el calor

    OpenAIRE

    Aragón-Vargas, Luis Fernando; Capitán Jiménez, Catalina

    2016-01-01

    La sudoración durante el ejercicio en el calor puede producir una deshidratación importante que debe reponerse mediante la ingesta de líquido. Este estudio experimental evalúa la afirmación de que la ingesta voluntaria de agua, que supuestamente ocurre como respuesta a la sed, es suficiente para reponer el líquido perdido. 14 participantes realizaron ejercicio en dos ocasiones en un cuarto de clima controlado programado para calor seco (tbs = 33.8C, HR = 53%) y calor húmedo (tbs = 32.1C y H...

  7. Dyslipidemia and chronic inflammation markers are correlated with telomere length shortening in Cushing's syndrome.

    Directory of Open Access Journals (Sweden)

    Anna Aulinas

    Full Text Available Cushing's syndrome (CS increases cardiovascular risk (CVR and adipocytokine imbalance, associated with an increased inflammatory state. Telomere length (TL shortening is a novel CVR marker, associated with inflammation biomarkers. We hypothesized that inflammatory state and higher CVR in CS might be related to TL shortening, as observed in premature aging.To evaluate relationships between TL, CVR and inflammation markers in CS.In a cross-sectional study, 77 patients with CS (14 males, 59 pituitary-, 17 adrenal- and 1 ectopic-origin; 21 active disease and 77 age-, gender-, smoking-matched controls were included. Total white blood cell TL was measured by TRF-Southern technique. Clinical data and blood samples were collected (lipids, adrenal function, glucose. Adiponectin, interleukin-6 (IL6 and C-reactive protein (CRP were available in a subgroup of patients (n=32. Correlations between TL and clinical features were examined and multiple linear regression analysis was performed to investigate potential predictors of TL.Dyslipidemic CS had shorter TL than non-dyslipidemic subjects (7328±1274 vs 7957±1137 bp, p<0.05. After adjustment for age and body mass index, cured and active CS dyslipidemic patients had shorter TL than non-dyslipidemic CS (cured: 7187±1309 vs 7868±1104; active: 7203±1262 vs 8615±1056, respectively, p<0.05. Total cholesterol and triglycerides negatively correlated with TL (r-0.279 and -0.259, respectively, p<0.05, as well as CRP and IL6 (r-0.412 and -0.441, respectively, p<0.05. No difference in TL according the presence of other individual CVR factors (hypertension, diabetes mellitus, obesity were observed in CS or in the control group. Additional TL shortening was observed in dyslipidemic obese patients who were also hypertensive, compared to those with two or less CVR factors (6956±1280 vs 7860±1180, respectively, p<0.001. Age and dyslipidemia were independent negative predictors of TL.TL is shortened in dyslipidemic CS

  8. Remarks on restricted Nevanlinna transforms

    CERN Document Server

    Jankowski, Lech

    2010-01-01

    The Nevanlinna transform K(z), of a measure and a real constant, plays an important role in the complex analysis and more recently in the free probability theory (boolean convolution). It is shown that its restriction k(it) (the restricted Nevanlinna transform) to the imaginary axis can be expressed as the Laplace transform of the Fourier transform (characteristic function) of the corresponding measure. Finally, a relation between the Voiculescu and the boolean convolution is indicated.

  9. Dietary protein restriction decreases oxidative protein damage, peroxidizability index, and mitochondrial complex I content in rat liver.

    Science.gov (United States)

    Ayala, Victoria; Naudí, Alba; Sanz, Alberto; Caro, Pilar; Portero-Otin, Manuel; Barja, Gustavo; Pamplona, Reinald

    2007-04-01

    Caloric restriction (CR) decreases oxidative damage, which contributes to the slowing of aging rate. It is not known if such decreases are due to calories themselves or specific dietary components. In this work, the ingestion of proteins of Wistar rats was decreased by 40% below that of controls. After 7 weeks, the liver of the protein-restricted (PR) animals showed decreases in oxidative protein damage, degree of membrane unsaturation, and mitochondrial complex I content. The results and previous information suggest that the decrease in the rate of aging induced by PR can be due in part to decreases in mitochondrial reactive oxygen species production and DNA and protein oxidative modification, increases in fatty acid components more resistant to oxidative damage, and decreased expression of complex I, analogously to what occurs during CR. Recent studies suggest that those benefits of PR could be caused, in turn, by the lowered methionine intake of that dietary manipulation.

  10. Modelo descritivo do fluxo de calor em soldagem a arco visando o conceito de calor imposto efetivo Descriptive model of the heat flow in arc welding targeting the concept of effective heat input

    Directory of Open Access Journals (Sweden)

    Américo Scotti

    2012-06-01

    Full Text Available O objetivo do presente trabalho é propor um modelo global para descrever o fluxo de calor em soldagem a arco, visando o entendimento dos fenômenos relacionados com o fluxo de calor. A tentativa é suprir uma lacuna do conhecimento gerado entre a aplicação de modelos analíticos simplificados (não totalmente realistas e de modelos numéricos (que mascaram a visão física dos fenômenos. Inicia-se propondo uma descrição mais física para a razão da queda de tensão num arco, baseada na geração e perda de calor para se manter o equilíbrio da desionização e reionização, em contraste com a abordagem em que o arco é comparável a um resistor elétrico. Em seguida, se propõe um modelo descritivo da subsistência térmica de um arco, para qualificar as formas de transferência de calor do arco para a chapa. Um segundo modelo descritivo é então proposto para explicar como o calor entra, difunde e sai da chapa durante a soldagem. Finalmente, é discutido como a aplicação destes dois modelos de forma global permite entender que nem todo o fluxo de calor do arco para a chapa vai afetar a velocidade de resfriamento nas regiões do material aquecidas. Culmina-se com a proposta do emprego do termo Calor Imposto Efetivo como meio de evidenciar o parâmetro de calor de importância a ser determinado em soldagem.The objective of the present paper is to propose a global model for describing heat flow in arc welding, aiming the understanding of the phenomena involved. The attempt is to fill out a gap of knowledge which has been generated between the application of simplified analytical models (not totally realistic and numerical models (that disguises the physics of the phenomena. Initially, a physic-oriented description of the reasons for welding arc voltage drop is presented. This description is based on the heat generation and its losses to maintain the balance between deionization and reionization, in contrast to the approach that the arc

  11. High Caloric Diet for ALS Patients: High Fat, High Carbohydrate or High Protein

    Directory of Open Access Journals (Sweden)

    Sarvin Sanaie

    2015-01-01

    . They showed that patients in the highcarbohydrate/high-calorie groups gained 0.39 kg more weight per month, compared with 0.11kg per month in the control group, and there was an average weight loss of 0.46 kg per month in the high-fat/high-calorie group. However, there are some concerns that highcarbohydrate low-fat diets might increase the risk of ALS and these findings should be interpreted with caution (4. Furthermore, according to Wills et al. high fat-high caloric diets could not be ideal regimens for these patients due to the associated gastrointestinal complications (3. Dorst and associates, in their study, showed that high caloric food supplement with high fat is suitable to establish body weight compared to high carbohydrate formula. Hence, it seems that high protein-high caloric diets could be more appropriate options for both improving negative nitrogen balance and decreasing muscle atrophy in patients with ALS based on the pathophysiology of proteinenergy malnutrition and hypermetabolism which is thought to be due to mitochondria problem. The multifactorial pathophysiology of ALS has resulted in hypotheses that there may be subgroups of patients, eventually defined by a specific underlying etiology or clinical presentation, which selectively respond to a particular regimen. Consequently, further RCTs with larger sample size are required to clarify the best regimen for weight gain and improved survival in ALS patients and it seems that personalized nutritional support or combined regimens might be the best way and could improve the quality of life considering the complex pathophysiology of malnutrition.

  12. Protein-pacing caloric-restriction enhances body composition similarly in obese men and women during weight loss and sustains efficacy during long-term weight maintenance

    DEFF Research Database (Denmark)

    Arciero, Paul J; Edmonds, Rohan; He, Feng

    2016-01-01

    /day) in obese adults. Less is known whether obese men and women respond similarly to P-CR during weight loss (WL) and whether a modified P-CR (mP-CR) is more efficacious than a HH diet during long-term (52 week) weight maintenance (WM). The purposes of this study were to evaluate the efficacy of: (1) P......-CR on TBF, ABF, resting metabolic rate (RMR), and biomarkers between obese men and women during WL (weeks 0-12); and (2) mP-CR compared to a HH diet during WM (weeks 13-64). During WL, men (n = 21) and women (n = 19) were assessed for TBF, ABF, VAT, RMR, and biomarkers at weeks 0 (pre) and 12 (post). Men......) completed WM. mP-CR regained significantly less body weight (6%), TBF (12%), and ABF (17%) compared to HH (p diet....

