Osmotic and Ionic Regulation
Alan G. Heath in Water Pollution and Fish Physiology, 2018
The osmotic pressure of fish blood is mostly provided by inorganic salts and is approximately one third that of seawater, with marine fish having slightly more salt in their blood than freshwater species. The ionic fluxes for marine fish are approximately an order of magnitude greater than those for freshwater species. This reflects the greater permeability of the marine fish to these ions. Changes in osmoregulation in fish exposed to some stressor have been generally elucidated by measuring the blood plasma (or serum) electrolytes and/or total osmolality. Handling of a fish can, however, cause changes in osmoregulatory parameters independent of environmental pollutants, due to the phenomenon of handling diuresis, and changes in hormonal levels. Cadmium common pollutant appears to cause only moderate alterations in osmotic regulation, but specific ionic regulation, especially that of divalent cations, is quite sensitive to cadmium. Chlorine and Ozone are strong oxidizing agents which are quite toxic to fish.
The Formation of Thrombin
Roger L. Lundblad in The Chemical Biology of Thrombin, 2022
Thrombin can be found and formed in both the intravascular and extravascular space. Thrombin has a critical role in the hemostatic response within the intravascular space. The primary mechanism for the formation of thrombin for hemostasis in the intravascular space uses the prothrombinase complex; there may be some other mechanisms, such as the MASP protease mechanism, which might participate in disease states. Prothrombin, the precursor of thrombin, is one of the several vitamin K–dependent proteins present in blood plasma. The vitamin K–dependent proteins are characterized by requirement for vitamin K for synthesis of functional protein containing. Factor Xa is the enzyme responsible for the conversion of prothrombin to thrombin in the vascular system. It is possible factor Xa also functions in the extravascular space, but as shown later, there are mechanisms for the generation of thrombin in the extravascular space.
Physical Activity in Everyday Life
Robert Bridger in A Guide to Active Working in the Modern Office, 2019
The metabolic equivalent (MET) is a unit of physical activity that indicates the intensity of the activity. Physical inactivity shunts the delivery of lipids in the blood plasma away from the muscles to adipose tissue. According to the bed-rest studies, then, physical inactivity reduces the capacity of the body to use fat as an energy source; causes muscle loss; and causes resistance to insulin, elevated blood sugar levels, and elevated levels of triglycerides and cholesterol. A strong relationship of increased sitting time to mortality persisted, even among participants with relatively high levels of physical activity. People in the low-volume physical activity group had a 14 percent reduction in mortality and three-year increased life expectancy compared to those who were inactive. Overall the associations between sedentary time and adverse health outcomes were strong and consistent across the studies, even when physical activity was controlled for.
Microwave Blood Plasma Defroster
Published in Journal of Microwave Power and Electromagnetic Energy, 1991
A microwave blood plasma defroster capable of thawing up to four bags of frozen blood plasma at a time is described. The unit stops automatically when the plasma reaches a preset temperature, and all operating parameters are monitored for safety. Comparative testing showed that blood plasma thawed in this device was indistinguishable from plasma thawed in a water bath.
Blood plasma glucose regulation in Wahlberg’s epauletted fruit bat
Published in African Zoology, 2012
Babalwa R. Mqokeli, Colleen T. Downs
Frugivores feed on fruits and nectars that contain different types of sugars in different proportions, which provide these animals with energy. Wahlberg’s epauletted fruit bat (Epomophorus wahlbergi) has a high glucose intake irrespective of sugar concentration of nectar. It is not known how these bats regulate their blood plasma glucose concentrations in order to avoid the negative effects associated with hyperglycemia. Fruit bats have a high amount of sugar intake in a short period of time which could cause a glucose challenge and it is therefore necessary to determine whether these bats are able to regulate their blood plasma glucose concentrations within normal concentrations. This study investigated the diel variations in blood plasma glucose concentrations of E. wahlbergi. Epomophorus wahlbergi‘s blood plasma glucose concentration was lower (5.24 ± 0.38 mmol/l) at 18:00 before feeding and increased during/after feeding (8.19 ± 1.24 mmol/l) but bats appeared to regulate it within limits. Their range in concentrations was higher than the normal mammalian blood plasma glucose concentrations range. Consequently these bats appear to regulate their blood plasma glucose concentration, although at a range higher than normal mammalian levels, and thus reduce the negative consequences associated with hyperglycemia.
Determination of Organochlorine Residues in Maternal and Cord Blood Plasma
Published in International Journal of Environmental Analytical Chemistry, 1988
Organochlorine pesticide (OCP) residues determined in seventy-seven maternal and forty-eight cord blood plasma samples showed mean levels of total p,p'-DDT in maternal (pregnant), maternal (non-pregnant) and cord blood plasma to be 14.9, 6.8 and 7.6 mg/kg fat respectively. Mean levels of total HCH for the three sets of samples were 5.1, 2.4 and 1.5mg/kg fat respectively while those for HCB were 0.6, 0.4 and 0.4 mg/kg fat respectively. The level of OCPs in the cord blood plasma reflects the degree of transplacental transfer of these contaminants from the mother to the developing foetus. The high levels of contaminants in the blood plasma of pregnant women could be attributable to more intensive use of aerosol insecticides during pregnancy.
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