Extracellular and intracellular carbon dioxide concentration as a function of temperature in the toad Bufo marinus.

1994 ◽  
Vol 195 (1) ◽  
pp. 345-360 ◽  
Author(s):  
J N Stinner ◽  
D L Newlon ◽  
N Heisler

Previous studies of reptiles and amphibians have shown that changing the body temperature consistently produces transient changes in the respiratory exchange ratio (RE) and, hence, changes in whole-body CO2 stores, and that the extracellular fluid compartment contributes to the temperature-related changes in CO2 stores. The purpose of this study was to determine whether the intracellular fluid compartment contributes to the changes in CO2 stores in undisturbed resting cane toads. Increasing body temperature from 10 to 30 degrees C temporarily elevated RE, and returning body temperature to 10 degrees C temporarily lowered RE. The estimated average change in whole-body CO2 stores associated with the transient changes in RE was 1.0 +/- 0.8 mmol kg-1 (+/- S.D., N = 6). Plasma [CO2] and, thus, extracellular fluid [CO2], were unaffected by the temperature change. Plasma calcium levels were also unaffected, so that bone CO2 stores did not contribute to changes in whole-body CO2 stores. Intracellular [CO2] was determined for the lung, oesophagus, stomach, small intestine, liver, ventricle, red blood cells, skin and 14 skeletal muscles. [CO2] was significantly lower (P < 0.05) at higher temperature in 10 of these, and seven others, although not statistically significant (P > 0.05), had mean values at least 0.5 mmol kg-1 lower at the higher temperature. The average change in intracellular [CO2] for all tissues examined was -0.165 mmol kg-1 degrees C-1. We conclude that, in cane toads, the temperature-related transients in RE result from intracellular CO2 adjustments, that different tissues have unique intracellular CO2/temperature relationships, and that a combination of respiratory and ion-exchange mechanisms is used to adjust pH as temperature changes.

Author(s):  
Joanna M. Bukowska ◽  
Małgorzata Jekiełek ◽  
Dariusz Kruczkowski ◽  
Tadeusz Ambroży ◽  
Jarosław Jaszczur-Nowicki

Background: The aim of the study is to assess the body balance and podological parameters and body composition of young footballers in the context of the control of football training. Methods: The study examined the distribution of the pressure of the part of the foot on the ground, the arch of the foot, and the analysis of the body composition of the boys. The pressure center for both feet and the whole body was also examined. The study involved 90 youth footballers from Olsztyn and Barczewo in three age groups: 8–10 years, 11–13 years old, and 14–16 years. The study used the Inbody 270 body composition analyzer and the EPSR1, a mat that measures the pressure distribution of the feet on the ground. Results: The results showed statistically significant differences in almost every case for each area of the foot between the groups of the examined boys. The most significant differences were observed for the metatarsal area and the left heel. In the case of stabilization of the whole body, statistically significant differences were noted between all study groups. In the case of the body composition parameters, in the examined boys, a coherent direction of changes was noticed for most of them. The relationships and correlations between the examined parameters were also investigated. The significance level in the study was set at p < 0.05. Conclusions: Under the training rigor, a statistically significant increase in stability was observed with age. The total length of the longitudinal arch of both feet of the examined boys showed a tendency to flatten in direct proportion to the age of the examined boys. Mean values of the body composition parameters reflect changes with the ontogenetic development, basic somatic parameters (body height and weight) and training experience, and thus with the intensity and volume of training. This indicates a correct training process that does not interfere with the proper development of the body in terms of tissue and biochemical composition.


1961 ◽  
Vol 38 (2) ◽  
pp. 301-314 ◽  
Author(s):  
BODIL NIELSEN

1. In two species of Lacerta (L. viridis and L. sicula) the effects on respiration of body temperature (changes in metabolic rate) and of CO2 added to the inspired air were studied. 2. Pulmonary ventilation increases when body temperature increases. The increase is brought about by an increase in respiratory frequency. No relationship is found between respiratory depth and temperature. 3. The rise in ventilation is provoked by the needs of metabolism and is not established for temperature regulating purposes (in the temperature interval 10°-35°C). 4. The ventilation per litre O2 consumed has a high numerical value (about 75, compared to about 20 in man). It varies with the body temperature and demonstrates that the inspired air is better utilized at the higher temperatures. 5. Pulmonary ventilation increases with increasing CO2 percentages in the inspired air between o and 3%. At further increases in the CO2 percentage (3-13.5%) it decreases again. 6. At each CO2 percentage the pulmonary ventilation reaches a steady state after some time (10-60 min.) and is then unchanged over prolonged periods (1 hr.). 7. The respiratory frequency in the steady state decreases with increasing CO2 percentages. The respiratory depth in the steady state increases with increasing CO2 percentages. This effect of CO2 breathing is not influenced by a change in body temperature from 20° to 30°C. 8. Respiration is periodically inhibited by CO2 percentages above 4%. This inhibition, causing a Cheyne-Stokes-like respiration, ceases after a certain time, proportional to the CO2 percentage (1 hr. at 8-13% CO2), and respiration becomes regular (steady state). Shift to room air breathing causes an instantaneous increase in frequency to well above the normal value followed by a gradual decrease to normal values. 9. The nature of the CO2 effect on respiratory frequency and respiratory depth is discussed, considering both chemoreceptor and humoral mechanisms.


