Human body blood plasma

Uranium can enter the human body orally, by inhalation, and through the skin and mucous membranes. Uranium compounds, both soluble and insoluble, ate absorbed most readily from the lungs. In the blood of exposed animals, uranium occurs in two forms in equiUbrium with each other as a nondiffusible complex with plasma proteins and as a diffusible bicarbonate complex (242). 

Most of the tests that were developed for detection of cannabinoids in plants have shown that antibodies are specific for the cannabinoid structure. Because of this specifity these tests can be extensively applied for the detection of cannabinoids and metabolites in human body fluids such as plasma, urine, and oral fluids. Many different kits based on these methods were developed and they are commercially available, for example Oratect, Branan or Uplink, and OraSure. We must consider, however, that no humans have the same metabolite profile in their blood and that cross-reactivity may always occur [122,123]. Nevertheless, these tests offer a simple way of excluding most of the suspicious samples, but the results still have to be confirmed with a second method such as GC-MS [124,125]. 

Calcium exists in the human body as Ca(II) protein-bound and free Ca (II) ions (Dilana et al. 1994). For total extracellular Ca in plasma, serum and urine a definitive isotope dilution-mass spectrometry (ID-MS) method exist. Free Ca(II) in plasma/serum can be determined with PISE, but no definitive and reference methods exist. For Ca in faeces, tissue and blood flame atomic absorption (FAAS) is used widely. 

There are different types of cholinesterases in the human body, and they differ in their location in tissues, substrate affinity, and physiological function. The main ones are ACHE, present in nervous tissue and red blood cells (RBC-ACHE), and plasma cholinesterases (PCHE), present in glial cells, plasma, and liver. The physiological functions of RBC-ACHE and PCHE, if any, are unknown. 

Kokubo et al. [16,17] showed that the hydroxyapatite formation on the surfaces of bioactive materials in the living body can be reproduced even in an acellular protein-free simulated body fluid (SB F) with ion concentrations nearly equal to those of human blood plasma. This indicates that the hydroxyapatite layer is formed through chemical reaction of the bioactive glass with the surrounding body fluids. The formed layer consists of carbonated hydroxyapatite with small crystallites and low crystallinity, which is similar to bone hydroxyapatite. Hence the bioactivity of a material can be evaluated even in vitro by examining the hydroxyapatite formation on its surface in SBF. 

The abundance of tin in sea water is below 3 jxg 1 1. Typical abundance of tin in the human (adult) body is 17-130 mg tin distribution is 25% in skin and lipo-tissues 3.2% in red blood cell 0.8% in blood plasma the remainder in soft tissues9. 

Peptides in Human Urine (Skarzynski and Samecka-Keller), 5, 107 Protein Bound Iodine (Chaney), I, 82 Radioactive Iodine-131 in the Diagnosis of Hyperthyroidism, Blood Plasma Levels of (Silver), 1, 111 Transaminase Activities of Serum and Body Fluids, the Clinical Significance of Alterations in (Wroblew-ski), 1, 314... 

The human body has a number of different pH environments. For example, blood plasma has a rigorously controlled pH of 7.4 (see Box 4.9), the gastric juice is usually strongly acidic (pH from about 1 to 7), and urine can vary from about 4.8 to 7.5. It is possible to predict the qualitative effect of pH changes on the distribution of weakly acidic and basic dmgs, especially in relation to gastric absorption and renal excretion ... 

Human blood constitutes about 8% of the body s weight. It consists of cells and cell fragments in an aqueous medium, the blood plasma. The proportion of cellular elements, known as hematocrit, in the total volume is approximately 45%. 