  13. Serum Polychlorinated Biphenyls Increase and Oxidative Stress Decreases with a Protein-Pacing Caloric Restriction Diet in Obese Men and Women

    Science.gov (United States)

    He, Feng; Zuo, Li; Ward, Emery; Arciero, Paul J.

    2017-01-01

    The purposes were to compare the effects of a: (1) 12-week P-CR weight loss (WL) diet (Phase 1) between obese men and women and; (2) 52-week modified P-CR (mP-CR) vs. heart healthy (HH) weight maintenance (WM) diet (Phase 2) on serum PCBs and oxidative stress biomarkers (thiobarbituric acid reactive substances, TBARS; total antioxidant capacity, TAC) in 40 obese participants (men, n = 21; women, n = 19). Participants received dietary counseling and monitoring of compliance. PCBs, TBARS, and TAC were assessed at weeks −1 (CON), 12 (WL), and 64 (WM). Following WL (Week 12), concomitant with reductions in TBARS (0.24 ± 0.15 vs. 0.18 ± 0.11 µM; p 0.42, p < 0.05) and negatively correlated with body weight, fat mass, and abdominal fat (r < −0.46, p < 0.02). Our results support mobilization of stored PCBs as well as enhanced redox status following a 12-week P-CR WL diet. Additionally, a 52-week mP-CR WM diet demonstrated an advantage in preventing weight gain relapse accompanied by an increase in circulating PCBs compared to a traditional HH diet. PMID:28075418

  14. Serum Polychlorinated Biphenyls Increase and Oxidative Stress Decreases with a Protein-Pacing Caloric Restriction Diet in Obese Men and Women

    Directory of Open Access Journals (Sweden)

    Feng He

    2017-01-01

    Full Text Available The purposes were to compare the effects of a: (1 12-week P-CR weight loss (WL diet (Phase 1 between obese men and women and; (2 52-week modified P-CR (mP-CR vs. heart healthy (HH weight maintenance (WM diet (Phase 2 on serum PCBs and oxidative stress biomarkers (thiobarbituric acid reactive substances, TBARS; total antioxidant capacity, TAC in 40 obese participants (men, n = 21; women, n = 19. Participants received dietary counseling and monitoring of compliance. PCBs, TBARS, and TAC were assessed at weeks −1 (CON, 12 (WL, and 64 (WM. Following WL (Week 12, concomitant with reductions in TBARS (0.24 ± 0.15 vs. 0.18 ± 0.11 µM; p < 0.01, PCB serum concentrations (86.7 ± 45.6 vs. 115.6 ± 65.9 ng/g lipid; p < 0.01 and TAC (18.9 ± 2.6 vs. 19.9 ± 2.3 nmol/mL; p < 0.02 were increased similarly in men and women. At the end of WM (Week 64, a significant effect of time × group interaction was observed for % change in PCB 170 and 187; whereby mP-CR values were higher compared to HH (PCB170: 19.31% ± 26.48% vs. −6.61% ± 28.88%, p = 0.02; PCB187: −3.04% ± 17.78% vs. −21.4% ± 27.31%, p = 0.04. PCB changes were positively correlated with TBARS levels (r > 0.42, p < 0.05 and negatively correlated with body weight, fat mass, and abdominal fat (r < −0.46, p < 0.02. Our results support mobilization of stored PCBs as well as enhanced redox status following a 12-week P-CR WL diet. Additionally, a 52-week mP-CR WM diet demonstrated an advantage in preventing weight gain relapse accompanied by an increase in circulating PCBs compared to a traditional HH diet.

  15. Tolerancia al calor y humedad atmosférica de diferentes grupos raciales de ganado bovino

    Directory of Open Access Journals (Sweden)

    Ariel Guillén T

    2011-04-01

    Full Text Available Objetivo. Comparar algunas respuestas fisiológicas al calor y humedad atmosférica entre bovinos Chinampos (Bos taurus; Ch, ½ Charolais ½ Brahman (CB, Holstein (H y Jersey (J. Materiales y métodos. Se realizó un estudio en La Paz, México. Se utilizaron 12 vacas H, 10 J, 15 Ch y 8 CB. Durante el verano se midieron cada semana (a las 0600 y 1600 horas la frecuencia respiratoria (FR y temperatura rectal (TR. Se registraron las variables climáticas para calcular el índice de temperatura-humedad (ITH. Resultados. Durante todo el verano, la FR en los cuatro grupos estuvo por encima de los valores fisiológicos para el ganado bovino, siendo superior en H y J que en Ch y CB (p<0.01. En todos los grupos, la TR estuvo dentro de los límites fisiológicos de la especie estudiada. El grupo racial más afectado fue H (p<0.05. Cuando las constantes fisiológicas fueron analizadas dentro de cada una de tres categorías de ITH (<72, ≥72<78, y ≥78, las vacas H y J mostraron FR superior a las Ch y CB (p<0.01. La TR aumentó conforme se elevó el ITH siendo más marcado en J y H. El incremento de la FR entre la mañana y la tarde de cada día de medición fue mayor en H y J que en Ch y CB (p<0.05. La TR se incrementó más en H que en Ch (p<0.05. Conclusiones. Los grupos raciales más tolerantes al estrés por calor, determinado con base en FR y TR fueron Ch y CB.

  16. Heat transfer in simple houses; Transferencia de calor en casas habitacion

    Energy Technology Data Exchange (ETDEWEB)

    Porta, Miguel Angel; Rubio, Eduardo; Fernandez, Jose Luis [Centro de Investigaciones Biologicas del Noroeste, Baja California Sur, (Mexico); Gomez Munoz, Victor [Centro Interdiciplinario de Ciencias Marinas, Baja California Sur (Mexico)

    2000-07-01

    A lumped parameter model is used to represent, with a high degree of precision, the temperature and comfort evolution with the time of a simple house, under any hot, extreme weather variation. Results are validated by experimental work in physical models, built to scale 1:2, with materials and building techniques typical of social interest housing in Baja California, Mexico. With the mathematical model properly calibrated, adequately validated heat transfer coefficients between walls, ceiling and windows are calculated. Sensitivity analyses lead to values of heat loads in simple houses with varying shapes, orientation, shading devices, and construction materials and techniques. Energy balance in the present work is achieved by means of three simultaneous equations, each depicting energy equilibrium in one of the basic building elements: the window glazing, the building materials, and inside air. Simultaneous solution of the equations is accomplished with of the Kutta method, which yields the representative temperature along the day of each of the components, while heat flow among them is calculated, together with thermal exchange with the environment. Comfort levels, energy consumption and saving are hence easily derived, and the economical pertinence of passive elements can be evaluated. [Spanish] Este trabajo presenta un modelo matematico de parametros concentrados que representa, de manera apropiada, el comportamiento de una casa habitacion tipica a lo largo de un dia cualquiera. Los resultados se validan mediante la experimentacion en modelo fisico, donde se ensayan casetas de material y dimensiones similares a las casas de interes social, a escala 1:2. Una vez que se ha calibrado el modelo, se pueden determinar, mediante corridas apropiadas en computadora, los coeficientes especificos de transferencia de calor en muros, ventanas y techo. Los analisis subsecuentes de sensibilidad producen informacion util para conocer los requerimientos energeticos de cada casa

  17. Absorption heat pump integrated in an effluent purification system; Bomba de calor por absorcion integrada a un sistema de purificacion de efluentes

    Energy Technology Data Exchange (ETDEWEB)

    Santoyo, Socrates; Siqueiros, Javier; Heard, Christopher; Santoyo, Edgar [Instituto de Investigaciones Electricas, Cuernavaca (Mexico)

    1996-12-31

    The results derived of the integration of an absorption heat pump to an industrial effluents purification system, are presented. The advantages of these heat pumps with respect to heat pumps by mechanical compression of vapor, as well as the advantages in using absorption heat pumps in simple distillation systems, are mentioned. Finally, a description is made of the equipment designed and built, as well as the results obtained in a preliminary test. [Espanol] Se presentan los resultados derivados de la integracion de una bomba de calor por absorcion a un sistema de purificacion de efluentes industriales. Se mencionan las ventajas de este tipo de bombas de calor con respecto a las de calor por compresion mecanica de vapor, asi como las ventajas de usar bombas de calor en sistemas de destilacion simple. Finalmente, se describe el equipo disenado y construido, asi como los resultados obtenidos de una prueba preliminar.