PEDIATRICS ◽  
1963 ◽  
Vol 32 (4) ◽  
pp. 691-702
Author(s):  
Sid Robinson

The central body temperature of a man rises gradually during the first half hour of a period of work to a higher level and this level is precisely maintained until the work is stopped; body temperature then slowly declines to the usual resting level. During prolonged work the temperature regulatory center in the hypothalamus appears to be reset at a level which is proportional to the intensity of the work and this setting is independent of environmental temperature changes ranging from cold to moderately warm. In hot environments the resistance to heat loss may be so great that all of the increased metabolic heat of work cannot be dissipated and the man's central temperature will rise above the thermostatic setting. If this condition of imbalance is continued long enough heat stroke will ensue. We have found that in a 3 mile race lasting only 14 minutes on a hot summer day a runner's rectal temperature may rise to 41.1°C., with heat stroke imminent. The physiological regulation of body temperature of men in warm environments and during the increased metabolic heat production of work is dependent on sweating to provide evaporative cooling of the skin, and on adjustments of cutaneous blood flow which determine the conductance of heat from the deeper tissues to the skin. The mechanisms of regulating these responses during work are complex and not entirely understood. Recent experiments carried out in this laboratory indicate that during work, sweating may be regulated by reflexes originating from thermal receptors in the veins draining warm blood from the muscles, summated with reflexes from the cutaneous thermal receptors, both acting through the hypothalamic center, the activity of which is increased in proportion to its own temperature. At the beginning of work the demand for blood flow to the muscles results in reflex vasoconstriction in the skin. As the body temperature rises the thermal demand predominates and the cutaneous vessels dilate, increasing heat conductance to the skin. Large increments in cardiac output and compensatory vasoconstriction in the abdominal viscera make these vascular adjustments in work possible without circulatory embarrassment.


2019 ◽  
Vol 2 (2) ◽  
pp. 113-122
Author(s):  
Padila Padila ◽  
Ida Agustien

This study aims to compare the average change in body temperature in a single wall incubator with a single wall incubator with hood in preterm infants with hypothermia. The design of this study uses a comparative descriptive method. The results of the study in the group of preterm infants with hypothermia in a single wall incubator with a lid significantly increased mean body temperature changes with a mean value of 36.09 variance 0.152 while for preterm infants with hypothermia in a single wall incubator a mean value of 35.35 variance values 0.859 and obtained t count from the two study groups namely 2.551 and 1.717 t table. In conclusion, a single wall incubator with a lid increases body temperature in premature infants with hypothermia compared to a single wall incubator.   Keywords: Hypothermia, Incubator, Premature


1985 ◽  
Vol 249 (2) ◽  
pp. E227-E233 ◽  
Author(s):  
A. H. Beddoe ◽  
S. J. Streat ◽  
G. L. Hill

It is widely believed that increased hydration of the fat-free body accompanies most major disease processes as a result of contraction of the body cell mass and expansion of the extracellular fluid. Measurements of total body water (TBW) and total body nitrogen in 68 normal volunteers and 95 surgical ward patients presenting for intravenous nutrition have been used to derive ratios of TBW to fat-free mass (TBW:FFM) and protein indices (PI), where PI is defined as the ratio of measured total body protein to predicted TBP. Mean values of PI were 1.009 +/- 0.116 (SD) and 0.783 +/- 0.152 in the normal and patient groups, respectively, corresponding to mean TBW:FFM ratios of 0.719 +/- 0.016 and 0.741 +/- 0.029. However, 48 patients had normal TBW:FFM despite having lost 15% of body protein. A theoretical model of body composition changes in catabolic illness is presented, which is in accord with the patient data, demonstrating that TBW:FFM does not necessarily increase in catabolic illness and that the ratio masks underlying shifts in body fluid compartments.


1961 ◽  
Vol 16 (3) ◽  
pp. 538-540
Author(s):  
Paul W. Willard ◽  
Steven M. Horvath

Blood volumes with simultaneous blood- and red cell-distribution measurements were determined by the Cr51 technique in four groups of rats. In splenectomized and nonsplenectomized animals, blood volume of the whole body, lung, spleen, liver, kidney, heart, diaphragm, and gastrocnemius muscle was measured in both the control rats (body temperature 37 C) and in rats with hypothermically induced cardiac arrest (body temperature 8–9 C). Splenectomy caused alterations in some visceral blood volumes without concurrent changes in red cell mass. With cardiac arrest increased quantities of blood and red cell mass were observed in the lung, liver, and gastrocnemius in both splenectomized and nonsplenectomized groups. In the nonsplenectomized animals an increase of over 100 % in spleen blood volume was observed. When the two hypothermic groups were compared, differences existed only in blood volume of the lung, heart, and kidney. Hypothermia induced a pattern of blood redistribution toward visceral areas of the body. Submitted on October 14, 1960