A dose of 1 at 30 mg/kg increased the effects of intravenous doses of epinephrine at 5 g/kg and of dl-noreplnephrine at 10 ug/kg on both blood flow and blood pressure. Intravenous phenoxybenzamine at 15 mg/kg plus tolazollne at 2 mg/kg prevented almost completely the actions of I on blood pressure and blood flow Intravenous reserpine at 2 mg/kg increased markedly the effects of I at 30 mg/kg on blood pressure and peripheral resistance, but converted the usual immediate, small, temporary increase in blood flow into an immediate, small, temporary decrease. These various responses would be expected from either a mild sympathomimetic amine or an inhibitor of the breakdown of endogenous catecholamines Indeed, I at 10 M, was found to inhibit the monoamlneoxldase of the rat s liver. If the dose of I used in these experiments were distributed into the same fraction of the body water as that estimated for the human body,the concentration in the plasma would be about 9 times that stated above as the effective concentration for inhibiting the mono amine oxIdase. It is possible that inhibition of monoamlneoxldase by I plays a part in inducing the effects of the oxime on blood vessels and blood pressure. It is possible also that I interferes with reuptake of catecholamines by nerve endings this possibility seems not to have been explored. 

Once absorbed, foreign compounds may react with plasma proteins and distribute into various body compartments. In both neonates and elderly human subjects, both total plasma-protein and plasma-albumin levels are decreased. In the neonate, the plasma proteins may also show certain differences, which decrease the binding of foreign compounds, as will the reduced level of protein. For example, the drug lidocaine is only 20% bound to plasma proteins in the newborn compared with 70% in adult humans. The reduced plasma pH seen in neonates will also affect protein binding of some compounds as well as the distribution and excretion. Distribution of compounds into particular compartments may vary with age, resulting in differences in toxicity. For example, morphine is between 3 and 10 times more toxic to newborn rats than adults because of increased permeability of the brain in the newborn. Similarly, this difference in the blood-brain barrier underlies the increased neurotoxicity of lead in newborn rats. 

Alanine and Glutamine in the Blood Normal human blood plasma contains all the amino acids required for the synthesis of body proteins, but not in equal concentrations. Alanine and glutamine are present in much higher concentrations than any other amino acids. Suggest why. 

Fig. 11 Great Lakes food web, with approximate PCB concentrations. Note that PCB concentrations vary significantly among species in different locations, and among individuals of the same species. Concentrations in humans are estimated from the blood plasma concentrations in humans that eat Lake Michigan fish [314] and the distribution of PCBs in the body of rats [35]. See text for additional references...

Human blood is a complex mixture with a variety of functions provided by four major components red and white blood cells, platelets, and plasma. When a person begins to lose blood rapidly, the body can survive for at least a short time without the white blood cells (which are needed only to stave off infection), the platelets (of which there are large excesses in the body), and plasma (which can he replaced by an isotonic fluid, such as saline or Ringer s solution). But life cannot continue long with a replacement for the red blood cells. These are the cells that carry oxygen from the lungs to other cells, where it is used to carry out the metabolic processes that keep the body alive. 

Humans can be exposed to barium in the air, water, or food. Numerous studies exist that discuss the distribution of barium in the human body, but they do not always specify route of exposure. It is presumed that the majority of the barium intake is from the oral route. Barium occurs mostly (over 93%) in the bones and teeth of humans. Very little is found in blood plasma or soft tissues but, when it is detected in the organs, it is found in the eye, lungs, skin, and adipose tissue in humans at less than 1 % of total body weight (Schroeder et al. 1972). This information is supported by a number of studies (Bauer et al. 1957 Losee etal. 1974 Miller et al. 1985 Moloukhia and Ahmed 1979 Sowden 1958 Sowden and Stitch 1957 Sowden and Pirie 1958). 

The distribution of chromium(III) in humans was analyzed using a whole-body scintillation scanner, whole-body counter, and plasma counting. Six individuals given an intravenous injection of 51chromium(III) as chromium trichloride had >50% of the blood plasma chromium(ni) distributed to various body organs within hours of administration. The liver and spleen contained the highest levels. After 3 months, the liver contained half of the total body burden of chromium. The study results indicated a three-compartment model for whole-body accumulation and clearance of chromium(III). The half-lives were 0.5-12 hours for the fast component, 1-14 days for the medium component, and 3-12 months for the slow component (Lim et al. 1983). 

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