[The significance of the kallikrein-kinin system in the pathogenesis of essential hypertension]

The levels of plasma kininase II (ACE), a high molecular weight-kininogen (HMW), alpha 2-mega-globular protein (alpha 2M), prekallikrein (PK), alpha 1-antitrypsin (alpha 1 AT) were determined in essential hypertension and control groups. The results showed that there is significant increase of ACE and PK activity and HMW content in patients with essential hypertension than in control group (P less than 0.001). No changes in alpha 2M and alpha 1AT were found. These results suggest that human plasma kallikrein system was inhibited in patients with essential hypertension.

Changes of glycoconjugates in human hepatocellular carcinoma

Receptors of 12 lectins in 25 cases of human hepatocellular carcinomas (HCC) were histochemically investigated by avidin-biotin-peroxidase complex (ABC) method. Liver tissues of five cirrhotic patients and five normal subjects were used as controls. SJA receptor was absent both in HCC and controls, while LCA and PSA receptors were present in all tissues studied here. Receptors of DBA, PHA, PNA, UEAI and SBA which did not bind to normal, cirrhotic and pericarcinomatous liver tissues had the positive rates of 4%, 44%, 16%, 4% and 12% in HCC, respectively. Four lectins which strongly bound to the non-cancer liver tissues had their receptors in 96% (ConA, WGA, RCAI) and 36% (BSAI) of HCC. The pretreatment of tissue sections with neuraminidase abolished most of WGA receptors and exposed some PNA binding sites. There were many differences in lectin distribution between HCC and noncancer liver tissues. The changes of glycoconjugates in HCC were discussed.

Expression of glycoconjugates in intrahepatic cholangiocellular carcinoma

Twenty cases of intrahepatic cholangiocellular carcinoma (IHCCC) were studied by lectin histochemistry for their glycoconjugate expression. Combined alcian blue-peroxidic acid Schiff (ABPS) staining was also made for mucins in these tissues. Results showed that epithelial cells of intrahepatic bile ducts contained varied quantity of DBA, WGA, LCA, Con A, PHA, RCAI, BLAI, SJA, SBA, PSA and UEAI receptors but no PNA receptors. Lectin receptors were present at varying rates; 100% (Con A), 95% (PSA), 90% (LCA), 95% (WGA), 30% (BSAI), 35% (DBA), 65% (PHA), 74% (PNA), 85% (RCAI), 35% (SBA), 25% (SJA) and 55% (UEAI), respectively. The positive rates in well-differentiated IHCCC were significantly higher than those in either moderately or poorly-differentiated IHCCC. The distribution of lectin receptors in IHCCC was obviously different from that in peri-carcinomatous, cirrhotic and normal liver, and also differed from that in epithelial cells of normal intrahepatic bile ducts. All larger ducts were stained by ABPS and were mainly blue colour, while only 80% of IHCCC were positive for ABPS staining. Most of them were blue, others were red or purple. The results suggest that the expression of glycoconjugates had changed after the neoplastic transformation of bile duct cells.

A simplified method for the preparation of WGA-Sepharose 4B and its use in the purification of MN blood group antigens

A simplified method for the preparation of wheat germ agglutinin(WGA)-Sepharose 4B by coupling highly purified WGA, prepared by improved affinity chromatography, with BrCN activated Sepharose 4B in a solution of high carbonate buffer is described. The amount of WGA linked to Sepharose 4B was 82.40% (3.07 mg WGA per ml Sepharose 4B). MN blood group antigens of human erythrocyte membranes purified with WGA-Sepharose 4B affinity chromatography showed a single band on sodium dodecyl sulfate/polyacrylamide gel electrophoresis (SDS/PAGE). The yield of the antigens from 400 mL fresh blood was 32-40 mg. The WGA-Sepharose 4B column could be used several times without loss of activity.

Arginine, protein malnutrition, and cancer

The amino acid arginine has anabolic and immunostimulatory properties. This study evaluated the potency of arginine in limiting the severe nutritional and immunological insults of protein calorie malnutrition and increasing tumor load. In protein-depleted A/J mice (n = 340) bearing either an immunogenic (C1300) or poorly immunogenic (TBJ) neuroblastoma, arginine supplementation [1%] significantly augmented T lymphocyte responses (mitogenesis, interleukin-2 production) compared with both a glycine-supplemented and nonsupplemented group. Arginine supplementation significantly retarded the growth of C1300 and prolonged median host survival. These results correlated with augmented autologous mixed lymphocyte tumor cell responses and enhanced specific cytotoxicity. This anti-tumor effect was not demonstrated in mice bearing TBJ where both arginine and glycine stimulated tumor growth compared with nonsupplemented mice. There was no significant difference between arginine and glycine in preservation of carcass weight. These studies suggest that the immunostimulatory effects of arginine are not due to supplemental nitrogen and that an associated antitumor effect is dependent on tumor antigenicity.