  18. Calores de Solución y Propiedades Termodinámicas Relacionadas: Un método Gráfico General de Cálculo

    OpenAIRE

    Alfredo Gómez O.

    2009-01-01

    Se presenta un método gráfico) de cálculo) con el cual es posible evaluar a partir de datos de calor de solución. diferentes propiedades termodinámicas de interés tales como: calores)res diferenciales de solución del soluto y del solvente. A HD,P 2 V ^ HOIF.I • calor de solución a dilución infinita A tH°; entalpias molares parciales relativas del soluto y del solvente. Lj y L,. y la entalpia molar aparente relativa, L^. El método está basado en la representación gráfica del calor integral de...

  19. Improved magneto-caloric effect of the Gd50Co50 metallic glass by minor Si addition

    Science.gov (United States)

    Tang, B. Z.; Yu, P.; Ding, D.; Wu, C.; Xia, L.

    2017-02-01

    In the present work, we studied the effect of minor Si addition on the magneto-caloric effect (MCE) of the Gd50Co50 metallic glass. The Gd50Co50-xSix (x=2, 5) as-spun ribbons show typical amorphous characteristics in structure and magneto-caloric behaviors. The peak values for the magnetic entropy change (-ΔSmpeak) of the Gd50Co50-xSix (x=0, 2, 5) metallic glasses increase significantly with the addition of Si. The mechanism for the enhanced MCE by minor addition of Si was investigated by revealing the relationship between -ΔSmpeak and the Curie temperature in the Gd-Co-based amorphous ribbons.

  20. Cinética da transferência de calor em materiais com mudança de fase

    OpenAIRE

    Vitorino, Nuno Miguel Dias

    2013-01-01

    É extensa a bibliografia dedicada a potenciais aplicações de materiais com mudança de fase na regulação térmica e no armazenamento de calor ou de frio. No entanto, a baixa condutividade térmica impõe limitações numa grande diversidade de aplicações com exigências críticas em termos de tempo de resposta curto ou com requisitos de elevada potência em ciclos de carga/descarga de calor latente. Foram desenvolvidos códigos numéricos no sentido de obter soluções precisas para descrever a c...

  1. Fish oil supplementation is beneficial on caloric intake, appetite and mid upper arm muscle circumference in children with leukaemia.

    Science.gov (United States)

    Abu Zaid, Zalina; Shahar, Suzana; Jamal, A Rahman A; Mohd Yusof, Noor Aini

    2012-01-01

    A randomised trial was carried out to determine the effect of supplementation of fish oil among 51 children with leukaemia aged 4 to 12 years on appetite level, caloric intake, body weight and lean body mass. They were randomly allocated into the trial group (TG) and the control group (CG). At baseline, 30.8% of TG subjects and 44.0% of CG subjects were malnourished and 7.7% of subject from TG and 28.0% from CG were classified as stunted. The majority of subjects from TG and CG were in the mild malnutrition category for mid upper arm muscle circumference (MUAMC)-for-age. The TG group showed significant increment in MUAMC (0.13 cm vs -0.09 cm) compared with CG at 8 weeks (pappetite level (0.12±0.33) (pappetite level, caloric intake and MUAMC among children with leukaemia.

  2. Simulação Monte Carlo com Repesagem Aplicada ao Calor Específico de Sólidos

    Directory of Open Access Journals (Sweden)

    Silva Roberto da

    2002-01-01

    Full Text Available Apresenta-se uma estimativa numérica para a contribuição das vibrações da rede para o calor específico de um sólido cristalino. O método Monte Carlo é utilizado tanto em sua forma original quanto em sua versão mais moderna, que emprega a técnica da repesagem para extrair mais informações de cada simulação. Mostra-se como obter curvas contínuas para grandezas como a energia e o calor específico em função da temperatura a partir de simulação feita em apenas uma temperatura. Os resultados analíticos são incluídos para facilitar a comparação com os resultados da simulação.

  3. Varying mechanical coupling along the Andean margin: Implications for trench curvature, shortening and topography

    Science.gov (United States)

    Iaffaldano, G.; Di Giuseppe, E.; Corbi, F.; Funiciello, F.; Faccenna, C.; Bunge, H.-P.

    2012-03-01

    Convergent margins often exhibit spatial and temporal correlations between trench curvature, overriding plate shortening and topography uplift that provide insights into the dynamics of subduction. The Andean system, where the Nazca plate plunges beneath continental South America, is commonly regarded as the archetype of this class of tectonics systems. There is distinctive evidence that the degree of mechanical coupling between converging plates, i.e. the amount of resistive force mutually transmitted in the direction opposite to their motions, may be at the present-day significantly higher along the central Andean margin compared to the northern and southern limbs. However quantitative estimates of such resistance are still missing and would be desirable. Here we present laboratory models of subduction performed to investigate quantitatively how strong lateral coupling variations need to be to result in trench curvature, tectonic shortening and distribution of topography comparable to estimates from the Andean margin. The analogue of a two-layers Newtonian lithosphere/upper mantle system is established in a silicone putty/glucose syrup tank-model where lateral coupling variations along the interface between subducting and overriding plates are pre-imposed. Despite the simplicity of our setup, we estimate that coupling in the central margin as large as 20% of the driving force is sufficient to significantly inhibit the ability of the experimental overriding plate to slide above the subducting one. As a consequence, the central margin deforms and shortens more than elsewhere while the trench remains stationary, as opposed to the advancing lateral limbs. This causes the margin to evolve into a peculiar shape similar to the present-day trench of the Andean system.

  4. New insight into the shortening of the collagen fibril D-period in human cornea.

    Science.gov (United States)

    Jastrzebska, Maria; Tarnawska, Dorota; Wrzalik, Roman; Chrobak, Artur; Grelowski, Michal; Wylegala, Edward; Zygadlo, Dorota; Ratuszna, Alicja

    2017-02-01

    Collagen fibrils type I display a typical banding pattern, so-called D-periodicity, of about 67 nm, when visualized by atomic force or electron microscopy imaging. Herein we report on a significant shortening of the D-period for human corneal collagen fibrils type I (21 ± 4 nm) upon air-drying, whereas no changes in the D-period were observed for human scleral collagen fibrils type I (64 ± 4 nm) measured under the same experimental conditions as the cornea. It was also found that for the corneal stroma fixed with glutaraldehyde and air-dried, the collagen fibrils show the commonly accepted D-period of 61 ± 8 nm. We used the atomic force microscopy method to image collagen fibrils type I present in the middle layers of human cornea and sclera. The water content in the cornea and sclera samples was varying in the range of .066-.085. Calculations of the D-period using the theoretical model of the fibril and the FFT approach allowed to reveal the possible molecular mechanism of the D-period shortening in the corneal collagen fibrils upon drying. It was found that both the decrease in the shift and the simultaneous reduction in the distance between tropocollagen molecules can be responsible for the experimentally observed effect. We also hypothesize that collagen type V, which co-assembles with collagen type I into heterotypic fibrils in cornea, could be involved in the observed shortening of the corneal D-period.

  5. Human probing behavior of Aedes aegypti when infected with a life-shortening strain of Wolbachia.

    Directory of Open Access Journals (Sweden)

    Luciano A Moreira

    Full Text Available BACKGROUND: Mosquitoes are vectors of many serious pathogens in tropical and sub-tropical countries. Current control strategies almost entirely rely upon insecticides, which increasingly face the problems of high cost, increasing mosquito resistance and negative effects on non-target organisms. Alternative strategies include the proposed use of inherited life-shortening agents, such as the Wolbachia bacterium. By shortening mosquito vector lifespan, Wolbachia could potentially reduce the vectorial capacity of mosquito populations. We have recently been able to stably transinfect Aedes aegypti mosquitoes with the life-shortening Wolbachia strain wMelPop, and are assessing various aspects of its interaction with the mosquito host to determine its likely impact on pathogen transmission as well as its potential ability to invade A. aegypti populations. METHODOLOGY/PRINCIPAL FINDINGS: Here we have examined the probing behavior of Wolbachia-infected mosquitoes in an attempt to understand both the broader impact of Wolbachia infection on mosquito biology and, in particular, vectorial capacity. The probing behavior of wMelPop-infected mosquitoes at four adult ages was examined and compared to uninfected controls during video-recorded feeding trials on a human hand. Wolbachia-positive insects, from 15 days of age, showed a drastic increase in the time spent pre-probing and probing relative to uninfected controls. Two other important features for blood feeding, saliva volume and apyrase content of saliva, were also studied. CONCLUSIONS/SIGNIFICANCE: As A. aegypti infected with wMelPop age, they show increasing difficulty in completing the process of blood feeding effectively and efficiently. Wolbachia-infected mosquitoes on average produced smaller volumes of saliva that still contained the same amount of apyrase activity as uninfected mosquitoes. These effects on blood feeding behavior may reduce vectorial capacity and point to underlying physiological

