Prey handling using whole-body fluid dynamics in batoids

Zoology ◽  
2012 ◽  
Vol 115 (1) ◽  
pp. 47-57 ◽  
Author(s):  
Cheryl D. Wilga ◽  
Anabela Maia ◽  
Sandra Nauwelaerts ◽  
George V. Lauder
Keyword(s):  
Fluid Dynamics ◽  
Body Fluid ◽  
Whole Body ◽  
Prey Handling

Estrogen-related receptor γ2 controls NaCl uptake to maintain ionic homeostasis

2021 ◽  
Author(s):  
Shang-Wu Shih ◽  
Jia-Jiun Yan ◽  
Yi-Hsing Wang ◽  
Yi-Ling Tsou ◽  
Ling Chiu ◽  
...  
Keyword(s):  
Mrna Expression ◽  
Body Fluid ◽  
Whole Body ◽  
Ionic Homeostasis ◽  
Ion Regulation ◽  
Expression Levels ◽  
Morpholino Knockdown ◽  
Oryzias Melastigma ◽  
Euryhaline Teleost

Estrogen-related receptors (ERRs) are known to function in mammalian kidney as key regulators of ion transport-related genes; however, a comprehensive understanding of the physiological functions of ERRs in vertebrate body fluid ionic homeostasis is still elusive. Here, we used medaka (Oryzias melastigma), a euryhaline teleost, to investigate how ERRs are involved in ion regulation. After transferring medaka from hypertonic seawater to hypotonic freshwater (FW), the mRNA expression levels of errγ2 were highly upregulated, suggesting that ERRγ2 may play a crucial role in ion uptake. In situ hybridization and immunofluorescence staining showed that errγ2 was specifically expressed in ionocytes, the cells responsible for Na+/Cl- transport. In normal FW, ERRγ2 morpholino knockdown caused reductions in the mRNA expression of Na+/Cl- cotransporter (NCC), the number of NCC ionocytes, Na+/Cl- influxes of ionocytes, and whole-body Na+/Cl- contents. In FW with low Na+ and low Cl-, the expression levels of mRNA for Na+/H+ exchanger 3 (NHE3) and NCC were both decreased in ERRγ2 morphants. Treating embryos with DY131, an agonist of ERRγ, increased the whole-body Na+/Cl- contents and ncc mRNA expression in ERRγ2 morphants. As such, medaka ERRγ2 may control Na+/Cl- uptake by regulating ncc and/or nhe3 mRNA expression and ionocyte number, and these regulatory actions may be subtly adjusted depending on internal and external ion concentrations. These findings not only provide new insights into the underpinning mechanism of actions of ERRs, but also enhance our understanding of their roles in body fluid ionic homeostasis for adaptation to changing environments during vertebrate evolution.

Body fluid responses of heat-tolerant and intolerant men to work in a hot wet environment

1976 ◽  
Vol 40 (1) ◽  
pp. 55-59 ◽  
Author(s):  
L. C. Senay ◽  
R. Kok
Keyword(s):  
Fluid Dynamics ◽  
Oxygen Consumption ◽  
South African ◽  
Heat Tolerance ◽  
Body Fluid ◽  
Large Population ◽  
Work Period ◽  
Blood Constituent ◽  
Heat Tolerant ◽  
Capillary Walls

Acclimatization to heat before proceeding underground is a requirement for each South African mine laborer. Certain individuals among this large population cannot be acclimatized to heat (33.3 degrees C db, 31.7 degrees C wb) and are classified as heat intolerant. In this study certain body fluid responses to heat and work were compared between a group of 19 heat-tolerant (HT) and of 15 heat-intolerant (HI) subjects. To the factors known to affect heat tolerance such as age, weight, and oxygen consumption must now be added differences in body fluid responses. The HI group of subjects failed to hemodilute to the same degree as the HT group though working at the same relative work loads (30% and 50% VO2 max). As the 4-h work period (33.3 degrees C db, 31.7 degrees C wb) continued, the HI group did not maintain hemodilution in spite of the lower absolute work loads, sweat rates, and water deficits suffered by this group. From analysis of blood constituent changes it was suggested that the reason for the differences noted in body fluid dynamics concerned plasma protein equilibrium across capillary walls as well as the protein population of interstitial spaces.

scholarly journals Hydration Status Is Associated with Aortic Stiffness, but Not with Peripheral Arterial Stiffness, in Chronically Hemodialysed Patients

