Blood normal components

Nieda M, Nicol A, Denning-Kendall P, Sweetenham J, Bradley B, Hows J. Endothelial cell precursors are normal components of human umbilical cord blood. Br J Haematol 1997 98 775-777. 

Samples Obtained from Biological Fluids As illustrated in Figure 5.1, biological fluids, which also have two compartments, are placed in group I. Such fluids include blood (often classified as a tissue), urine, semen, tears, and saliva. Many of these fluids contain cells as a normal component, while in others the cells represent a contamination. Fluids like saliva that contact the outside and, when collected, often contain microbes, are examples of contaminated materials. Sometimes such microbes are the result of the collection procedure, and their numbers can often be controlled by careful technique. At other times, as is the case with urine, their presence can indicate an underlying disease process. In any case, the study of enzymes from such fluids again requires the separation of the two compartments. 

Manganese is a normal component of human and animal tissues and fluids. In humans, most tissue concentrations range between 0.1 and 1 pg manganese/g wet weight (Sumino et al. 1975 Tipton and Cook 1963), with the highest levels in the liver, pancreas, and kidney and the lowest levels in bone and fat (see Table 2-3). Manganese levels in the blood, urine, and serum of healthy, unexposed subjects living in the... 

Blood normally circulates through endothelium-lined blood vessels. When a blood vessel is severed, a blood clot (called a thrombus, which is formed by the process of thrombosis) forms as part of hemostasis, the physiologic response that stops bleeding. Blood clots also form to repair damage to the endothelial lining, in which components of the subendothelial layer become accessible to plasma proteins. 

Products and Uses Produced from milk by the action of lactic acid bacteria when milk is fermented to make cheese. It is also found in other sour foods such as sauerkraut, fermented meats, molasses and is a preservative with some pickled foods such as pearl onions and olives. It is also a normal component of our body. It is produced be muscle activity and normal metabolism and is in our blood and urine. It is a component of all plant and animal tissues and it is impossible to keep out of our diet. Useful as an acid, antimicrobial agent, curing... 

Cholesterol, shown in Figure 24.11, is a biochemically important alcohol. The OH group forms only a small component of this molecule, so cholesterol is only slightly soluble in water (0.26 g per 100 mL of H2O). Cholesterol is a normal component of our bodies when present in excessive amounts, however, it may precipitate from solution. It precipitates in the gallbladder to form crystalline lumps called gallstones. It may also precipitate against the walls of veins and arteries and thus contribute to high blood pressure and other cardiovascular problems. 

Full details of this work were pubHshed (6) and the processes, or variants of them, were introduced in a number of other countries. In the United States, the pharmaceutical industry continued to provide manufacturing sites, treating plasma fractionation as a normal commercial activity. In many other countries processing was undertaken by the Red Cross or blood transfusion services that emerged following Wodd War II. In these organisations plasma fractionation was part of a larger operation to provide whole blood, blood components, and speciaUst medical services on a national basis. These different approaches resulted in the development of two distinct sectors in the plasma fractionation industry ie, a commercial or for-profit sector based on paid donors and a noncommercial or not-for-profit sector based on unpaid donors. 

Histamine in the Blood. After its release, histamine diffuses rapidly into the blood stream and surrounding tissues (12). Histamine appears in blood within 2.5 min after its release, peaks at 5 min, and returns to baseline levels by 15 to 30 min. In humans, the diurnal mean of plasma histamine levels is 0.13 ng/g. In urine, elevations of histamine or metaboUtes are more prolonged than plasma elevations. Consequendy, abnormahties are more easily detected by urinary histamine assay. About one-half of the histamine in normal blood is in basophils, one-third in eosinophils, and one-seventh in neutrophils the remainder is distributed among all the other blood components. Increases in blood histamine levels occur in several pathological... 

Fiber components are the principal energy source for colonic bacteria with a further contribution from digestive tract mucosal polysaccharides. Rate of fermentation varies with the chemical nature of the fiber components. Short-chain fatty acids generated by bacterial action are partiaUy absorbed through the colon waU and provide a supplementary energy source to the host. Therefore, dietary fiber is partiaUy caloric. The short-chain fatty acids also promote reabsorption of sodium and water from the colon and stimulate colonic blood flow and pancreatic secretions. Butyrate has added health benefits. Butyric acid is the preferred energy source for the colonocytes and has been shown to promote normal colonic epitheUal ceU differentiation. Butyric acid may inhibit colonic polyps and tumors. The relationships of intestinal microflora to health and disease have been reviewed (10). 

Hurst (19) discusses the similarity in action of the pyrethrins and of DDT as indicated by a dispersant action on the lipids of insect cuticle and internal tissue. He has developed an elaborate theory of contact insecticidal action but provides no experimental data. Hurst believes that the susceptibility to insecticides depends partially on the cuticular permeability, but more fundamentally on the effects on internal tissue receptors which control oxidative metabolism or oxidative enzyme systems. The access of pyrethrins to insects, for example, is facilitated by adsorption and storage in the lipophilic layers of the epicuticle. The epicuticle is to be regarded as a lipoprotein mosaic consisting of alternating patches of lipid and protein receptors which are sites of oxidase activity. Such a condition exists in both the hydrophilic type of cuticle found in larvae of Calliphora and Phormia and in the waxy cuticle of Tenebrio larvae. Hurst explains pyrethrinization as a preliminary narcosis or knockdown phase in which oxidase action is blocked by adsorption of the insecticide on the lipoprotein tissue components, followed by death when further dispersant action of the insecticide results in an irreversible increase in the phenoloxidase activity as a result of the displacement of protective lipids. This increase in phenoloxidase activity is accompanied by the accumulation of toxic quinoid metabolites in the blood and tissues—for example, O-quinones which would block substrate access to normal enzyme systems. The varying degrees of susceptibility shown by different insect species to an insecticide may be explainable not only in terms of differences in cuticle make-up but also as internal factors associated with the stability of oxidase systems. 

The Newborn and the Laboratory. The wellbeing of the pre-mature infant can be ascertained by measuring blood pH, electrolytes and other blood components on a routine basis. The maintenance of these infants electrolyte balance and normal pH is shown in Figure 3. An infant placed on a high protein diet milk formula developed an acidosis, and when brought to normal pH... 

Along with an effective electrolyte and screening program for genetic disease, the laboratory of Neonatology needs to have the capability of analyzing for other components in blood serum, which aid in the diagnosis of disease. These include such determinations as alkaline phosphatase, and various other enzymes, creatinine, uric acid and a host of other components which are normally assayed by the main clinical laboratory. 

Natelson, S. Penniall, R. Crawford, W. L. and Munsey, F. A. Noncasein protein to casein ration of feeding formulas. Effect on blood component levels in normal infants. Am. J. Dis. Child. (1955), 89,... 

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