Search Results
Results 151 - 200 of 711
1 2 3 4 5 6 7 8 9 10 >
dos Reis Flavia C G - - 2006
Papain-like cysteine proteases are important for the survival of the flagellated protozoa Trypanosoma cruzi, the causative agent of Chagas' Disease. The lysosomal cysteine protease designated as cruzipain or cruzain, is the archetype of a multigene family of related isoforms. We investigated the substrate specificity of the cruzipain 2 isoform using ...
Holliday Robin - - 2006
Some animals live in environments in which the food supply fluctuates. When it is scarce these animals do not breed, but invest resources into survival until food is again available, and they can reproduce. Under these circumstances the lifespan can be increased, just as it is after calorie restriction. Other ...
Toporcov Tatiana Natasha - - 2006
Oral squamous cell carcinoma and its treatment are associated with facial disfigurement and functional inabilities that can lead patients to restrict food intake. The current study examined 80 patients undergoing treatment for the disease in a large Brazilian hospital setting, aiming at the appraisal of covariates with prognostic value for ...
Luna-Moreno Dalia - - 2007
Restricted access to food (from 12:00 to 14:00 h) produces a behavioral activation known as food anticipatory activity (FAA), which is a manifestation of the food entrained oscillator (FEO). Peripheral oscillators, especially in the liver, are thought to be part of the FEO. A variety of metabolic adaptations have been ...
Ostrowski Stephane - - 2006
To test the hypothesis that desert ungulates adjust their physiology in response to long-term food and water restriction, we established three groups of sand gazelles (Gazella subgutturosa): one that was provided food and water (n = 6; CTRL) ad lib. for 4 mo, one that received ad lib. food and ...
Gelegen Cigdem - - 2006
Food restriction paradigms are widely used in animal studies to investigate systems involved in energy regulation. We have observed behavioral, physiological, and molecular differences in response to food restriction in three inbred mouse strains, C57BL/6J, A/J, and DBA/2J. These are the progenitors of chromosome substitution and recombinant inbred mouse strains ...
Blom Wendy A M - - 2006
OBJECTIVE: To study the role of ghrelin as a hunger signal during energy restriction and to test the hypothesis that changes in fasting leptin concentrations during energy restriction are associated with changes in fasting ghrelin concentrations. RESEARCH METHODS AND PROCEDURES: Thirty-five healthy, lean men (23 +/- 3 years of age; ...
Cresswell Thomas - - 2006
In 2001, legislative measures were introduced in the UK to restrict usage of antifouling agents in small (<25 m) vessel paints to dichlofluanid, zinc pyrithione and zineb. This removed the previously popular booster biocides diuron and Irgarol 1051 from the market. To investigate the impact of this legislation, water samples ...
Zhen Juan - - 2006
The present communication reports on DA uptake in rat striatum in a model of chronic food restriction. The K(m) for DA uptake was unaltered, but the V(max) was reduced by 32%, not supporting the idea that the enhanced behavioral sensitivity to cocaine or d-amphetamine upon chronic food restriction is due ...
Gooley Joshua J - - 2006
Circadian rhythms of behavior and physiology can be entrained by daily cycles of restricted food availability, but the pathways that mediate food entrainment are unknown. The dorsomedial hypothalamic nucleus (DMH) is critical for the expression of circadian rhythms and receives input from systems that monitor food availability. Here we report ...
Valenzano Dario R - - 2006
Resveratrol, a natural phytoalexin found in grapes and red wine, increases longevity in the short-lived invertebrates Caenorhabditis elegans and Drosophila and exerts a variety of biological effects in vertebrates, including protection from ischemia and neurotoxicity. Its effects on vertebrate lifespan were not yet known. The relatively long lifespan of mice, ...
Lindblom Jonas - - 2006
Dieting as a strategy to reduce body weight often fails as it causes food cravings leading to bingeing and weight regain. Evidence from several lines of research suggests the presence of shared elements for neural regulation of food and drug craving. We quantified the expression of eight genes involved in ...