2015 ◽  
Vol 2015 ◽  
pp. 1-11 ◽  
Author(s):  
Daniel Bia ◽  
Cintia Galli ◽  
Rodolfo Valtuille ◽  
Yanina Zócalo ◽  
Sandra A. Wray ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Arterial Stiffness ◽  
Body Fluid ◽  
Fluid Management ◽  
Blood Pressure Level ◽  
Whole Body ◽  
Volume Status ◽  
Hydration Status ◽  
Fluid Status ◽  
Peripheral Arterial

Background. Adequate fluid management could be essential to minimize high arterial stiffness observed in chronically hemodialyzed patients (CHP).Aim. To determine the association between body fluid status and central and peripheral arterial stiffness levels.Methods. Arterial stiffness was assessed in 65 CHP by measuring the pulse wave velocity (PWV) in a central arterial pathway (carotid-femoral) and in a peripheral pathway (carotid-brachial). A blood pressure-independent regional arterial stiffness index was calculated using PWV. Volume status was assessed by whole-body multiple-frequency bioimpedance. Patients were first observed as an entire group and then divided into three different fluid status-related groups: normal, overhydration, and dehydration groups.Results. Only carotid-femoral stiffness was positively associated (P<0.05) with the hydration status evaluated through extracellular/intracellular fluid, extracellular/Total Body Fluid, and absolute and relative overhydration.Conclusion. Volume status and overload are associated with central, but not peripheral, arterial stiffness levels with independence of the blood pressure level, in CHP.

BIOKINETIC MODEL DEVELOPMENT OF RADIOIODINE-131 VIA IN VIVO GAMMA CAMERA/8-SLICE CT TECHNIQUE: CASE-CONTROL STUDY OF FELINE HYPERTHYROIDISM

2018 ◽  
Vol 18 (08) ◽  
pp. 1840035
Author(s):  
CHIH-FENG CHEN ◽  
CHAO-HSUN CHUANG ◽  
PAO-CHEN TANG ◽  
NENG-CHUNG TSENG ◽  
LUNG-FA PAN ◽  
...  
Keyword(s):  
Body Fluid ◽  
Gamma Camera ◽  
Case Control Study ◽  
Case Control ◽  
Time Dependent ◽  
Whole Body ◽  
Biokinetic Model ◽  
Stomach Body ◽  
Control Study

Objectives: A biokinetic model of iodine in the thyroid was developed and applied to a case-control study of hyperthyroid cat undertaken the NaI-131 dose administration using a gamma camera/8-slice CT with the in vivo study. Methods: The case-control hyperthyroid cats were administered 55.5 or 3.7[Formula: see text]MBq of I-131 radioactive solution and continuously surveyed by a gamma camera. The scan schedule was preset as 5- or 10-min counting per each hour from the initial time to the sixth hour, then on the 24th, 48th and 72nd hours, respectively. An in-house developed program run in the MATLAB was applied to evaluate the biokinetic model of iodine in the thyroid, in compliance with the ICRP-30 report regulations. The model was defined by five compartments (namely: stomach, body fluid, thyroid, whole body, and excretion) and allowed one to simulate the variations of time-dependent I-131 radioactive concentration among various compartments of each study subject. The numerical simulation via MATLAB was compiled with the empirical evaluation to optimize the time-dependent concentration of I-131 within the above compartments. Results: The derived biological half-life values for stomach, body fluid, thyroid, whole body, and excretion, respectively, were as follows: 17, 3, 10, 5 and 140[Formula: see text]h for hyperthyroid cat, 18, 1, 8, 2, and 40[Formula: see text]h for control #1 cat, and 22, 2, 12, 4, and 20[Formula: see text]h for control #2 cat. The cumulative radioactive doses from both gamma-ray and beta particles were assessed via a simplified algorithm as 0.135, 0.0082, and 0.005 Gy, for hyperthyroid cat, control #1, and control #2 ones, respectively. Conclusion: The derived biokinetic model was found to be helpful in the evaluation of the metabolic mechanism in case of feline hyperthyroidism. The revealed deviations from available human biomodels can be used for refining the radioiodine treatment of pets with hyperthyroidism.

