scholarly journals The Role of Blood in Regulating Body Heat in Bovines

2021 ◽  
Vol 2 (1) ◽  
pp. 61-75
Keyword(s):  
Body Heat

scholarly journals Why Only People and Apes are Ill with Common Cold? The Possible Role of Chromosomal Q-Heterochromatin Variability

2016 ◽  
Vol 6 (1) ◽  
pp. 11
Author(s):  
A. I. Ibraimov
Keyword(s):  
Common Cold ◽  
Standard Theory ◽  
Negative Consequences ◽  
Circulatory Disturbance ◽  
Sickness Rate ◽  
The Common ◽  
And Gender ◽  
Virus Strains ◽  
Body Heat

<p class="1Body">Common cold (CC) is referred to the most widespread human illnesses and affects people all over the globe. Till now there is no standard theory explaining the development mechanism(s) of СС. The etiology of the CC is known - over 200 virus strains are implicated in the cause of the common cold; the rhinoviruses are the most common. As for pathogenesis, it is conventional, that cold plays the important role in development of СС. It is believed that cooling causes blood circulatory disturbance and permeability of vessels that consequently deteriorates the tissue nutrition and its resistance against infectious agents, and its resistibility in relation to infection. It is also known that the CC sickness rate is affected by the age (children get sick more often than adults) and gender (male individuals are more susceptible to CC than females, regardless of their age). Among the issues that have not received an answer is another question: why CC affects only upon humans and apes? It is hypothesized that the cause of these higher primates susceptibility to CC is the highest level of their body heat conductivity in the animal world. Just this circumstance contributes to the rapid and deep cooling of the bodies of people and apes when it is cold, with all the ensuing negative consequences for the organism.</p>

A note on canary coloration of wool in Ghokla sheep as influenced by restricted frequency of access to water

1978 ◽  
Vol 90 (3) ◽  
pp. 641-642
Author(s):  
M. Singh ◽  
T. More
Keyword(s):  
Water Intake ◽  
Physiological Stress ◽  
Nutritional Deficiency ◽  
Adaptive Mechanism ◽  
Access To Water ◽  
Yellow Coloration ◽  
Cutaneous Evaporation ◽  
Body Heat ◽  
Indian Sheep

Yellowing of wool as a function of physiological stress caused by nutritional deficiency in the feed of sheep (Das, 1965) though not confirmed by subsequent studies (Singh et al. 1977) evoked interest in the role of physiological stress in causing canary staining of wool. Restricted water intake as is generally the case with sheep in arid or even semiarid regions during summer, imposes considerable physiological stress. Furthermore, canary coloration is thought to be a sequel to an adaptive mechanism to hot and humid conditions in Indian sheep which have a greater reliance on cutaneous evaporation for dissipating body heat (Acharaya & Singh, 1976). It was, therefore, decided to study the influence, if any, of restricting access to water on the canary coloration of wool (non-scourable yellow coloration of the autumn clip) in the stain-susceptible Chokla sheep

scholarly journals Dysfunctional TRPM8 signalling in the vascular response to environmental cold in ageing.

2021 ◽  
Author(s):  
Dibesh Thapa ◽  
Joao de Sousa Valente ◽  
Brentton Barrett ◽  
Fulye Argunhan ◽  
Sheng Y. Lee ◽  
...  
Keyword(s):  
Transient Receptor Potential ◽  
Mouse Skin ◽  
Receptor Potential ◽  
Vascular Response ◽  
Trpm8 Gene ◽  
Cold Sensitive ◽  
Pharmacological Blockade ◽  
Transient Receptor ◽  
Body Heat

Ageing is associated with increased vulnerability to environmental cold exposure. Previously, we identified the role of the cold-sensitive transient receptor potential (TRP) A1, M8 receptors as vascular cold sensors in mouse skin. We hypothesised that this dynamic cold-sensor system may become dysfunctional in ageing. We show that behavioural and vascular responses to skin local environmental cooling are impaired with even moderate ageing, with reduced TRPM8 gene/protein expression especially. Pharmacological blockade of the residual TRPA1/TRPM8 component substantially diminished the response in aged, compared with young mice. This implies the reliance of the already reduced cold-induced vascular response in ageing mice on remaining TRP receptor activity. Moreover, sympathetic-induced vasoconstriction was reduced with downregulation of the α2c adrenoceptor receptor in ageing. The cold-induced vascular response is important for sensing cold and retaining body heat and health. These findings reveal that cold sensors, essential for this neurovascular pathway, decline as ageing onsets.

scholarly journals Additive effects of heating and exercise on baroreflex control of heart rate in healthy males