  6. Incorporated fish oil fatty acids prevent action potential shortening induced by circulating fish oil fatty acids

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    Hester M Den Ruijter

    2010-11-01

    Full Text Available Increased consumption of fatty fish, rich in omega-3 polyunsaturated fatty acids (3-PUFAs reduces the severity and number of arrhythmias. Long term 3-PUFA-intake modulates the activity of several cardiac ion channels leading to cardiac action potential shortening. Circulating 3-PUFAs in the bloodstream and incorporated 3-PUFAs in the cardiac membrane have a different mechanism to shorten the action potential. It is, however, unknown whether circulating 3-PUFAs in the bloodstream enhance or diminish the effects of incorporated 3-PUFAs. In the present study, we address this issue. Rabbits were fed a diet rich in fish oil (3 or sunflower oil (9, as control for 3 weeks. Ventricular myocytes were isolated by enzymatic dissociation and action potentials were measured using the perforated patch clamp technique in the absence and presence of acutely administered 3-PUFAs. Plasma of 3 fed rabbits contained more free eicosapentaenoic acid (EPA and isolated myocytes of 3 fed rabbits contained higher amounts of both EPA and docosahexaenoic acid (DHA in their sarcolemma compared to control. In the absence of acutely administered fatty acids, 3 myocytes had a shorter action potential with a more negative plateau than 9 myocytes. In the 9 myocytes, but not in the 3 myocytes, acute administration of a mixture of EPA+DHA shortened the action potential significantly. From these data we conclude that incorporated 3-PUFAs into the sarcolemma and acutely administered 3 fatty acids do not have a cumulative effect on action potential duration and morphology. As a consequence, patients with a high cardiac 3-PUFA status will probably not benefit from short term 3 supplementation as an antiarrhythmic therapy.

  7. Mid-term clinical outcome of radial shortening for kienbock disease

    Directory of Open Access Journals (Sweden)

    Mohammad H Ebrahimzadeh

    2015-01-01

    Full Text Available Background: To evaluate the intermediate-term outcomes of radius shortening as a treatment for Kienbock′s disease. Materials and Methods: In a historical cohort, 16 skeletally mature patients (9 men and 7 women with Kienbock disease, who were treated with radial shortening osteotomy between 2002 and 2012, were reviewed in our study. The mean age of our patients was 30 (range 18-43 years old. According to Litchman staging, there were 7 wrists at stage II and 9 wrists at stage III (6 at stage IIIA and 3 at stage IIIB. The data of grip strength, pain (visual analog scale (VAS score, wrist range of motion (ROM, ulnar variance (according to Palmer method, and the Lichtman stage were gathered before and after surgery. We evaluated overall wrist function using the Mayo Wrist score and disabilities of the arm shoulder and hand (DASH score before surgery and at the last follow-up. Results: The average of follow-up was 7 years (range from 5 to 9 years. Preoperative ulnar variance was -1.3 mm (range from 2.5 to 1 preoperatively. The mean postoperative ulnar variance was 1 mm positive (range from 0.5 to 1.5. The VAS pain score, the mean arc of wrist flexion and extension, and grip strength improved significantly preoperatively compared to after recovery from surgery. The Lichtman stage was unchanged in nine patients, one grade worse in six patients, and one grade better in one patient. The mean DASH and Mayo scores improved significantly postoperatively compare with preoperation. Comparing preoperative positive, neuter, and negative ulnar variance, there was no significant difference in terms of VAS, DASH, and Mayo scores as well as ROM and grip strength. Conclusion: Our study shows that radius shortening surgery improves pain and disability regardless of ulnar variance.

  8. Telomere longitudinal shortening as a biomarker for dementia status of adults with Down syndrome.

    Science.gov (United States)

    Jenkins, Edmund C; Ye, Lingling; Krinsky-McHale, Sharon J; Zigman, Warren B; Schupf, Nicole; Silverman, Wayne P

    2016-03-01

    Previous studies have suggested that Alzheimer's disease (AD) causes an accelerated shortening of telomeres, the ends of chromosomes consisting of highly conserved TTAGGG repeats that, because of unidirectional 5'-3' DNA synthesis, lose end point material with each cell division. Our own previous work suggested that telomere length of T-lymphocytes might be a remarkably accurate biomarker for "mild cognitive impairment" in adults with Down syndrome (MCI-DS), a population at dramatically high risk for AD. To verify that the progression of cognitive and functional losses due to AD produced this observed telomere shortening, we have now examined sequential changes in telomere length in five individuals with Down syndrome (3F, 2M) as they transitioned from preclinical AD to MCI-DS (N = 4) or dementia (N = 1). As in our previous studies, we used PNA (peptide nucleic acid) probes for telomeres and the chromosome 2 centromere (as an "internal standard" expected to be unaffected by aging or dementia status), with samples from the same individuals now collected prior to and following development of MCI-DS or dementia. Consistent shortening of telomere length was observed over time. Further comparisons with our previous cross-sectional findings indicated that telomere lengths prior to clinical decline were similar to those of other adults with Down syndrome (DS) who have not experienced clinical decline while telomere lengths following transition to MCI-DS or dementia in the current study were comparable to those of other adults with DS who have developed MCI-DS or dementia. Taken together, findings indicate that telomere length has significant promise as a biomarker of clinical progression of AD for adults with DS, and further longitudinal studies of a larger sample of individuals with DS are clearly warranted to validate these findings and determine if and how factors affecting AD risk also influence these measures of telomere length.

  9. Developmental remodeling and shortening of the cardiac outflow tract involves myocyte programmed cell death.

    Science.gov (United States)

    Watanabe, M; Choudhry, A; Berlan, M; Singal, A; Siwik, E; Mohr, S; Fisher, S A

    1998-10-01

    The embryonic outflow tract is a simple tubular structure that connects the single primitive ventricle with the aortic sac and aortic arch arteries. This structure undergoes a complex sequence of morphogenetic processes to become the portion of the heart that aligns the right and left ventricles with the pulmonary artery and aorta. Abnormalities of the outflow tract are involved in many clinically significant congenital cardiac defects; however, the cellular and molecular processes governing the development of this important structure are incompletely understood. Histologic and tissue-tagging studies indicate that the outflow tract tissues compact and are incorporated predominantly into a region of the right ventricle. The hypothesis tested in the current study was that cell death or apoptosis in the muscular portion of the outflow tract is an important cellular mechanism for outflow tract shortening. The tubular outflow tract myocardium was specifically marked by infecting myocytes of the chicken embryo heart with a recombinant replication-defective adenovirus expressing beta-galactosidase (beta-gal) under the control of the cytomegalovirus promoter. Histochemical detection of the beta -gal-labeled outflow tract myocytes revealed that the tubular structure shortened to become a compact ring at the level of the pulmonic infundibulum over several days of development (stages 25-32, embryonic days 4-8). The appearance of apoptotic cardiomyocytes was correlated with OFT shortening by two histologic assays, TUNEL labeling of DNA fragments and AnnexinV binding. The rise and fall in the number of apoptotic myocytes detected by histologic analyses paralleled the change in activity levels of Caspase-3, a protease in the apoptotic cascade, measured in outflow tract homogenates. These results suggest that the elimination of myocytes by programmed cell death is one mechanism by which the outflow tract myocardium remodels to form the proper connection between the ventricular

  10. The effect of brand and caloric information on flavor perception and food consumption in restrained and unrestrained eaters.

    Science.gov (United States)

    Cavanagh, Kevin V; Kruja, Blina; Forestell, Catherine A

    2014-11-01

    The goal of the current study was to determine whether provision of brand and caloric information affects sensory perception and consumption of a food in restrained (n=84) and unrestrained eaters (n=104). Using a between-subjects 2 × 2 × 3 design, female restrained and unrestrained eaters were asked to taste and rate a cookie that was labeled with a brand associated with healthful eating (Kashi(®)) or one associated with unhealthful eating (Nabisco(®)). Additionally, some participants were presented with a nutrition label alongside the brand name indicating that one serving contained 130 calories (Low-Calorie Condition), or 260 calories (High-Calorie Condition). The remaining participants were not shown a nutrition label (No Label Condition). Results indicated that those in the No Label or the High-Calorie Condition perceived the healthful branded cookie to have a better flavor than those who received the unhealthful branded cookie regardless of their restraint status. However, restrained eaters in the No Label Condition consumed more of the healthful than the unhealthful branded cookie, whereas those in the Low-Calorie Condition consumed more of the unhealthful than the healthful branded cookie. In contrast, unrestrained eaters ate more of the healthful branded cookie regardless of the caloric information provided. Thus, although restrained and unrestrained eaters' perceptions are similarly affected by branding and caloric information, brands and caloric information interact to affect restrained eaters' consumption. This study reveals that labeling foods as low calorie may create a halo effect which may lead to over-consumption of these foods in restrained eaters.

