Masaka Kawade

Transient changes of serum lipoprotein(a) as an acute phase protein

Serum lipoprotein(a) (Lp(a)) was serially determined after acute attacks of myocardial infarction and after surgical operations. Acute phase proteins, such as C-reactive protein, alpha 1-acid glycoprotein, alpha 1-antitrypsin and haptoglobin, increased rapidly and markedly after the episodes. Initial values of serum Lp(a) concentrations were almost the same in both groups. Increases in serum Lp(a) levels were also observed during the first few days, with a return to the initial levels after more than 1 month. The periods for reaching maximal levels of acute phase proteins were similar in both groups of patients. On the contrary, the period required for Lp(a) to reach the maximal level in the myocardial infarction group was significantly longer than in the post-operative group. The present study suggests that Lp(a) has the characteristics of an acute phase reactant and may play an important role in recovery from tissue damage.

Lipoprotein(a) in nonhuman primates Presence and characteristics of Lp(a) immunoreactive materials using anti-human Lp(a) serum

Lipoprotein(a) (Lp(a] immunoreactive materials were examined in serum samples from 77 nonhuman primates of 24 species by Ouchterlonys double diffusion procedure and an enzyme-linked immunosorbent assay (ELISA) using rabbit antisera to human Lp(a). The precipitates obtained with sera from orang-utan and chimpanzee formed reactions of complete identity with the Lp(a) precipitate with human serum. When sera from Old World monkeys and human subjects were tested in wells next to each other, spurs developed between the 2 precipitates, indicating that Lp(a)-like lipoproteins in Old World monkeys have partial identity with human Lp(a). Lp(a) immunoreactive materials were identified in association with lipids by means of fat staining of the precipitates. On the other hand, reactants which could be precipitated with anti-human Lp(a) sera were not detectable in prosimians and New World monkeys. These results suggest that serum Lp(a)-like lipoprotein is phylogenetically acquired in Old World monkeys. However, the possibility that the structures of serum Lp(a)-like lipoproteins in prosimians and New World monkeys are too different to react with anti-human Lp(a) sera cannot be ruled out.

Determination of serum apo A-IV concentration in patients receiving total parenteral nutrition

SummarySerum apolipoprotein (apo) A-IV levels were determined in patients receiving total parenteral nutrition (TPN) by an immunoassay using a specific antiserum against apo A-IV purified from human sera. The value was significantly lower than that of normal subjects (p<0.001), and the level correlated significantly with the duration of TPN. In a patient receiving TPN, serum apo A-IV concentration decreased during TPN and returned to normal levels after resuming oral intake of diet.This finding indicates that serum apo A-IV is a new parameter for nutritional assessment, since the protein is exclusively synthesized in the gut, being different from other rapid turnover proteins which are mainly synthesized in the liver.

Alterations in erythrocyte membrane lipids in abetalipoproteinemia: phospholipid and fatty acyl composition.

Scanning electron microscopic observation revealed that there were wide variations including typical acanthocytes in morphology of erythrocytes from a patient with abetalipoproteinemia. The erythrocyte membrane phospholipids and cholesterol contents from a patient was higher by 25% compared to an age-matched control subject. Analysis of phospholipid composition of red blood cells showed an increase of sphingomyelin (25.1----30.1%) with a concomitant decrease of lecithin (27.5----21.0%). Thus, the sphingomyelin/lecithin ratio was increased dramatically (0.91----1.43). As for fatty acyl chain composition of main phospholipids, an increased percentage of palmitic acid and docosahexaenoic acid and a decreased proportion of arachidonic acid and lignoceric acid were observed for sphingomyelin. There was an increment of palmitic acid which was accompanied with a decrease of linoleic acid in lecithin. On the other hand, no significant difference was shown in the fatty acid composition of phosphatidylethanolamine and phosphatidylserine plus phosphatidylinositol between a patient and control.

Lipoprotein patterns in hepato-biliary diseases

アガロースゲル電気泳動法を用いて,肝,胆道疾患におけるリボ蛋白像を観察し,各リボ蛋白分画の脂質染色性と移動度の差から9型に分類した.非代償性肝硬変の多くはpre-β帯が消失し,α,β帯の減少したA型を示した.慢性肝炎ではpre-βがβに連続したB型を示した.閉塞性黄疸,急性肝炎で,総ビリルビン,血中胆汁酸の著明な増加のみられた症例はα帯が消失し,幅広いβ帯のみが泳動されるL型を示した. 一般にリボ蛋白泳動後,デンシトメトリーにより得られたα%はアポA濃度と相関が見られたが,幅広く濃染したα帯を示すM型の2例でアポA濃度はむしろ低下していた. 経過を追って観察した急性肝炎症例では症状の改善に伴ってpre-β帯が出現した.又細いβ帯のみ泳動されるA-L型をとった症例は予後不良であった. リポ蛋白像の観察は肝,胆道疾患の診断,予後の判定に有用な指標になると考えられた.