2017 ◽  
Vol 123 (6) ◽  
pp. 1555-1562 ◽  
Author(s):  
Tiago Peçanha ◽  
Cláudia L. M. Forjaz ◽  
David. A. Low
Keyword(s):  
Heart Rate ◽  
Heat Stress ◽  
Baroreflex Sensitivity ◽  
Whole Body ◽  
Additive Effects ◽  
Passive Heating ◽  
Baroreflex Control ◽  
Rr Intervals ◽  
Body Heat

This study assessed the additive effects of passive heating and exercise on cardiac baroreflex sensitivity (cBRS) and heart rate variability (HRV). Twelve healthy young men (25 ± 1 yr, 23.8 ± 0.5 kg/m2) randomly underwent two experimental sessions: heat stress (HS; whole body heat stress using a tube-lined suit to increase core temperature by ~1°C) and normothermia (NT). Each session was composed of a preintervention rest (REST1); HS or NT interventions; postintervention rest (REST2); and 14 min of cycling exercise [7 min at 40%HRreserve (EX1) and 7 min at 60%HRreserve (EX2)]. Heart rate and finger blood pressure were continuously recorded. cBRS was assessed using the sequence (cBRSSEQ) and transfer function (cBRSTF) methods. HRV was assessed using the indexes standard deviation of RR intervals (SDNN) and root mean square of successive RR intervals (RMSSD). cBRS and HRV were not different between sessions during EX1 and EX2 (i.e., matched heart rate conditions: EX1 = 116 ± 3 vs. 114 ± 3 and EX2 = 143 ± 4 vs. 142 ± 3 beats/min but different workloads: EX1 = 50 ± 9 vs. 114 ± 8 and EX2 = 106 ± 10 vs. 165 ± 8 W; for HS and NT, respectively; P < 0.01). However, when comparing EX1 of NT with EX2 of HS (i.e., matched workload conditions but with different heart rates), cBRS and HRV were significantly reduced in HS (cBRSSEQ = 1.6 ± 0.3 vs. 0.6 ± 0.1 ms/mmHg, P < 0.01; SDNN = 2.3 ± 0.1 vs. 1.3 ± 0.2 ms, P < 0.01). In conclusion, in conditions matched by HR, the addition of heat stress to exercise does not affect cBRS and HRV. Alternatively, in workload-matched conditions, the addition of heat to exercise results in reduced cBRS and HRV compared with exercise in normothermia. NEW & NOTEWORTHY The present study assessed cardiac baroreflex sensitivity during the combination of heat and exercise stresses. This is the first study to show that prior whole body passive heating reduces cardiac baroreflex sensitivity and autonomic modulation of heart rate during exercise. These findings contribute to the better understanding of the role of thermoregulation on cardiovascular regulation during exercise.

scholarly journals Cell thermoregulation hypothesis: its origin, material basis, mechanisms and meaning

2019 ◽  
pp. 114-123
Author(s):  
Ibraimov AI
Keyword(s):  
Cell Biology ◽  
Interphase Nucleus ◽  
Chromosome Structure ◽  
Condensed Chromatin ◽  
Human Populations ◽  
Material Basis ◽  
A Cell ◽  
Higher Eukaryotes ◽  
Body Heat

The accumulated knowledge about the chromosome structure, redundant DNA and an interphase nucleus inevitably raises, at least, two questions: (1) Why are there so much non-coding DNAs in chromosomes of higher eukaryotes and (2) what is the role of their organization in interphase nucleus on cellular function? These questions in cell biology are attracting increased attention as the genomes of higher eukaryotes are being sequenced. Based on investigations of chromosomal heterochromatin regions variability in human populations, condensed chromatin (CC), interphase nucleus and redundant non-coding DNAs in the genome, an attempt is made to justify the view of possible participation of CC in cell thermoregulation. CC, being the densest domains in a cell, apparently conducts heat between the cytoplasm and nucleus when there is a difference in temperature between them. Keywords: Cell Thermoregulation; Condensed Chromatin; Q-heterochromatin; C-heterochromatin; Human Body Heat Conductivity; Human Adaptation

How do ectoparasitic nycteribiids locate their bat hosts?

Parasitology ◽  
2008 ◽  
Vol 135 (10) ◽  
pp. 1205-1213 ◽  
Author(s):  
S. I. LOURENÇO ◽  
J. M. PALMEIRIM
Keyword(s):  
Carbon Dioxide ◽  
Effective Strategy ◽  
Sensory Cues ◽  
Specific Host ◽  
Myotis Myotis ◽  
Adult Lives ◽  
Body Heat