  11. Effect of replacing sugar with non-caloric sweeteners in beverages on the reward value after repeated exposure.

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    Sanne Griffioen-Roose

    Full Text Available BACKGROUND: The reward value of food is partly dependent on learned associations. It is not yet known whether replacing sugar with non-caloric sweeteners in food is affecting long-term acceptance. OBJECTIVE: To determine the effect of replacing sugar with non-caloric sweeteners in a nutrient-empty drink (soft drink versus nutrient-rich drink (yoghurt drink on reward value after repeated exposure. DESIGN: We used a randomized crossover design whereby forty subjects (15 men, 25 women with a mean ± SD age of 21 ± 2 y and BMI of 21.5 ± 1.7 kg/m(2 consumed a fixed portion of a non-caloric sweetened (NS and sugar sweetened (SS versions of either a soft drink or a yoghurt drink (counterbalanced for breakfast which were distinguishable by means of colored labels. Each version of a drink was offered 10 times in semi-random order. Before and after conditioning the reward value of the drinks was assessed using behavioral tasks on wanting, liking, and expected satiety. In a subgroup (n=18 fMRI was performed to assess brain reward responses to the drinks. RESULTS: Outcomes of both the behavioral tasks and fMRI showed that conditioning did not affect the reward value of the NS and SS versions of the drinks significantly. Overall, subjects preferred the yoghurt drinks to the soft drinks and the ss drinks to the NS drinks. In addition, they expected the yoghurt drinks to be more satiating, they reduced hunger more, and delayed the first eating episode more. Conditioning did not influence these effects. CONCLUSION: Our study showed that repeated consumption of a non-caloric sweetened beverage, instead of a sugar sweetened version, appears not to result in changes in the reward value. It cannot be ruled out that learned associations between sensory attributes and food satiating capacity which developed preceding the conditioning period, during lifetime, affected the reward value of the drinks.

  12. Effects of fructose-containing caloric sweeteners on resting energy expenditure and energy efficiency: a review of human trials

    OpenAIRE

    Tappy, L; L. Egli; Lecoultre, V.; Schneider, P.

    2013-01-01

    Epidemiological studies indicate that the consumption of fructose-containing caloric sweeteners (FCCS: mainly sucrose and high-fructose corn syrup) is associated with obesity. The hypothesis that FCCS plays a causal role in the development of obesity however implies that they would impair energy balance to a larger extent than other nutrients, either by increasing food intake, or by decreasing energy expenditure. We therefore reviewed the literature comparing a) diet-induced thermogenesis (DI...

  13. Effective shortening of picosecond pulses emitted by a YAG:Nd/sup 3 +/ laser

    Energy Technology Data Exchange (ETDEWEB)

    Dianov, E.M.; Karasik, A.Y.; Mamyshev, P.V.; Onishchukov, G.I.; Prokhorov, A.M.; Stel' makh, M.F.; Fomichev, A.A.

    1984-06-01

    A 15-fold reduction in the duration of YAG:Nd/sup 3 +/ laser pulses was achieved under conditions of active mode locking and Q switching at a pulse repetition frequency approx.1 kHz. Phase self-modulation in a single-mode quartz fiber waveguide of length 10 m resulted in broadening of the laser emission spectrum right up to approx.10 cm/sup -1/ at the waveguide exit. The pulses were then shortened in a system with a diffraction grating. The pulse duration was measured by a correlation system in which the second harmonic was generated.

  14. Lactose tolerance test shortened to 30 minutes: an exploratory study of its feasibility and impact

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    José Luis Domínguez-Jiménez

    2014-06-01

    Full Text Available Introduction: Lactose malabsorption (LM is a very common condition with a high prevalence in our setting. Lactose tolerance test (LTT is a basic, affordable test for diagnosis that requires no complex technology. It has been recently shown that this test can be shortened to 3 measurements (baseline, 30 min, 60 min with no impact on final results. The purpose of our study was to assess the feasibility and benefits of LTT simplification and shortening to 30 min, as well as the financial impact entailed. Material and methods: A multicenter, observational study of consecutive patients undergoing LTT for LM suspicion. Patients received 50 g of lactose following a fasting period of 12 h, and had blood collected from a vein at all 3 time points for the measurement of blood glucose (mg/dl. Differences between the shortened and complete test forms were analyzed using McNemar's test. A comparison of blood glucose levels between patients with normal and abnormal results was performed using Student's T-test for independent mean values. Consistency was assessed using the kappa index. A p < 0.05 was considered to be statistically significant. Results: A total of 270 patients (69.6% females were included, with a mean age of 39.9 ± 16 years. LTT was abnormal for 151 patients (55.9%. We observed no statistically significant differences in baseline blood glucose levels between patients with normal and abnormal LTT results (p = 0.13; however, as was to be expected, such differences were obvious for the remaining time points (p < 0.01. Deleting blood glucose measurements at 60 minutes only led to overdiagnose LM (false positive results in 6 patients (2.22 %, with a kappa index of 0.95 (95% CI: 0.92-0.99 (p < 0.001 versus the complete test. Suppressing measurements at 60 min would have saved at least € 7,726. Conclusion: The shortening of LTT to only 2 measurements (baseline and 30-min hardly leads to any differences in final results, and would entail savings in

  15. [Carotid endarterectomy. Experiences with shortening of interval between symptom and operation

    DEFF Research Database (Denmark)

    Rathenborg, L.K.; Baekgaard, N.; Jensen, Leif Pandora

    2008-01-01

    and in the neurological departments. The stroke and death rate was unchanged, 4% and 3% before and after fast track respectively. CONCLUSION: The time between symptom and CEA can be shortened by means of a fast track after thorough information and reorganization of the work involving these patients. In order to bring......INTRODUCTION: Carotid endarterectomy (CEA) prevents transient ischemic attack and stroke in patients with symptomatic high-grade carotid stenosis. In 2004 Rothwell et al showed that maximal benefit is gained if CEA is performed less than three weeks after the onset of the symptom. With the aim...

  16. Single clear corneal incision for glaucoma drainage device shortening in pediatric glaucoma.

    Science.gov (United States)

    Radke, Phillip M; Bitrian, Elena; Grajewski, Alana L

    2016-06-01

    Glaucoma drainage devices are commonly used for management of glaucoma in adults and children. With time, the position of the tube can change and cause damage such as corneal scarring, iris or lens contact, and uveitis. Most of these problems can be improved with tube shortening and/or excision of adherent iris or fibrous tissue. We describe a surgical technique that uses a single clear corneal incision to externalize and trim the shunt in pediatric patients. The technique has a short surgical. We review the indications and outcomes for this procedure in 13 eyes of 12 children who required shunt revision.

  17. Trombose induzida pelo calor endovenoso: relato de dois casos tratados com rivaroxabana e revisão da literatura

    Directory of Open Access Journals (Sweden)

    Walter Junior Boim de Araujo

    2016-01-01

    Full Text Available Resumo Define-se trombose induzida pelo calor endovenoso como a propagação do trombo a partir de uma veia superficial em direção a uma veia mais profunda. Em geral, é considerada clinicamente insignificante quando não há propagação do trombo para o sistema venoso profundo. Essa condição pode ser tratada com terapia anticoagulante, embora a observação pareça ser suficiente, principalmente para graus menores. Neste estudo, relatamos dois casos de trombose induzida pelo calor endovenoso que teriam indicação de heparina de baixo peso molecular até a resolução do quadro. Porém, optou-se pelo uso da rivaroxabana (15 mg de 12 em 12h, com resolução completa do trombo em 4 semanas (caso 1 e em 7 dias (caso 2. A rivaroxabana pode ser uma alternativa promissora no tratamento da trombose induzida pelo calor endovenoso avançada, pela simplicidade da posologia, sem comprometimento da eficácia ou da segurança. São necessários estudos prospectivos, randomizados e controlados que possibilitem melhor entendimento da condição e o desenvolvimento de recomendações mais definitivas sobre opções de prevenção e tratamento.

