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Cellular and Molecular Life Sciences :... Sep 2011Many of the live human and animal vaccines that are currently in use are attenuated by virtue of their temperature-sensitive (TS) replication. These vaccines are able to... (Review)
Review
Many of the live human and animal vaccines that are currently in use are attenuated by virtue of their temperature-sensitive (TS) replication. These vaccines are able to function because they can take advantage of sites in mammalian bodies that are cooler than the core temperature, where TS vaccines fail to replicate. In this article, we discuss the distribution of temperature in the human body, and relate how the temperature differential can be exploited for designing and using TS vaccines. We also examine how one of the coolest organs of the body, the skin, contains antigen-processing cells that can be targeted to provoke the desired immune response from a TS vaccine. We describe traditional approaches to making TS vaccines, and highlight new information and technologies that are being used to create a new generation of engineered TS vaccines. We pay particular attention to the recently described technology of substituting essential genes from Arctic bacteria for their homologues in mammalian pathogens as a way of creating TS vaccines.
Topics: Antigen-Presenting Cells; Bacterial Vaccines; Body Temperature; Genetic Engineering; Humans; Models, Molecular; Skin
PubMed: 21626408
DOI: 10.1007/s00018-011-0734-2 -
International Journal of Biometeorology Jun 2023Healthy adult horses can balance accumulation and dissipation of body heat to maintain their body temperature between 37.5 and 38.5 °C, when they are in their... (Review)
Review
Healthy adult horses can balance accumulation and dissipation of body heat to maintain their body temperature between 37.5 and 38.5 °C, when they are in their thermoneutral zone (5 to 25 °C). However, under some circumstances, such as following strenuous exercise under hot, or hot and humid conditions, the accumulation of body heat exceeds dissipation and horses can suffer from heat stress. Prolonged or severe heat stress can lead to anhidrosis, heat stroke, or brain damage in the horse. To ameliorate the negative effects of high heat load in the body, early detection of heat stress and immediate human intervention is required to reduce the horse's elevated body temperature in a timely manner. Body temperature measurement and deviations from the normal range are used to detect heat stress. Rectal temperature is the most commonly used method to monitor body temperature in horses, but other body temperature monitoring technologies, percutaneous thermal sensing microchips or infrared thermometry, are currently being studied for routine monitoring of the body temperature of horses as a more practical alternative. When heat stress is detected, horses can be cooled down by cool water application, air movement over the horse (e.g., fans), or a combination of these. The early detection of heat stress and the use of the most effective cooling methods is important to improve the welfare of heat stressed horses.
Topics: Humans; Horses; Animals; Humidity; Respiration; Hot Temperature; Body Temperature; Fever; Body Temperature Regulation
PubMed: 37060454
DOI: 10.1007/s00484-023-02467-7 -
Archives of Disease in Childhood Apr 2006Body temperature is commonly measured to confirm the presence or absence of fever. However, there remains considerable controversy regarding the most appropriate... (Review)
Review
Body temperature is commonly measured to confirm the presence or absence of fever. However, there remains considerable controversy regarding the most appropriate thermometer and the best anatomical site for temperature measurement. Core temperature is generally defined as the temperature measured within the pulmonary artery. Other standard core temperature monitoring sites (distal oesophagus, bladder, and nasopharynx) are accurate to within 0.1-0.2 degrees C of core temperature and are useful surrogates for deep body temperature. However, as deep-tissue measurement sites are clinically inaccessible, physicians have utilised other sites to monitor body temperature including the axilla, skin, under the tongue, rectum, and tympanic membrane. Recent studies have shown that tympanic temperature accurately reflects pulmonary artery temperature, even when body temperature is changing rapidly. Once outstanding issues are addressed, the tympanic site is likely to become the gold standard for measuring temperature in children.