Masoro Edward J - - 2006
It has long been held that food restriction extends the life span of rodents and other species by decreasing caloric intake and slowing the rate of aging. Recent findings challenge these concepts. This review assesses these controversial issues. The conclusion is that caloric restriction underlies the life extension of rats, ...
Amen-Ra Nūn - - 2006
Humans are evolutionarily adapted to chronic undernutrition as a consequence of ecologically dictated dietary restriction. Increased aridity, cooler temperatures and increased climatic oscillation effected an alteration of the quantity and quality of vegetation upon which hominids depended for food during the Plio-Pleistocene period. Hominids responded physiologically to climate-induced caloric curtailment ...
Ramkumar K M - - 2006
Food restriction, although long popular among gerontologists, has emerged as a new challenge in public health in postindustrial societies because this is the only intervention that repeatedly and strikingly increases maximum life span. The practice of food restriction is widespread for cosmetic, health, and economic reasons. The beneficial effects and ...
Laugen Ane T - - 2005
The degree to which genetic variation in a given trait varies among different populations of the same species and across different environments has seldom been quantified in wild vertebrate species. We investigated the expression of genetic variability and maternal effects in three larval life-history traits of the amphibian Rana temporaria. ...
Ventura Rossella R Dipartimento di Psicologia, Università "La Sapienza," and Fondazione Santa Lucia IRCCS, Rome, Italy. - - 2005
Environmental condition such as food restriction has been shown to produce sensitization to the stimulant and rewarding effects of amphetamine in the low responsive DBA/2J genotype. Here, we report that food-restricted DBA/2J mice lose the impulse-independent component of psychostimulant-induced dopamine release in the nucleus accumbens that is replaced totally by ...
Gutman Roee - - 2006
Golden spiny mice, which inhabit rocky deserts and do not store food, must therefore employ physiological means to cope with periods of food shortage. Here we studied the physiological means used by golden spiny mice for conserving energy during food restriction and refeeding and the mechanism by which food consumption ...
Ostrowski Stéphane - - 2006
Desert mammals often experience scarcity of drinking water and food for prolonged periods. In this study, the first long-term acclimation experiment in a non-domesticated desert-adapted ungulate, we investigated the mechanisms used by the Arabian oryx Oryx leucoryx, to adjust its physiology to progressive food and water restriction over 5 months, ...
Carvalho Gil B GB Division of Biology 156-29, California Institute of Technology, Pasadena, California 91125, - - 2005
Dietary restriction extends the lifespan of numerous, evolutionarily diverse species. In D. melanogaster, a prominent model for research on the interaction between nutrition and longevity, dietary restriction is typically based on medium dilution, with possible compensatory ingestion commonly being neglected. Possible problems with this approach are revealed by using a ...
Roman E A - - 2005
The aims of this study were to investigate the effects of chronic feed deprivation on the ovulatory process, and to assess whether leptin administration is able to alter these effects. Prepuberal rats subjected to food restriction and primed with gonadotrophins were used. Body and ovarian weights were significantly decreased in ...
Barbano M Flavia - - 2005
The authors investigated the role of food incentive properties and homeostatic state on the motivational, anticipatory, and consummatory aspects of feeding. Behavioral tests were carried out on food-sated and food-restricted rats that were presented with 2 kinds of food differing in their palatability level. Both food-sated and food-restricted rats consumed ...
Kirkwood Thomas B L - - 2005
The food restriction model for life extension is nearing "three-score and 10" years of age and remains in good shape, preserving much of the mystique of its youth. Although originally described for laboratory rodents, recent work shows that food restriction also appears to slow ageing processes in a range of ...
Partridge Linda - - 2005
The fruit fly Drosophila is a useful organism for the investigation of the mechanisms by which dietary restriction (DR) extends lifespan. Its relatively short generation time, well-characterised molecular biology, genetics and physiology and ease of handling for demographic analysis are all major strengths. Lifespan has been extended by DR applied ...
Desai Mina - - 2005
OBJECTIVE: We studied the impact of maternal water-restriction during rat pregnancy on newborn plasma composition, and determined the persistence of plasma composition alterations in adult offspring. METHODS: Maternal dams were water-restricted from 10 days of pregnancy until term (21 days) and throughout lactation to increase plasma sodium levels by approximately ...