  18. Islas de calor urbano en Tampico, México. Impacto del microclima a la calidad del hábitat

    Directory of Open Access Journals (Sweden)

    Carlos Alberto Fuentes Pérez

    2014-01-01

    Full Text Available De todas las modificaciones climáticas por causa urbana, las térmicas son las más conocidas por los propios ciudadanos. La acción transformadora del espacio natural sobre el que se realiza el emplazamiento de la ciudad, llega a ser productora en gran medida de sus condiciones ambientales, incluida la climatología urbana. Todo proceso de urbanización sustituye los suelos y áreas naturales por superficies construidas, cuyos materiales se caracterizan por una baja reflectividad, con disminución de la capacidad de absorción de agua y un comportamiento térmico propicio para el almacenamiento y la emisión de calor. Estos elementos coadyuvan a realzar la temperatura atmosférica de la ciudad en relación con su entorno menos urbanizado a través de un fenómeno conocido como efecto de islas de calor urbano, produciendo un impacto del microclima a la calidad del hábitat. La presente investigación experimental aplicada tiene como objetivo, demostrar la metodología de investigación adoptada, para realizar las islas de calor urbanas en Tampico, México.

  19. General and persistent effects of high-intensity sweeteners on body weight gain and caloric compensation in rats.

    Science.gov (United States)

    Swithers, Susan E; Baker, Chelsea R; Davidson, T L

    2009-08-01

    In an earlier work (S. E. Swithers & T. L. Davidson, 2008), rats provided with a fixed amount of a yogurt diet mixed with saccharin gained more weight and showed impaired caloric compensation relative to rats given the same amount of yogurt mixed with glucose. The present 4 experiments examined the generality of these findings and demonstrated that increased body weight gain was also demonstrated when animals consumed a yogurt diet sweetened with an alternative high-intensity sweetener (acesulfame potassium; AceK) as well as in animals given a saccharin-sweetened base diet (refried beans) that was calorically similar but nutritionally distinct from low-fat yogurt. These studies also extended earlier findings by showing that body weight differences persist after saccharin-sweetened diets are discontinued and following a shift to a diet sweetened with glucose. In addition, rats first exposed to a diet sweetened with glucose still gain additional weight when subsequently exposed to a saccharin-sweetened diet. The results of these experiments add support to the hypothesis that exposure to weak or nonpredictive relationships between sweet tastes and caloric consequences may lead to positive energy balance.

  20. PROCEDIMIENTO DE CALIBRACIÓN EN TEMPERATURA Y FLUJO DE CALOR DE UN CALORÍMETRO DIFERENCIAL DE BARRIDO (DSC

    Directory of Open Access Journals (Sweden)

    Pablo E. Reynoso

    2016-01-01

    Full Text Available El calorímetro diferencial de barrido no es un dispositivo de medición absoluta, por lo que su utilización requiere indispensable mente una calibración. En esta contribución se presenta un procedimiento de calibración para el cual s e consideraron las temperaturas y calores de fusión aceptados en la literatura de 5 materiales puros . S e prepararon 6 muestras de dife rentes masas para cada material y s e sometió cada una de ellas a ci clos de calentamiento , desde temperatura ambiente hasta 50 ºC por encima de las temperaturas de fusión , utilizando 6 velocidades distintas por cada probeta. Luego, p ara determinar una relación de ajuste entre los datos experimentales obtenidos y los valores aceptados , se utilizó un método de regresión no lineal mediante un procedimiento matricial desarrollado en el entorno MATLAB . Los resultados obtenidos muestran una corrección con una desviación estándar de 1,2 ºC para el ajuste en temperatura y 2,1 5 J/g para el flujo de calor.

  1. Caloric Intake on the Sabbath: A Pilot Study of Contributing Factors to Obesity in the Orthodox Jewish Community.

    Science.gov (United States)

    Rosenberg, Deborah A; Swencionis, Charles; Segal-Isaacson, C J

    2016-10-01

    The American Orthodox Jewish community has specific cultural factors that may contribute to overweight and obesity. This study aimed to look at caloric intake on the Sabbath and its contribution to overweight and obesity. Twelve married or previously married women who identify themselves as Orthodox Jews were recruited to do 24-h food recalls over the phone. The participants were divided into three weight groups (normal, overweight, and obese) based on their BMI. The overweight and obese participants' data were combined into one group for the purposes of statistical testing. Paired t tests looking at the data for all participants showed significantly great caloric intake during an average Sabbath day than an average weekday [t(4) = 7.58, p Sabbath for the overweight-obese women compared to the normal weight women [F(1) = 7.83, p = 0.02]. No statistical difference was seen between the weekday energy intake of the normal weight women as compared to the combined group of overweight-obese women [F(1) = 0.501, p = 0.499]. These results support the hypotheses that all groups eat significantly more on the Sabbath than on weekdays, and overweight and obese individuals eat significantly more on the Sabbath than normal weight individuals. This supports the theory that caloric intake on the Sabbath is a contributing factor to overweight and obesity within the American Orthodox Jewish community.

  2. Nonnutritive, Low Caloric Substitutes for Food Sugars: Clinical Implications for Addressing the Incidence of Dental Caries and Overweight/Obesity

    Directory of Open Access Journals (Sweden)

    Michael W. Roberts

    2012-01-01

    Full Text Available Caries and obesity are two common conditions affecting children in the United States and other developed countries. Caries in the teeth of susceptible children have often been associated with frequent ingestion of fermentable sugars such as sucrose, fructose, glucose, and maltose. Increased calorie intake associated with sugars and carbohydrates, especially when associated with physical inactivity, has been implicated in childhood obesity. Fortunately, nonnutritive artificial alternatives and non-/low-caloric natural sugars have been developed as alternatives to fermentable sugars and have shown promise in partially addressing these health issues. Diet counseling is an important adjunct to oral health instruction. Although there are only five artificial sweeteners that have been approved as food additives by the Food and Drug Administration (FDA, there are additional five non-/low caloric sweeteners that have FDA GRAS (Generally Recognized as Safe designation. Given the health impact of sugars and other carbohydrates, dental professionals should be aware of the nonnutritive non-/low caloric sweeteners available on the market and both their benefits and potential risks. Dental health professionals should also be proactive in helping identify patients at risk for obesity and provide counseling and referral when appropriate.

  3. Evaluation of dysphagia risk, nutritional status and caloric intake in elderly patients with Alzheimer's

    Directory of Open Access Journals (Sweden)

    Vanessa Fernanda Goes

    2014-04-01

    Full Text Available OBJECTIVE: to evaluate the risk of dysphagia and its relationship with the stage of Alzheimer's Disease, as well as the relationship between the risk of dysphagia and nutritional status and caloric intake in elderly people with Alzheimer's disease.METHODS: the sample consisted of 30 subjects of both genders with probable Alzheimer's disease. The stage of the disease, nutritional status, energy intake, and risk of dysphagia were assessed.RESULTS: it was found that increased risk of dysphagia is associated with the advance in the stages of Alzheimer's disease and that even patients in the early stages of disease have a slight risk of developing dysphagia. No association was found between nutritional status and the risk of dysphagia. High levels of inadequate intake of micronutrients were also verified in the patients.CONCLUSION: an association between dysphagia and the development of Alzheimer's disease was found. The results indicate the need to monitor the presence of dysphagia and the micronutrient intake in patients with Alzheimer's disease.

  4. Non-Invasive Neuromodulation Using Time-Varying Caloric Vestibular Stimulation

    Science.gov (United States)

    Rogers, Lesco L.; Ade, Kristen K.; Nicoletto, Heather A.; Adkins, Heather D.; Laskowitz, Daniel T.

    2016-01-01

    Caloric vestibular stimulation (CVS) to elicit the vestibulo-ocular reflex has long been used in clinical settings to aid in the diagnosis of balance disorders and to confirm the absence of brainstem function. While a number of studies have hinted at the potential therapeutic applications of CVS, the limitations of existing devices have frustrated that potential. Current CVS irrigators use water or air during short-duration applications; however, this approach is not tenable for longer duration therapeutic protocols or home use. Here, we describe a solid-state CVS device we developed in order to address these limitations. This device delivers tightly controlled time-varying thermal waveforms, which can be programmed through an external control unit. It contains several safety features, which limit patients to the prescribed waveform and prevent the potential for temperature extremes. In this paper, we provide evidence that CVS treatment with time-varying, but not constant temperature waveforms, elicits changes in cerebral blood flow physiology consistent with the neuromodulation of brainstem centers, and we present results from a small pilot study, which demonstrate that the CVS can safely and feasibly be used longitudinally in the home setting to treat episodic migraine. Together, these results indicate that this solid-state CVS device may be a viable tool for non-invasive neuromodulation. PMID:27777829

  5. Calor: Una Propuesta Didáctica Constructivista con Enfoque de Ciencia Integrada

    Directory of Open Access Journals (Sweden)

    Castillo Alberto de L.