Cold-water acclimation does not modify whole-body fluid regulation during subsequent cold-water immersion

2004 ◽  
Vol 92 (1-2) ◽  
pp. 56-61 ◽  
Author(s):  
J. M. Stocks ◽  
M. J. Patterson ◽  
D. E. Hyde ◽  
A. B. Jenkins ◽  
K. D. Mittleman ◽  
...  
Keyword(s):  
Body Fluid ◽  
Cold Water ◽  
Water Immersion ◽  
Cold Water Immersion ◽  
Whole Body ◽  
Fluid Regulation ◽  
Body Fluid Regulation

Segment-specific resistivity improves body fluid volume estimates from bioimpedance spectroscopy in hemodialysis patients

2006 ◽  
Vol 100 (2) ◽  
pp. 717-724 ◽  
Author(s):  
F. Zhu ◽  
M. K. Kuhlmann ◽  
G. A. Kaysen ◽  
S. Sarkar ◽  
C. Kaitwatcharachai ◽  
...  
Keyword(s):  
Gold Standard ◽  
Total Body Water ◽  
Body Fluid ◽  
Hemodialysis Patients ◽  
Fluid Volume ◽  
Whole Body ◽  
Bioimpedance Spectroscopy ◽  
Specific Resistivity ◽  
Body Fluid Volume ◽  
Total Body

Discrepancies in body fluid estimates between segmental bioimpedance spectroscopy (SBIS) and gold-standard methods may be due to the use of a uniform value of tissue resistivity to compute extracellular fluid volume (ECV) and intracellular fluid volume (ICV). Discrepancies may also arise from the exclusion of fluid volumes of hands, feet, neck, and head from measurements due to electrode positions. The aim of this study was to define the specific resistivity of various body segments and to use those values for computation of ECV and ICV along with a correction for unmeasured fluid volumes. Twenty-nine maintenance hemodialysis patients (16 men) underwent body composition analysis including whole body MRI, whole body potassium (40K) content, deuterium, and sodium bromide dilution, and segmental and wrist-to-ankle bioimpedance spectroscopy, all performed on the same day before a hemodialysis. Segment-specific resistivity was determined from segmental fat-free mass (FFM; by MRI), hydration status of FFM (by deuterium and sodium bromide), tissue resistance (by SBIS), and segment length. Segmental FFM was higher and extracellular hydration of FFM was lower in men compared with women. Segment-specific resistivity values for arm, trunk, and leg all differed from the uniform resistivity used in traditional SBIS algorithms. Estimates for whole body ECV, ICV, and total body water from SBIS using segmental instead of uniform resistivity values and after adjustment for unmeasured fluid volumes of the body did not differ significantly from gold-standard measures. The uniform tissue resistivity values used in traditional SBIS algorithms result in underestimation of ECV, ICV, and total body water. Use of segmental resistivity values combined with adjustment for body volumes that are neglected by traditional SBIS technique significantly improves estimations of body fluid volume in hemodialysis patients.

scholarly journals Body Fluid Dynamics: Back to the Future

2011 ◽  
Vol 22 (12) ◽  
pp. 2166-2181 ◽  
Author(s):  
Gautam Bhave ◽  
Eric G. Neilson
Keyword(s):  
Fluid Dynamics ◽  
Body Fluid ◽  
The Future

Nutritional assessment: Whole body impedance and body fluid compartments

1980 ◽  
Vol 2 (1) ◽  
pp. 72-80 ◽  
Author(s):  
R. Gregg Settle ◽  
Kenneth R. Foster ◽  
Benjamin R. Epstein ◽  
James L. Mullen
Keyword(s):  
Body Fluid ◽  
Nutritional Assessment ◽  
Whole Body ◽  
Body Fluid Compartments ◽  
Body Impedance ◽  
Fluid Compartments

Effects of immersion water temperature on whole-body fluid distribution in humans

2004 ◽  
Vol 182 (1) ◽  
pp. 3-10 ◽  
Author(s):  
J. M. Stocks ◽  
M. J. Patterson ◽  
D. E. Hyde ◽  
A. B. Jenkins ◽  
K. D. Mittleman ◽  
...  
Keyword(s):  
Water Temperature ◽  
Body Fluid ◽  
Whole Body ◽  
Fluid Distribution

Whole Body Fluid and Electrolyte Assays in “Normal” Volunteers

1993 ◽  
pp. 63-66
Author(s):  
D. Walter Thomas ◽  
John L. Birks ◽  
Parvaiz A. Ali ◽  
Hilary Jenkins ◽  
Jack Dutton ◽  
...  
Keyword(s):  
Body Fluid ◽  
Whole Body ◽  
Normal Volunteers
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