Physiology & behavior
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Physiology & behavior · Aug 2016
Review Historical Article2015 Distinguished career award: Reflections on a career in science.
I was very pleased to receive the 2015 Distinguished Career Award from SSIB. This brief manuscript contains reminisces that might stir up pleasant memories in the older members of SSIB and also some general thoughts that I hope will be of value to the younger investigators who are closer to the beginning of their scientific careers. ⋯ They include Neal Miller, my doctoral mentor at Yale; Joe Holmes and Alan Epstein, my postdoctoral mentors; George Wolf and Reed Hainsworth, graduate student colleagues; John Brobeck, Paul Rozin, and Phil Teitelbaum, Michael Zigmond, Joe Verbalis, Jim Smith, and Alan Sved, faculty colleagues; Derek Denton, Paul McHugh, and James Fitzsimons, scientific role models; John Bruno, Steve Fluharty, and Linda Rinaman, post-doctoral trainees at Pitt; and Lori Flanagan, Kath Curtis, Michael Bushey, Mike Bykowski, Reza Manesh, Carrie Smith, Jennifer Vaughan, and Myriam Stricker, student trainees at Pitt. I thank them all and also my colleagues in SSIB not only for the honor of this award but for providing an abundant supply of insights and discoveries that have stimulated me throughout my adult life, in addition to being an attentive community in supporting my own work.
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Physiology & behavior · Sep 2013
ReviewBrown adipose tissue thermogenesis, the basic rest-activity cycle, meal initiation, and bodily homeostasis in rats.
Laboratory rats alternate between behaviorally active and inactive states every 1-2h throughout the 24hour day, the ultradian basic rest-activity cycle (BRAC). During the behaviorally active phases of the BRAC, brown adipose tissue (BAT) temperature, body and brain temperature, and arterial pressure and heart rate increase in an integrated manner. Since the BAT temperature increases are substantially greater than the corresponding body and brain temperature increases, BAT thermogenesis contributes to the body and brain temperature increases. ⋯ Rather than being triggered by changes in levels of body fuels or other meal-associated factors, in sedentary laboratory rats with ad libitum access to food, meal initiation normally occurs as part of the centrally-programmed ultradian BRAC. BRAC-associated BAT temperature increases occur in a thermoneutral environment and they are not preceded by falls in body or brain temperature, so they are not homeostatic thermoregulatory responses. The pattern of integrated behaviors and physiological functions associated with the BRAC presumably reflects Darwinian natural selection, and homeostatic thermoregulatory explanations of the BRAC-associated changes in temperature should be considered in this context.
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Physiology & behavior · Apr 2012
ReviewMediators of allostasis and systemic toxicity in bipolar disorder.
Bipolar disorder is associated with a high rate of medical and psychiatric comorbidities. This burden of illness, along with cognitive impairment, is seen particularly in late cases, after multiple episodes. These changes in clinical presentation that take place over time have been recently conceptualized as "neuroprogression". ⋯ Allostatic load is engendered by several factors which interact in a nonlinear manner. Glucocorticoids are fundamental mediators; when chronically in excess, glucocorticoids initiate a series of bodily dysfunctions that may include cortisol-related mitochondrial dysfunction, oxidative stress, inflammation and decrease in the expression of neuroprotective factors. In the present review we examine the role of allostatic load in the illness progression that takes place in bipolar disorder.
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Physiology & behavior · Aug 2008
ReviewRelationships between human thirst, hunger, drinking, and feeding.
There is a widely held view that hunger prompts feeding to ensure energy needs are met, while thirst cues drinking to address hydration requirements. However, recent changes in the nature of the food supply and eating patterns have raised questions about the functionality of these relationships with respect to maintaining energy balance. The increasing consumption of energy-yielding beverages and foods with diluted energy density, through the use of ingredients such as high-intensity sweeteners and fat replacers, poses new challenges to presumed homeostatic energy regulatory mechanisms. ⋯ Our data indicates that, due to a number of plausible factors, neither absolute values nor changes of hunger or thirst are strong predictors of energy intake. However, it is proposed that stable, high thirst facilitates drinking, and with the increased availability and use of energy-yielding beverages that have low satiety properties, can promote positive energy balance. There are marked individual differences in mean daily hunger and thirst ratings with unknown implications for energy balance.
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Physiology & behavior · Sep 2007
ReviewPrevention of Alzheimer's disease and dementia. Major findings from the Kungsholmen Project.
The aging of the population is a worldwide phenomenon, and studying age-related diseases has become a relevant issue from both a scientific and a public health perspective. This review summarises the major findings concerning prevention of Alzheimer's disease (AD) and other dementias from a population-based study, the Kungsholmen Project. ⋯ Although many aspects of the dementias are still unclear, some risk factors have been identified and interesting hypotheses have been suggested for other putative risk or protective factors. At the moment it is also possible to delineate some preventative strategies for dementia.