Topics: Axilla; Body Temperature; Child; Evidence-Based Medicine; Fever; Humans; Rectum; Skin Temperature; Thermometers
PubMed: 16551792
DOI: 10.1136/adc.2005.088831 -
Acta Physiologica (Oxford, England) Mar 2014This review analyses whether skin temperature represents ambient temperature and serves as a feedforward signal for the thermoregulation system, or whether it is one of... (Review)
Review
This review analyses whether skin temperature represents ambient temperature and serves as a feedforward signal for the thermoregulation system, or whether it is one of the body's temperatures and provides feedback. The body is covered mostly by hairy (non-glabrous) skin, which is typically insulated from the environment (with clothes in humans and with fur in non-human mammals). Thermal signals from hairy skin represent a temperature of the insulated superficial layer of the body and provide feedback to the thermoregulation system. It is explained that this feedback is auxiliary, both negative and positive, and that it reduces the system's response time and load error. Non-hairy (glabrous) skin covers specialized heat-exchange organs (e.g. the hand), which are also used to explore the environment. In thermoregulation, these organs are primarily effectors. Their main thermosensory-related role is to assess local temperatures of objects explored; these local temperatures are feedforward signals for various behaviours. Non-hairy skin also contributes to the feedback for thermoregulation, but this contribution is limited. Autonomic (physiological) thermoregulation does not use feedforward signals. Thermoregulatory behaviours use both feedback and feedforward signals. Implications of these principles to thermopharmacology, a new approach to achieving biological effects by blocking temperature signals with drugs, are discussed.
Topics: Animals; Body Temperature Regulation; Humans; Skin Temperature
PubMed: 24716231
DOI: 10.1111/apha.12231 -
American Journal of Physiology. Renal... Dec 2013Hibernators periodically undergo profound physiological changes including dramatic reductions in metabolic, heart, and respiratory rates and core body temperature. This... (Review)
Review
Hibernators periodically undergo profound physiological changes including dramatic reductions in metabolic, heart, and respiratory rates and core body temperature. This review discusses the effect of hypoperfusion and hypothermia observed during hibernation on glomerular filtration and renal plasma flow, as well as specific adaptations in renal architecture, vasculature, the renin-angiotensin system, and upregulation of possible protective mechanisms during the extreme conditions endured by hibernating mammals. Understanding the mechanisms of protection against organ injury during hibernation may provide insights into potential therapies for organ injury during cold storage and reimplantation during transplantation.
Topics: Adaptation, Physiological; Animals; Body Temperature; Hibernation; Humans; Kidney; Renin-Angiotensin System
PubMed: 24049148
DOI: 10.1152/ajprenal.00675.2012 -
Scientific Reports Apr 2023Mammalian and avian torpor is highly effective in reducing energy expenditure. However, the extent of energy savings achieved and thus long-term survival appear to...
Mammalian and avian torpor is highly effective in reducing energy expenditure. However, the extent of energy savings achieved and thus long-term survival appear to differ between species capable of multiday hibernation and species restricted to daily heterothermy, which could, however, be due to thermal effects. We tested how long-term survival on stored body fat (i.e. time to lean body mass), crucial for overcoming adverse periods, is related to the pattern of torpor expressed under different ambient temperatures (T: 7 °C typical of hibernation, 15 and 22 °C typical of daily torpor) in the small marsupial hibernator the pygmy-possum (Cercartetus nanus). Possums expressed torpor at all Ts and survived without food for 310 days on average at T 7 °C, 195 days at T 15 °C, and 127 days at T 22 °C. At T 7 and 15 °C, torpor bout duration (TBD) increased from < 1-3 to ~ 5-16 days over 2 months, whereas at T 22 °C, TBD remained at < 1 to ~ 2 days. At all Ts daily energy use was substantially lower and TBD and survival times of possums much longer (3-12 months) than in daily heterotherms (~ 10 days). Such pronounced differences in torpor patterns and survival times even under similar thermal conditions provide strong support for the concept that torpor in hibernators and daily heterotherms are physiologically distinct and have evolved for different ecological purposes.