The object of this enquiry is to find out how much heat can be gained, or cold lost from the body, by the local cooling or warming of a small part, by cooling the hands in a stream of cold water, warming the feet in a hot foot­ bath, or by a foot-warmer. In order to secure the beneficial effect of open windows, the breathing of cool air of low-vapour tension, and stimulation of body metabolism by such air ventilating the clothed and naked parts of the skin, the general heating of rooms by hot-water coils might be replaced by small heaters kept a few degrees above body temperature and locally applied to each individual, and each under the individual’s control. Electric heaters have been used by aeroplanists placed beneath their outer garments. One of us(l) recently published results showing that heating or cooling the hands can effectively heat or cool the whole body. We record further experiments of a like nature.


2020 ◽  
Vol 15 (1) ◽  
Author(s):  
Yi Su ◽  
Chunsheng Ma ◽  
Jing Chen ◽  
Huiping Wu ◽  
Weixiang Luo ◽  
...  

Abstract In recent years, the development and research of flexible sensors have gradually deepened, and the performance of wearable, flexible devices for monitoring body temperature has also improved. For the human body, body temperature changes reflect much information about human health, and abnormal body temperature changes usually indicate poor health. Although body temperature is independent of the environment, the body surface temperature is easily affected by the surrounding environment, bringing challenges to body temperature monitoring equipment. To achieve real-time and sensitive detection of various parts temperature of the human body, researchers have developed many different types of high-sensitivity flexible temperature sensors, perfecting the function of electronic skin, and also proposed many practical applications. This article reviews the current research status of highly sensitive patterned flexible temperature sensors used to monitor body temperature changes. First, commonly used substrates and active materials for flexible temperature sensors have been summarized. Second, patterned fabricating methods and processes of flexible temperature sensors are introduced. Then, flexible temperature sensing performance are comprehensively discussed, including temperature measurement range, sensitivity, response time, temperature resolution. Finally, the application of flexible temperature sensors based on highly delicate patterning are demonstrated, and the future challenges of flexible temperature sensors have prospected.


1993 ◽  
Vol 265 (3) ◽  
pp. E513-E520
Author(s):  
R. E. Ostlund

Important work by others has shown that human whole body cholesterol metabolism can be described by a three-compartment model computed from plasma cholesterol specific activity after an intravenous infusion of labeled cholesterol. However, some parameters of that model cannot be estimated precisely [coefficient of variation (CV) 15-19% after 40 wk of follow-up], making its use in routine clinical investigation difficult. On the other hand, a simpler two-compartment model can be calculated with excellent precision from only 10 wk of data (CV 2-8%), but its parameters are inaccurate (for example, the size of the central pool is overestimated by 20%, and the rate constant for fractional excretion of cholesterol from the body is underestimated by 15%). Thus both three-compartment and two-compartment models of cholesterol turnover have important limitations. An alternative is provided by a minimal model that takes advantage of the increased precision expected in the solution of models with fewer parameters. A three-compartment structure is used, but only four (rather than 6 or more) parameters are calculated: the mass of the rapidly mixing central cholesterol compartment, the fractional rate of cholesterol elimination from the body, and the average forward and reverse rate constants for cholesterol transfer between the rapid compartment and both slower compartments. Each of these parameters can be determined unambiguously (without the need to use a minimum or maximum estimate), accurately (mean values within 2% of theory), and with precision (CV 3-13%).(ABSTRACT TRUNCATED AT 250 WORDS)


2017 ◽  
Vol 2017 ◽  
pp. 1-10 ◽  
Author(s):  
Jia-Min Yang ◽  
Gang Li ◽  
Min Wang ◽  
Yi-Xi Jin ◽  
Feng-Jie Zheng ◽  
...  

The 4 properties of Chinese materia medica refer to cold, hot, warm, and cool. In the present study, the effects of the Coptis, the prepared aconite root, and dried ginger rhizome were compared with regard to the rectal and skin temperature changes of the related body surface acupuncture points (Dazhui, Zhiyang, Mingmen, Zhongwan, and Shenque). The investigation aimed to explore the thermal sensitive points, which can reflect the cold and hot properties of the Chinese herbs. This study showed that the prepared aconite root and dried ginger rhizome exhibited a warming effect on the body temperature, whereas the warming sensitive points were Zhongwan, Shenque, Dazhui, and Zhiyang. Coptis exhibited both a warming and a cooling effect on the body temperature, and the cooling sensitive point was Dazhui. The concomitant effect of these three Chinese herbs on the regulation of the body temperature was reflected by Dazhui. However, there are still some limitations and one-sidedness. For instance, the cold and hot property of some herbs cannot be fully reflected through relevant acupoints on the conception and governor vessels. More detecting sites such as ears and internal organs will be selected for further exploration of Chinese herbs’ cold and hot property.


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