Desai Mina - - 2005
OBJECTIVE: Maternal undernutrition affects fetal growth and development. We investigated whether maternal food restriction during pregnancy and/or lactation permanently alters organ growth among adult offspring. STUDY DESIGN: From 10 days to term gestation and through 21 days lactation, control pregnant rats received ad libitum food, whereas study rats were 50% ...
Piper Matthew D W - - 2005
Dietary restriction (DR) by dilution of the food medium can extend lifespan in Drosophila. DR results in a state that is characterized by reduced fecundity, increased starvation resistance and higher total lipid levels. In the past, each of these correlated phenotypes has been proposed to play a causal role in ...
Pravosudov Vladimir V - - 2006
Altricial birds grow rapidly during post-hatching period and are developmentally sensitive to variations in food supply. Limited food results in elevated corticosterone levels in chicks of semi-precocial birds but it is not clear whether altricial songbirds show similar adrenocortical stress response to nutritional restrictions during early development. It is also ...
Smith Lori K - - 2005
A number of standard behavioral tasks in animal research utilize food rewards for positive reinforcement. In order to enhance the motivation to participate in these tasks, animals are usually placed on a restricted diet. While dietary restriction (DR) has been shown to have beneficial effects on recovery after brain injury, ...
Nguyen N H - - 2005
Residual feed intake (RFI) represents the deviation of the actual ad libitum food consumption of each animal from that predicted from combination of growth rate, backfat and metabolic body weight measurements. After 4 years of divergent selection of pigs in lines for either high or low postweaning growth rate on ...
Smith James C JC - - 2005
Droperidol has been an efficacious, inexpensive butyrophenone used since the early 1970s to prevent or treat postoperative nausea and vomiting. Because of reports of sudden cardiac death in patients receiving droperidol, the US Food and Drug Administration (FDA) recently placed significant restrictions on its administration. These restrictions have essentially removed ...
Barbarich-Marsteller Nicole C - - 2005
Anorexia nervosa is a life-threatening psychiatric disorder characterized by severe weight loss and high rates of comorbidity and mortality. The current study assessed the feasibility of using microPET imaging to study the effects of chronic food restriction in an animal model of anorexia nervosa. To establish preliminary support for this ...
Langley-Evans Simon C - - 2005
Epidemiological observations of associations between early life nutrition and long-term disease risk have prompted detailed experimental investigation of the biological basis of programming. Studies using rodent or large animal models have clearly established the biological plausibility of nutritional programming and are now yielding important information on underlying mechanisms. Nutritional interventions ...
Báez-Ruiz Adrián - - 2005
Food anticipatory activity (FAA) is an output of the food-entrained oscillator (FEO), a conspicuous biological clock that expresses when experimental animals are under a restricted food schedule (RFS). We have shown that the liver is entrained by RFS and exhibits an anticipatory response before meal time in its oxidative and ...
Mair William - - 2005
Dietary restriction (DR) extends life span in diverse organisms, including mammals, and common mechanisms may be at work. DR is often known as calorie restriction, because it has been suggested that reduction of calories, rather than of particular nutrients in the diet, mediates extension of life span in rodents. We ...
Piper Matthew D W - - 2005
Reduction of food intake without malnourishment extends life span in many different organisms. The majority of work in this field has been performed in rodents where it has been shown that both restricting access to the entire diet and restricting individual dietary components can cause life-span extension. Thus, for insights ...
Kitaysky Alexander S - - 2005
In several seabirds, nutritional state of a nest-bound chick is negatively correlated with the activity of its hypothalamus-pituitary-adrenal (HPA) axis. Increased corticosterone (cort) secretion has been shown to facilitate changes in behavior that allow hungry chicks to obtain more food from parents. However, if parents are not willing/able to buffer ...
Belda Xavier - - 2005
Partial food restriction (FR) protocols have been used not only to study behavioral and physiological consequences of decrease food intake, but as a necessary treatment of the animals in some operant learning tasks. It is well-established in rodents that restricting food availability to a few hours in the morning causes ...