Topics: Animals; Temperature; Body Temperature; Torpor; Hibernation; Marsupialia; Mammals; Energy Metabolism
PubMed: 37095170
DOI: 10.1038/s41598-023-33646-6 -
Physiology (Bethesda, Md.) May 2018Mammals are characterized by a stable core body temperature. When maintenance of core temperature is challenged by ambient or internal heat loads, mammals increase blood... (Review)
Review
Mammals are characterized by a stable core body temperature. When maintenance of core temperature is challenged by ambient or internal heat loads, mammals increase blood flow to the skin, sweat and/or pant, or salivate. These thermoregulatory responses enable evaporative cooling at moist surfaces to dissipate body heat. If water losses incurred during evaporative cooling are not replaced, body fluid homeostasis is challenged. This article reviews the way mammals balance thermoregulation and osmoregulation.
Topics: Animals; Body Temperature; Body Temperature Regulation; Homeostasis; Humans; Osmoregulation; Water-Electrolyte Balance
PubMed: 29616878
DOI: 10.1152/physiol.00037.2017 -
Frontiers in Bioscience (Landmark... Jan 2010This article reviews the literature on the circadian rhythm of body temperature. It starts with a description of the typical pattern of oscillation under standard... (Review)
Review
This article reviews the literature on the circadian rhythm of body temperature. It starts with a description of the typical pattern of oscillation under standard laboratory conditions, with consideration being given to intra- and interspecies differences. It then addresses the influence of environmental factors (principally ambient temperature and food availability) and biological factors (including locomotor activity, maturation and aging, body size, and reproductive state). A discussion of the interplay of rhythmicity and homeostasis (including both regulatory and heat-exchange processes) is followed by concluding remarks.
Topics: Aging; Animals; Body Temperature; Body Temperature Regulation; Body Weight; Circadian Rhythm; Energy Metabolism; Humans; Species Specificity; Temperature
PubMed: 20036834
DOI: 10.2741/3634 -
Arquivos Brasileiros de Cardiologia Jun 2019
Topics: Animals; Body Temperature; Body Temperature Regulation; Physical Conditioning, Animal; Physical Exertion; Rats
PubMed: 31188960
DOI: 10.5935/abc.20190081 -
The Journal of Neuroscience Nursing :... Apr 2018Shivering is common during targeted temperature management, and control of shivering can be challenging if clinicians are not familiar with the available options and... (Review)
Review
BACKGROUND
Shivering is common during targeted temperature management, and control of shivering can be challenging if clinicians are not familiar with the available options and recommended approaches.
PURPOSE
The purpose of this review was to summarize the most relevant literature regarding various treatments available for control of shivering and suggest a recommended approach based on latest data.
METHODS
The electronic databases PubMed/MEDLINE and Google Scholar were used to identify studies for the literature review using the following keywords alone or in combination: "shivering treatment," "therapeutic hypothermia," "core temperature modulation devices," and "targeted temperature management."
RESULTS
Nonpharmacologic methods were found to have a very low adverse effect profile and ease of use but some limitations in complete control of shivering. Pharmacologic methods can effectively control shivering, but some have adverse effects, such that risks and benefits to the patient have to be balanced.
CONCLUSION
An approach is provided which suggests that treatment for shivering control in targeted temperature management should be initiated before the onset of therapeutic hypothermia or prior to any attempt at lowering patient core temperature, with medications including acetaminophen, buspirone, and magnesium sulfate, ideally with the addition of skin counterwarming. After that, shivering intervention should be determined with the help of a shivering scale, and stepwise escalation can be implemented that balances shivering treatment with sedation, aiming to provide the most shivering reduction with the least sedating medications and reserving paralytics for the last line of treatment.
Topics: Body Temperature; Buspirone; Humans; Hypothermia, Induced; Serotonin Receptor Agonists; Shivering
PubMed: 29278601
DOI: 10.1097/JNN.0000000000000340