    2002-01-01

    Full Text Available Realizamos un estudio comparativo entre dos diseños didácticos constructivistas para la enseñanza del tema Calor en estudiantes de carreras en ciencias naturales. Uno con un enfoque de ciencia integrada y el otro con un enfoque no integrador. En el primer diseño el alumno construye su propio conocimiento resolviendo situaciones problemáticas relacionadas a la biología y el medio-ambiente, que le permite analizar y relacionar los conceptos involucrados, mientras que en el segundo construye su conocimiento a través de la resolución de situaciones problemáicas físicas pero no biológicas. Concluimos que el primer diseño favorece en los alumnos la construcción de una estructura cognitiva del tipo integrada, que les facilita internalizar y transferir los conceptos físicos a problemas concretos de su especialidad.

  6. Efficient gasification of wet biomass residue to produce middle caloric gas

    Institute of Scientific and Technical Information of China (English)

    Guangwen Xu; Takahiro Murakami; Toshiyuki Suda; Hidehisa Tani; Yutaka Mito

    2008-01-01

    Various process residues represent a kind of biomass resource already concentrated but containing water as much as 60 wt.%.These materials are generally treated as waste or simply combusted directly to generate heat.Recently,we attempted to convert them into middle caloric gas to substitute for natural gas,as a chemical or a high-rank gaseous fuel for advanced combustion utilities.Such conversion is implemented through dual fluidized bed gasification (DFBG).Concerning the high water content of the fuels,DFBG was suggested to accomplish either with high-efficiency fuel drying in advance or direct decoupling of fuel drying/pyrolysis from char gasification and tar/hydrocarbon reforming.Along with fuel drying,calcium-based catalyst can be impregnated into the fuel,without much additional cost,to increase the fuel's gasification reactivity and to reduce tar formation.This article reports the Ca impregnation method and its resulting effects on gasification reactivity and tar suppression ability.Meanwhile,the principle of directly gasifying wet fuel with decoupled dual fluidized bed gasification (D-DFBG) is also highlighted.

  7. Transferencia de calor en la colada continua de aceros. II parte. Enfriamiento secundario

    Directory of Open Access Journals (Sweden)

    Cicutti, C.

    1997-12-01

    Full Text Available Once the strand leaves the mold, the solidification of steel progresses due to the heat extracted in the secondary cooling zone of the continuous casting machine. In this zone, heat is extracted mainly by: the incidence of water from sprays, radiation to surroundings contact with rolls and run out water accumulated between rolls and strand. In this work, all these mechanisms are evaluated and, when it is possible, they are quantified. Methods which are usually employed to measure solidification profiles in the continuous casting machine are also reviewed. Finally, the incidence of secondary cooling on the quality of cast products is discussed.

    La solidificación del acero iniciada en el molde continúa en la zona de enfriamiento secundario de la máquina donde el calor es extraído, principalmente por la incidencia del agua de los rociadores, la radiación al medio ambiente, el contacto con los rodillos y el agua acumulada en ellos. En este trabajo se revisa cada uno de estos mecanismos determinando, en los casos en que es posible, valores cuantitativos de los mismos. Además, se analizan los distintos métodos empleados para medir el avance del espesor solidificado en la máquina de colada continua. Por último, se discute la incidencia del enfriamiento secundario en la calidad final de los productos colados.

  8. Historical evolution of slope instability in the Calore River Basin, Southern Italy

    Science.gov (United States)

    Diodato, Nazzareno; Soriano, Marcella; Bellocchi, Gianni; Fiorillo, Francesco; Cevasco, Andrea; Revellino, Paola; Guadagno, Francesco Maria

    2017-04-01

    There is interest in knowing historical spatio-temporal patterns of landslide activity. However, this is challenging to reconstruct because it is difficult to obtain detailed records for past landslide activity. Here, we deal with hydro-geomorphological signatures, such as storms, downpours, floods, snowmelt and mass movement, to detect annual slope instability events (ASIEs) over historical times. In order to obtain ASIEs for each year, a monthly Instability Density Index (IDI) was used and then monthly values were summed up to obtain a yearly value. Classes of monthly IDI varying between 0 (no instability) and 4 (highest instability) were determined from historical documents. We present an application for the Calore River Basin, Southern Italy, using data from a 313-year long series (1701-2013 CE). After 1880 CE the information becomes more valuable with directly observed landslide frequency. By this cataloguing, 129 ASIEs were obtained. Their evolution shows slight instability during the 18th century. Uneven and greater slope instability occurred instead across the 19th century, when an important phase of deforestation coincided with intensification of agricultural activities. Slope instability events continued during the 20th century but their causes are mainly related to anthropisation and the effects of recent climate change. It was determined that stormy autumns until the 19th century and successive winter-times with enhanced snowmelt, may have driven the reactivation of widespread instability events. We also found that mountainous and hilly terrains have an acute sensitivity to climate change.

  9. Artigos esterilizados em calor úmido: validação do sistema de guarda

    Directory of Open Access Journals (Sweden)

    Zilah Cândida Pereira das Neves

    2004-04-01

    Full Text Available Objetivamos identificar o tempo de validade da esterilização dos artigos processados pelo calor úmido, considerando as condições de esterilização e guarda. A validação deu-se através de testes microbiológicos realizados com instrumentais processados numa mesma carga e avaliados em tempos 0, 7, 10, 15 e 25 dias. Foram analisados 30% do instrumental de cada pacote que foi colocado em caldo Mueller Hinton e incubado a 37ºC por 72 horas. A leitura deu-se pela turvação do caldo. Das amostras avaliadas de nove cargas, em nenhuma houve crescimento microbiológico. Concluiu-se que apesar das condições de esterilização e guarda do material não se adequarem totalmente dentro dos parâmetros recomendados pela literatura, a esterilização ocorreu e manteve-se por um período de 25 dias.

  10. Practical system for the direct measurement of magneto-caloric effect by micro-thermocouples.

    Science.gov (United States)

    Kamarád, J; Kaštil, J; Arnold, Z

    2012-08-01

    A system for direct measurements of the magneto-caloric effect (MCE) exploits a rapid transport of a sample into or from magnetic field in permanent Halbach-type (1 T) or superconducting (4.7 T) magnets. Time dependence of induced changes of the sample temperature, ΔT(t), is detected directly by the differential Cu-Constantan-Cu micro-thermocouples with time steps of 300 ms. A sample placed inside an evacuated simple LN(2) cryostat is either totally isolated (adiabatic conditions) or partly connected with the copper sample holder (non-adiabatic conditions). The last arrangement (a model of the Brayton cycle) is used to simulate an application of MCE in refrigeration techniques. The relations describing ΔT(t) that allow an analysis of MCE of the studied materials are based on the general cooling law. The effect of the first-order magnetic transition on MCE of selected sample is also demonstrated by non-standard ΔT(t) curves measured in the last mentioned experimental arrangements.

  11. The effects of caloric stimulation of the labyrinth on the soleus motor pool in man.

    Science.gov (United States)

    Delwaide, P J; Juprelle, M

    1977-04-01

    The effects of caloric stimulation of the labyrinth on the soleus motor pool have been investigated using the Achilles tendon reflex, the H reflex, and the vibratory inhibition of the H reflex. The excitability of the myotatic reflex are is augmented from the beginning of irrigation and remains so until the end of nystagmus. The effects are bilateral and roughly symmetrical. The observed effects are due to simultaneous activation of non-specific, probably reticular, and specific, doubtless vestibular, , mechanisms. The Achilles tendon reflex is more facilitated than the H reflex, and the vibratory inhibition of the H reflex is not modified following irrigation of the ear canal. These results indicate a simultaneous facilitation of alpha and gamma extensor motoneurones but gamma effects clearly predominate. This interpretation is in good agreement with the findings of the animal neurophysiology. The vibratory inhibition argues against a modification of presynaptic inhibition. Before interpreting this fact as different from animal mechanisms, one must take into account the particular experimental conditions realized in man: the stimulus is complex and interactions between various nervous structures are possible.