SUMMARYNycteribiids (Diptera: Nycteribiidae) are specific haematophagous ectoparasites of bats, which spend nearly all their adult lives on hosts. However, females have to leave bats to deposit their larva on the walls of the roosts, where they later emerge as adult flies. Nycteribiids had thus to evolve efficient sensorial mechanisms to locate hosts from a distance. We studied the sensory cues involved in this process, experimentally testing the role of specific host odours, and general cues such as carbon dioxide, body heat, and vibrations. As models we used two nycteribiids (Penicillidia conspicua and Penicillidia dufourii) and their primary bat hosts (Miniopterus schreibersii and Myotis myotis, respectively). Carbon dioxide was the most effective cue activating and orientating the responses of nycteribiids, followed by body heat and body odours. They also responded to vibration, but did not orientate to its source. In addition, sensory cues combined (carbon dioxide and body heat) were more effective in orientating nycteribiids than either cue delivered alone. Results suggest that nycteribids have some capacity to distinguish specific hosts from a distance, probably through their specific body odours. However, the strong reliance of nycteribiids on cues combined indicates that they follow these to orientate to nearby multispecies bat clusters, where the chances of finding their primary hosts are high. The combination of sensory cues seems therefore an effective strategy used by nycteribiids to locate bat hosts at a distance.

Nitric oxide concentration increases in the cutaneous interstitial space during heat stress in humans

2003 ◽  
Vol 94 (5) ◽  
pp. 1971-1977 ◽  
Author(s):  
D. L. Kellogg ◽  
J. L. Zhao ◽  
C. Friel ◽  
L. J. Roman
Keyword(s):  
Nitric Oxide ◽  
Heat Stress ◽  
Whole Body ◽  
Microdialysis Probe ◽  
Doppler Flowmetry ◽  
Oxide Concentration ◽  
Nitric Oxide Concentration ◽  
Whole Body Heat Stress ◽  
Body Heat

To examine the role of nitric oxide (NO) in cutaneous active vasodilation, we measured the NO concentration from skin before and during whole body heat stress in nine healthy subjects. A forearm site was instrumented with a NO-selective, amperometric electrode and an adjacent intradermal microdialysis probe. Skin blood flow (SkBF) was monitored by laser-Doppler flowmetry (LDF). NO concentrations and LDF were measured in normothermia and heat stress. After heat stress, a solution of ACh was perfused through the microdialysis probe to pharmacologically generate NO and verify the electrode's function. During whole body warming, both SkBF and NO concentrations began to increase at the same internal temperature. Both SkBF and NO concentrations increased during heat stress (402 ± 76% change from LDF baseline, P < 0.05; 22 ± 5% change from NO baseline, P < 0.05). During a second baseline condition after heat stress, ACh perfusion led to increases in both SkBF and NO concentrations (496 ± 119% change from LDF baseline, P < 0.05; 16 ± 10% change from NO baseline, P < 0.05). We conclude that NO does increase in skin during heat stress in humans, attendant to active vasodilation. This result suggests that NO has a role beyond that of a permissive factor in the process; rather, NO may well be an effector of cutaneous vasodilation during heat stress.

scholarly journals The role of gut tissue in the energy metabolism of growing lambs fed forage or concentrate diets

2001 ◽  
Vol 86 (2) ◽  
pp. 257-264 ◽  
Author(s):  
Esther J. Finegan ◽  
Jock G. Buchanan-Smith ◽  
Brian W. McBride
Keyword(s):  
Heat Loss ◽  
Metabolizable Energy ◽  
Whole Body ◽  
Forage Legume ◽  
Group Of Seven ◽  
Grass Silage ◽  
Relative Contribution ◽  
Body Heat

The role of the gastrointestinal tract (GIT) in explaining the less efficient utilization of metabolizable energy (ME) in growing lambs fed forage rather than concentrate-based diets was investigated by feeding forage (legume–grass silage) and concentrate (whole shelled maize) diets, at isoenergetic intakes (ME basis), using five groups of lambs. One group of seven lambs was an initial slaughter group and of the two groups (eight lambs per group) fed each diet, one group was fed for 8 weeks, whereas the other group was fed for 16 weeks. All lambs were slaughtered between 18·5 and 20 h following their last meal. Retained energy (as a percentage of ME intake) was higher (concentrate-fed 28, forage-fed 17; P<0·001) for the concentrate-fed animals. Weight-specific mucosal O2 uptake (ml/g DM per h), measured in vitro, was 37 % higher for the forestomach (reticulum, rumen and omasum) and small intestine (jejunum) than for the abomasum and large intestine (caecum and colon), but there was no evidence for a diet effect (except colon; forage-fed 5·3, concentrate-fed 4·2; P=0·036). Total GIT heat loss was estimated as 14 (forage-fed) and 18 (concentrate-fed) % of the whole-body heat loss. Although the GIT did not contribute to increased thermogenesis in the forage-fed lambs in the present study, greater relative contribution of GIT tissue to whole-body mass, i.e. GIT as a percentage of empty-body weight(forage 7·6, concentrate 6·6; P<0·001) in the forage-fed animals supports a role for the GIT in contributing to higher thermogenesis observed in ruminants fed forage as opposed to concentrate diets.

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