Serum processing

Johnson has described a method for the estimation of physostigmine in the salicylate for the determination of minute amounts of the alkaloid Ellis, Plaehte and Straus have devised processes depending on (a) inhibition of serum choline-esterase by the alkaloid, or (b) measurement of the colour intensity produced by the conversion of physostigmine to rubreserine in an alkaline medium. i ... 

Universal anti-Rh sera deprived of anti-A or B-antibodies were prepared by contacting A and B-immunoadsorbents with human blood sera. To achieve zero titer in the Coombs agglutination test a portion of immunoadsorbent (80-160 mg) proportional to the initial serum titer (1 8-1 64, 1 ml) is required. The incorporation of A-immunoadsorbent into anti-B sera did not interfere with their titer and vice versa, Under the same circumstances an anti-Rh serum titer is lowered by one step or remains unchanged [125], Properties of this composite sorbent are therefore promising for its use in extracorporal hemisorption processes. 

Acute phase reactants (e.g., C-reactive protein) are proteins that increase during inflammation and are deposited in damaged tissues. They were first discovered in the serum, but are now known to be involved in inflammatory processes in the brain (e.g., found in the brain of Alzheimer patients and associated with amyloid plaques). 

Andry, M. C. Levy, M. C. (1997). In vitro degradation of serum albumin microcapsules Effect of process variables. International Journal of Pharmaceutics, Vol. 152, 2, (Jime 1997), pp. (145-151), ISSN 0378-5173... 

The thyroid is able to concentrate T against a strong electrochemical gradient. This is an energy-dependent process and is linked to the Na -K ATPase-dependent thyroidal T transporter. The ratio of iodide in thyroid to iodide in serum (T S ratio) is a reflection of the activity of this transporter. This activity is primarily controlled by TSH and ranges from 500 1 in animals chronically stimulated with TSH to 5 1 or less in hy-pophysectomized animals (no TSH). The T S ratio in humans on a normal iodine diet is about 25 1. 

Vitamin D3 enters the skin microcirculation after formation and is bound to a specific globulin in the serum. It and vitamin D2 which is absorbed from the gut are subsequently metabolized to the 25-hydroxy derivative (25-OH-D) in the liver by an enzyme system which may or may not be regulated. The subsequent release of 25-OH-D from the liver is not well understood. There is evidence that it is secreted into the bile and subsequently reabsorbed by the intestine. The relative importance of this "enterohepatic" process and the release of this metabolite directly into the circulation from the liver is not known (26). 

Sample Collection and Enzyme Stability. Serum samples are collected with chemically clean, sterile glassware. Blood is allowed to clot at room temperature, the clot is gently separated from the test tube with an applicator stick, and the blood is centrifuged for 10 minutes at 1,000 g. If the red cells are known to contain the enzymes whose activity is being measured, as in the case of LD, even slightly hemolyzed serums must be discarded. When acid phosphatase is to be measured, the serum should be placed immediately in ice and processed as soon as possible, or it should be acidified by the addition of a small amount of sodium citrate. Anticoagulants such as EDTA, fluoride and oxalate inhibit some serum enzymes. However, heparin activates serum lipoprotein lipase. 

Esterbauer et al. (1991) have demonstrated that /3-carotene becomes an effective antioxidant after the depletion of vitamin E. Our studies of LDL isolated from matched rheumatoid serum and synovial fluid demonstrate a depletion of /8-carotene (Section 2.2.2.2). Oncley et al. (1952) stated that the progressive changes in the absorption spectra of LDL were correlated with the autooxidation of constituent fatty acids, the auto-oxidation being the most likely cause of carotenoid degradation. The observation that /3-carotene levels in synovial fluid LDL are lower than those of matched plasma LDL (Section 2.2.2) is interesting in that /3-carotene functions as the most effective antioxidant under conditions of low fOi (Burton and Traber, 1990). As discussed above (Section 2.1.3), the rheumatoid joint is both hypoxic and acidotic. We have also found that the concentration of vitamin E is markedly diminished in synovial fluid from inflamed joints when compared to matched plasma samples (Fairburn etal., 1992). This difference could not be accounted for by the lower concentrations of lipids and lipoproteins within synovial fluid. The low levels of both vitamin E and /3-carotene in rheumatoid synovial fluid are consistent with the consumption of lipid-soluble antioxidants within the arthritic joint due to their role in terminating the process of lipid peroxidation (Fairburn et al., 1992). 

There is very little evidence relating to the role of ROMs in cholestatic liver disease. Serum selenium and glutathione peroxidase activity are decreased in humans with intrahepatic cholestasis of pregnancy (Kauppila et al., 1987). Low levels of vitamin E have been reported in patients with primary biliary cirrhosis, and in children with Alagille s syndrome or biliary atresia (Knight et al., 1986 Jeffrey etal., 1987 Lemonnier etal., 1987 Babin etal., 1988 Kaplan et al., 1988 Sokol etal., 1989). Serum levels of Mn-SOD are increased in patients with all stages of primary biliary cirrhosis compared with patients with other forms of chronic liver disease, although whether this causes or results from the disease process is unclear (Ono etal., 1991). 

In bronchitics, there have been reports of elevated serum-conjugated dienes, hydroperoxides and aldehydes, and a claim of clinical eflicacy as well as normalization of these parameters after vitamin E therapy (Kleiner et al., 1990). However, these patients were given combined therapy including steroids and thus the effect of vitamin E alone cannot be assessed. N-Acetylcysteine administered to chronic bronchitics increased plasma cysteine from a below-normal baseline but it has not been shown that this intervention had any effect on the disease process, the dosing being of short duration, nor were there short-term effects of the release of ROS from blood neutrophils (reviewed by MacNee et al., 1991). A... 

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