PubMed · 5059613
The source did not provide an abstract. Follow the original record for more information.
Explore connections, maps & timelines
D S Sumner, D E Strandness. 1972. An abnormal finger pulse associated with cold sensitivity.. https://doi.org/10.1097/00000658-197202000-00024
Cite the original work for its findings. Save a collection to share your selection of sources.
KEEP EXPLORING
Cytokines are highly inducible, secreted proteins mediating intercellular communication in the nervous and immune system. Fever is the multiphasic response of elevation and decline of the body core temperature regulated by central thermoregulatory mechanisms localized in the preoptic area of the hypothalamus. The discovery that several proinflammatory cytokines act as endogenous pyrogens and that other cytokines can act as antipyretic agents provided a link between the immune and the central nervous systems and stimulated the study of the central actions of cytokines. The proinflammatory cytokines interleukin 1 (IL-1), interleukin 6 (IL-6) and the tumor necrosis factor alpha (TNF) as well as the antiinflammatory cytokines interleukin 1 receptor antagonist (IL-1ra) and interleukin 10 (IL-10) have been most investigated for their pyrogenic or antipyretic action. The experimental evidence demonstrating the role of these secreted proteins in modulating the fever response is as follows: 1) association between cytokine levels in serum and CSF and fever; 2) finding of the presence of cytokine receptors on various cell types in the brain and demonstration of the effects of pharmacological application of cytokines and of their neutralizing antibodies on the fever response; 3) fever studies on cytokine- and cytokine receptor- transgenic models. Studies on the peripheral and the central action of cytokines demonstrated that peripheral cytokines can communicate with the brain in several ways including stimulation of afferent neuronal pathways and induction of the synthesis of a non cytokine pyrogen, i.e. PGE2, in endothelial cells in the periphery and in the brain. Cytokines synthesized in the periphery may act by crossing the blood brain barrier and acting directly via neuronal cytokine receptors. The mechanisms that ultimately mediate the central action of cytokines and of LPS on the temperature-sensitive neurons in the preoptic hypothalamic region involved in thermoregulation, directly or via second mediators, remain to be fully elucidated.
The amounts of water, carbohydrate and salt that athletes are advised to ingest during exercise are based upon their effectiveness in attenuating both fatigue as well as illness due to hyperthermia, dehydration or hyperhydration. When possible, fluid should be ingested at rates that most closely match sweating rate. When that is not possible or practical or sufficiently ergogenic, some athletes might tolerate body water losses amounting to 2% of body weight without significant risk to physical well-being or performance when the environment is cold (e.g. 5-10 degrees C) or temperate (e.g. 21-22 degrees C). However, when exercising in a hot environment ( > 30 degrees C), dehydration by 2% of body weight impairs absolute power production and predisposes individuals to heat injury. Fluid should not be ingested at rates in excess of sweating rate and thus body water and weight should not increase during exercise. Fatigue can be reduced by adding carbohydrate to the fluids consumed so that 30-60 g of rapidly absorbed carbohydrate are ingested throughout each hour of an athletic event. Furthermore, sodium should be included in fluids consumed during exercise lasting longer than 2 h or by individuals during any event that stimulates heavy sodium loss (more than 3-4 g of sodium). Athletes do not benefit by ingesting glycerol, amino acids or alleged precursors of neurotransmitter. Ingestion of other substances during exercise, with the possible exception of caffeine, is discouraged. Athletes will benefit the most by tailoring their individual needs for water, carbohydrate and salt to the specific challenges of their sport, especially considering the environment's impact on sweating and heat stress.
Explore the source record for details and available documents.