Ehrhardt N - - 2005
The golden spiny mouse (Acomys russatus) is an omnivorous desert rodent that does not store food, but can store large amounts of body fat. Thus, it provides a good animal model to study physiological and behavioural adaptations to changes in food availability. The aim of this study was to investigate ...
Nguyen Nguyen Hong - - 2005
Two lines of Large White pigs of common genetic origin were divergently selected over four years for high and low growth rate during a 6 week post-weaning test period in which all pigs were fed the same total amount of food (80% of estimated ad libitum intake). Genetic parameters and ...
Abramsson-Zetterberg Lilianne - - 2005
Semicarbazide, mainly produced for research purposes, has been known for various reasons within foods. It occurs as one of the break-down products of nitrofurans, a group of widely used veterinary drugs, and as a break-down product of azodicarbonamide used as a flour treatment agent to improve baking properties. Furthermore, it ...
Tucker Michelle Z - - 2005
To determine the effects of brief food restriction on fatty acid (FA) metabolism in old muscle, hind limbs of 24-month F344/BN rats fed either ad libitum (AL) or 60% food restricted (FR) for 28 days were perfused under hyperglycemic-hyperinsulinemic conditions. Basal glucose and insulin levels were significantly lower (p<.05) in ...
Carey James R - - 2005
Lifespan in individually housed medflies (virgins of both sexes) and daily reproduction for females were studied following one of 12 dietary restriction (DR) treatments in which the availability of high-quality food (yeast-sugar mixture) for each fly was based on a Markov chain feeding scheme--a stochastic dietary regime which specifies that ...
Boulamery-Velly A - - 2005
The effects of food on biological rhythms may influence the findings of chronopharmacological studies. The present study evaluated the influence of a restricted food access during the rest (light) span of nocturnally active Wistar rats on the 24 h time organization of biological functions in terms of the circadian rhythms ...
Séguy M - - 2005
Microcebus murinus, a small nocturnal Malagasy primate, exhibits adaptive energy-saving strategies such as daily hypothermia and gregarious patterns during diurnal rest. To determine whether ambient temperature (T(a)), food restriction and nest sharing can modify the daily body temperature (T(b)) rhythm, T(b) was recorded by telemetry during winter in six males ...
de Groot Marleen H M - - 2004
If food is presented for a limited duration once every 24 h, rats will gradually develop increased activity in the hours preceding mealtime, even if this is during a time of day when they are normally inactive. This food-anticipatory activity (FAA) is mediated by the entrainment of an endogenous self-sustaining ...
Pan Yan - - 2004
Chronic food restriction augments the rewarding effect of centrally administered psychostimulant drugs and this effect may involve a previously documented upregulation of D-1 dopamine receptor-mediated MAP kinase signaling in nucleus accumbens (NAc) and caudate-putamen (CPu). Psychostimulants are known to induce striatal glutamate release, and group I metabotropic glutamate receptors (mGluR) ...
Mew John R C - - 2004
Over the last 100 years, many theories have attempted to explain the cause of malocclusion. Most have stated that it is inherited, but, more recently, greater emphasis has been placed on the influence of the environment, especially the activity and the posture of the oral soft tissues. Unfortunately, it is ...
Asadi-Pooya Ali Akbar - - 2004
PURPOSE: Almost 1000 years ago, Avicenna, the great Iranian scientist, recommended that patients with epilepsy should avoid some foods. In the present study we attempted to identify beliefs and experiences of families with epileptic children with respect to the need for specific dietary restrictions in these patients. METHODS: A cross-sectional ...
Mieda Michihiro - - 2004
Temporal restriction of feeding can entrain circadian behavioral and physiological rhythms in mammals. Considering the critical functions of the hypothalamic orexin (hypocretin) neuropeptides in promoting wakefulness and locomotor activity, we examined the role of orexin neurons in the adaptation to restricted feeding. In orexin neuron-ablated transgenic mice, the food-entrained rhythmicity ...
1 2 3 4 5 6 7 8 9 10 >