  12. Molecular motion in restricted geometries

    Indian Academy of Sciences (India)

    Siddharth Gautam; S Mitra; R Mukhopadhyay

    2008-10-01

    Molecular dynamics in restricted geometries is known to exhibit anomalous behaviour. Diffusion, translational or rotational, of molecules is altered significantly on confinement in restricted geometries. Quasielastic neutron scattering (QENS) offers a unique possibility of studying molecular motion in such systems. Both time scales involved in the motion and the geometry of motion can be studied using QENS. Molecular dynamics (MD) simulation not only provides insight into the details of the different types of motion possible but also does not suffer limitations of the experimental set-up. Here we report the effect of confinement on molecular dynamics in various restricted geometries as studied by QENS and MD simulations: An example where the QENS technique provided direct evidence of phase transition associated with change in the dynamical behaviour of the molecules is also discussed.

  13. The effect of strength training, recreational soccer and running exercise on stretch-shortening cycle muscle performance during countermovement jumping

    DEFF Research Database (Denmark)

    Jakobsen, Markus Due; Sundstrup, Emil; Randers, Morten Bredsgaard

    2012-01-01

    The purpose of the present study was to evaluate the effect of contrasting training modalities on mechanical muscle performance and neuromuscular activity during maximal SSC (stretch-shortening cycle) countermovement jumps (CMJ). Bilateral countermovement jumping, surface electromyography (EMG...

  14. Two-stage revision of infected hip arthroplasty using a shortened post-operative course of antibiotics.

    LENUS (Irish Health Repository)

    McKenna, Paul B

    2009-04-01

    We present a series of 30 consecutive patients with 31 infected total hip arthroplasties treated by a single surgeon over a 4-year period in whom a shortened post-operative course of antimicrobial chemotherapy was used.

  15. In-treatment midwall and endocardial fractional shortening predict cardiovascular outcome in hypertensive patients with preserved baseline systolic ventricular function: the Losartan Intervention For Endpoint reduction study

    DEFF Research Database (Denmark)

    Wachtell, Kristian; Gerdts, Eva; Palmieri, Vittorio;

    2010-01-01

    Endocardial fractional shortening (EFS) and midwall shortening (MWS) are impaired in patients with left ventricular hypertrophy. However, it remains unknown whether improvement of left ventricular systolic function during treatment reduces cardiovascular morbidity and mortality in hypertensive pa...

  16. Temperature jump induced force generation in rabbit muscle fibres gets faster with shortening and shows a biphasic dependence on velocity.

    Science.gov (United States)

    Ranatunga, K W; Roots, H; Offer, G W

    2010-02-01

    We examined the tension responses to ramp shortening and rapid temperature jump (muscle fibres at 8-9 degrees C (the fibre length (L(0)) was approximately 1.5 mm and sarcomere length 2.5 microm). The aim was to investigate the strain sensitivity of crossbridge force generation in muscle. The T-jump induced tension rise was examined during steady shortening over a wide range of velocities (V) approaching the V(max) (V range approximately 0.01 to approximately 1.5 L(0) s(1)). In the isometric state, a T-jump induced a biphasic tension rise consisting of a fast (approximately 50 s(1), phase 2b) and a slow (approximately 10 s(1), phase 3) component, but if treated as monophasic the rate was approximately 20 s(1). During steady shortening the T-jump tension rise was monophasic; the rate of tension rise increased linearly with shortening velocity, and near V(max) it was approximately 200 s(1), approximately 10x faster than in the isometric state. Relative to the tension reached after the T-jump, the amplitude increased with shortening velocity, and near V(max) it was 4x larger than in the isometric state. Thus, the temperature sensitivity of muscle force is markedly increased with velocity during steady shortening, as found in steady state experiments. The rate of tension decline during ramp shortening also increased markedly with increase of velocity. The absolute amplitude of T-jump tension rise was larger than that in the isometric state at the low velocities (shortening velocity is increased, probably enhancement of crossbridge force generation and faster (post-stroke) crossbridge detachment by negative strain. Overall, our results show that T-jump force generation is strain sensitive and becomes considerably faster when exposed to negative strain. Thus the crossbridge force generation step in muscle is both temperature sensitive (endothermic) and strain sensitive.

  17. Shortening spinal column reconstruction through posterior only approach for the treatment of unstable osteoporotic burst lumber fracture: a case report

    OpenAIRE

    Shawky, Ahmed; Kroeber, Markus

    2012-01-01

    Study design Case report. Clinical question This study reports if shortening reconstruction procedure through posterior approach only can be used in osteoporotic unstable fracture as well as post-traumatic burst fracture. Methods An 80-year-old female patient with unstable burst osteoporotic fracture of L1 underwent posterior approach corpectomy and shortening reconstruction of the spinal column by non-expandable cages. Result The surgery was uneventful, with average blood loss. Using of smal...

  18. Changes in the maximum speed of shortening of frog muscle fibres early in a tetanic contraction and during relaxation.

    Science.gov (United States)

    Josephson, R K; Edman, K A

    1998-03-01

    1. Isotonic shortening velocities at very light loads were examined in single fibres of the anterior tibialis muscle of the frog, Rana temporaria, using load-clamp recording and slack tests (temperature, 1-3 degrees C; initial sarcomere length, 2.25 microns). 2. Shortening velocities at very light loads (force-clamp recording) were found to be higher early in the rise of a tetanic contraction than during the plateau of the contraction. The upper limit of the load at which there was elevated shortening velocity early in the contraction was 1.5-5.4% of the maximum tetanic tension (Fo) depending on the particular fibre. 3. The maximum shortening velocity determined using the slack test method (Vo) was as much as 30% greater early in a contraction than at the tetanic plateau. Vo was elevated above the plateau level up to about 30 ms after the end of the latent period, which is equivalent to the time required for the force in an isometric contraction to rise to about 30% of Fo. Vo is depressed below the plateau value during relaxation at the cessation of stimulation. 4. Stimulation studies show that the cross-bridge model of Huxley (1957) predicts the maximum shortening velocity to be greater early in a contraction, when new actin binding sites are becoming activated and new cross-bridge connections are being formed rapidly, than during steady-state contraction. The elevated shortening velocity in the model is a consequence of new cross-bridges being formed in the pulling configuration, and there being a delay before the newly added bridges are dragged beyond their equilibrium position so they begin to retard shortening. The model also predicts that maximum shortening velocity should be depressed below the plateau level during early relaxation as cross-bridge binding sites are rapidly removed from the active population.

  19. Variability in New Shortening Estimates from Southern Peru (12-14S); Implications for Mass Balance of the Andean Plateau.

    Science.gov (United States)

    Gotberg, N.; McQuarrie, N.

    2008-12-01

    One of the fundamental questions of interest with regards to the Andean Plateau is the mass balance of material needed to create and sustain a 3-4 km high plateau. Is crustal shortening sufficient to support an isostatically compensated crust of 60-70km? We present new estimates of shortening across the northern margin of the Andean Plateau. The cross section extent, from the eastern edge of the volcanic arc to foreland basin, is approximately one half of the physiographic width of the Andean Plateau in Peru. Cross sectional shortening estimates in southern Peru (12-14°S) provide a best estimate of 123 km or 40% shortening with an absolute minimum estimate of 86 km or 30% and absolute maximum estimate of 275 km or 60%. We determined the maximum and minimum shortening estimates using the cross sectional area and possible variations in assumptions made about the amount of erosion, detachment dip, involvement of basement thrusts and displacement along faults. The best estimate of shortening is well short of the required 240-300km of shortening needed in order to account for a 60-70km thick crust under the entire plateau. This suggests that for an isostatically equilibrated crust either 1) there is a significant amount of shortening (~150km) in the western half of the plateau which, is hidden by the volcanic arc or 2) crustal material is being added to the Peruvian section of the Andean Plateau either through lower crustal flow or a process of magmatic underplating followed by differentiation and delamination.

  20. Comparison of hydrogenated vegetable shortening and nutritionally complete high fat diet on limited access-binge behavior in rats

    OpenAIRE

    Davis, Jon F.; Melhorn, Susan J; Heiman, Justin U.; Tschöp, Matthias H.; Clegg, Deborah J.; Benoit, Stephen C.

    2007-01-01

    Previous studies have suggested that intermittent exposure to hydrogenated vegetable shortening yields a binge/compensate pattern of feeding in rats. The present study was designed to assess whether rats would exhibit similar patterns of intake when given intermittent access to a nutritionally complete high-fat diet. Four groups of rats received varying exposure to either hydrogenated vegetable shortening or high-fat diet for 8 consecutive weeks. Animals were given daily and intermittent acce...