Tumor cryoablation is a clinical procedure where supercooled probes are used to destroy cancerous lesions. Cryoablation is a safe and effective palliative treatment for skeletal metastases, providing immediate and long term pain relief, increasing mobility and improving quality of life. Ideally, lesions are encompassed by an ice ball and frozen to a sufficiently low temperature to ensure cell d...

This paper addresses the ways in which heat loss effector functions change with maturation and aging, using data obtained in our laboratory. Prepubertal children have an underdeveloped sweat function compared with young adults; this is compensated by a greater surface area-to-mass ratio and relatively greater heat loss from cutaneous vasodilation on the head and trunk when the air temperature i...

Our ability to accurately forecast species' geographical responses to climate change requires knowledge of the proximate and ultimate drivers of their distribution. Here, we consider the ecophysiological and demographic determinants of the distribution of a partial migrant, the North American field sparrow, Spizella pusilla. From 1940 to 1963, the field sparrow extended its winter northern rang...

The purpose of this project was to test the hypothesis that increases in muscle sympathetic nerve activity (MSNA) during an orthostatic challenge is attenuated in heat-stressed individuals. To accomplish this objective, MSNA was measured during graded lower body negative pressure (LBNP) in nine subjects under normothermic and heat-stressed conditions. Progressive LBNP was applied at -3, -6, -9,...

PURPOSE We performed two experiments to determine whether cutaneous microvascular adaptations in response to repeated core temperature (Tc) elevation are mediated by increases in skin blood flow (SkBF) and/or skin temperature. METHODS Healthy subjects participated for 8 wk in thrice-weekly bouts of 30-min lower limb heating (40°C). In study 1, both forearms were "clamped" at basal skin temper...

BACKGROUND AND OBJECTIVES Epidural anesthesia decreases the core temperatures triggering vasoconstriction and shivering, presumably by increasing apparent (as opposed to actual) lower-body temperature. We therefore tested the hypothesis that epidural anesthesia also increases the overall perception of warmth. METHODS We studied 8 volunteers in a randomized, cross-over protocol separated by at...

The aim of this study was to describe the epidemiological profile of snakebite accidents in the healthcare macroregion of the north of the State of Minas Gerais, Brazil. Database information on snakebite accidents covering the period from January 2002 to December 2006 was analyzed. It was found that 10,553 cases were notified, and that the samples were noticeably larger in the months of hot and...

Passive heat stress increases core and skin temperatures and reduces tolerance to simulated hemorrhage (lower body negative pressure; LBNP). We tested whether exercise-induced heat stress reduces LBNP tolerance to a greater extent relative to passive heat stress, when skin and core temperatures are similar. Eight participants (6 males, 32 ± 7 yr, 176 ± 8 cm, 77.0 ± 9.8 kg) underwent LBNP to pre...

Chronic stress is associated with increased risk of cardiovascular diseases. Aging is also associated with vascular dysfunction. We hypothesize that chronic stress accelerates collateral dysfunction in old mice. Mice were subjected to either chronic social defeat (CSD) or chronic cold stress (CCS). The CSD mice were housed in a box inside an aggressor's cage and exposed to the aggressor. The CC...

We have found that temperature can have a striking effect upon protein export in Escherichia coli, suggesting that there is a cold-sensitive step in the protein export pathway. Cs mutations comprise the largest class of mutations affecting the membrane-localized Sec proteins SecD, SecE, SecF and SecY. Although some of these mutations could encode cold-labile proteins, this is unlikely to accoun...