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Eosinophils are found in the blood and tissues of patients with allergic diseases such as asthma, allergic rhinitis and also atopic dermatitis. The number of eosinophils in the diseased tissue generally correlates with the expression of clinical symptoms. Originally, the eosinophil was regarded as having an exclusively protective role, for example in host defense against parasites. More recently, the eosinophil is recognized as being a pro-inflammatory cell that can mediate allergic disease. The eosinophil is active in inflammation through the release of granule proteins and the synthesis and release of inflammatory mediators. The important eosinophil granule proteins are major basic protein (MBP), eosinophil cationic protein (ECP), eosinophil derived neurotoxin (EDN) and eosinophil peroxidase (EPO). These proteins have toxic effects on the surrounding tissue. Of additional importance for the allergic inflammatory reactions are membrane-derived mediators such as leukotriene C4 (LTC4), platelet activating factor (PAF) and Charcot-Leyden crystals. These mediators are synthesized and released after eosinophil activation, and act toxic on surrounding cells. Eosinophils are active in asthma, and increased numbers and eosinophil-derived mediator concentrations have been documented in bronchial biopsies, BAL and sputum. In addition, eosinophil granule proteins and inflammatory mediators are found in nasal secretions in allergic rhinitis. In atopic dermatitis one finds activated eosinophils and depositions of eosinophil granule proteins in skin biopsies. Eosinophils are not only active in mediating allergic inflammation, but interact in cellular networks with antigen presenting cells (APC), mast cells, and T lymphocytes. These other cells influence eosinophil maturation, mobilization, tissue localization and activation.

Cells obtained by continuous perfusion with collagenase maintained their ultrastructure and their capacity for protein synthesis in contrast to mechanically isolated rat liver cells. Albumin and angiotensinogen (renin substrate) are synthesized and secreted and the synthesis of both proteins is stimulated by addition of hydrocortisone. As cell suspensions allow the simultaneous investigation of several samples under well defined conditions they can serve as an excellent model for the study of regulatory mechanisms of serum protein synthesis.

The studies were carried out with pigs and rats. The radioactive animo acids (14C leucine and 3H lysine) were administered to the pigs by way of a catheter tube into the jugular vein. Subsequently, the time pattern of the distribution of the specific amino acid radioactivity was followed in the TCE soluble and Tce precipitable fractions of the blood plasma (TCE= trichloro-acetic acid). The radioactive labelling in rats was carried out by injecting 14C leucine into the portal vein. The animals were killed after incorporation periods from 2 to 60 mins, and the levels of specific radioactivity were estimated in the TCE soluble and TCE precipitable fractions of the blood plasma, in the liver and in the skeletal muscles. The experimental results clearly indicated that the specific radioactivity of the tracer amino acids and the rate of incorporation of radioactivity into tissue proteins were greatly influenced by the size of the free amino acid pool within the range of distribution of the tracer. An estimation of the magnitude of the pool of free amino acids within the distribution range of the tracer can be obtained from the curve pattern for the decline of specific radioactivity of the corresponding free amino acid in the blood plasma. This pool exhibits a high rate of turnover. In all studies made to evaluate in vivo processes of protein synthesis by use of radioactive tracer amino acids it will be particularly important that consideration should be given to the specific radioactivity of the amino acid in the precursor pool for protein synthesis.

Transcobalamin II (TC II) is a serum protein responsible for transporting vitamin B12 to the cells. A previous observation of a child with congenital TC II deficiency and agammaglobulinemia suggested that this protein plays an important role in the immune response. Accordingly, TC II levels ere determined in 32 patients with autoimmune disease (AID) (i.e. 26 with lupus erythematosus, 4 with dermatomyositis, and 2 with autoimmune hemolytic anemia) and in 40 patients with acquired immunodeficiency due to chemotherapy. It was found that elevated TC II levels corresponded to active phases of AID. Changes in TC II levels correlated better with the clinical course of AID than complement, antinuclear antibody or native DNA binding capacity. This suggests that TC II could be a valuable parameter in following up activity of AID.

In a randomised study the influence of 3 different amino acids (AA) solutions on nitrogen balance, plasma protein synthesis, and plasma and urine AA pattern was investigated in postoperative (p.o.) cancer patients. The patients in group I received a balanced AA solution designed especially for p.o. patients with 10 percent branched chain amino acids (BCAA), those in group II a solution with 60 percent BCAA and those in group III a solution with 67 percent alanine. All patients received the same amount of nitrogen (0.16 g/kg BW/day) and energy (2.p.o. day: 80 kJ/kg BW/day; 3.-5. p.o. day: 160 kJ/kg BW/day) with a 3:1 ratio of carbohydrate to fat calories. No difference was observed between the three groups for mean daily nitrogen balances, however, the cumulative nitrogen balance of group I (-4.5 +/- 3.6 g) was significantly (p less than 0.05) improved compared to group II (-12.2 +/- 4.2 g). The p.o. decreased concentrations of short-life plasma proteins (prealbumin, transferrin, retinol-binding protein) increased until the end of the study period without any statistic differences between the three groups. On the 2nd p.o. day especially the gluconeogenetic AA were decreased in all patients, but were nearly normal in all patients on the 5th p.o. day. In conclusion the increased administration of BCAA neither improved nitrogen retention nor plasma protein synthesis and does not seem advantageous in the postoperative total parenteral nutrition.