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The effects of hydroxyethyl starch on the final stages of hemostasis were investigated in vivo and in vitro. When compared to control solutions of either 5 percent albumin or isotonic (0.9%) NaCl, 6 percent hydroxyethyl starch (HES) exerted several effects. Results of in vivo studies were as follows: following infusion of 1 liter of 6 percent HES into healthy subjects, fibrinogen and antithrombin-III concentrations fell slightly due to plasma volume expansion and consequent dilution. Concentrations of fibrin monomer and fibrin-fibrinogen degradation products remained unchanged. Thrombin and reptilase clotting times were shortened to indicate rapid detection (and presumably accelerated formation) of fibrin clots. Urokinase-activated clot lysis times were shortened to suggest rapid fibrinolysis. Results of in vitro studies were similar. Shortened thrombin, reptilase, and urokinase-activated clot lysis times were reproduced in vitro by mixing HES, but not albumin or NaCl, with normal plasma. Although these findings qualitatively are similar to those reported previously for dextran, the molecular mechanisms involved and the clinical importance, if any, of the hemostatic effects remain to be defined. Thus, it would be premature to conclude either that HES or dextran exert identical biological effects on hemostasis or that the two agents possess similar clinical properties. HES has an excellent safety record when it has been used during leukocytapheresis and for plasma volume expansion in recommended doses. Its effects when given in larger doses remain to be defined.

A group of 70 adults with end-stage liver disease received 87 homologous liver transplants from 7/11/81 and 7/11/83. The recipients fell into the following diagnostic categories: postnecrotic cirrhosis (PNC) in 22, primary biliary cirrhosis (PBC) in 18, cancer or neoplasia (CA) in 11, sclerosing cholangitis (SC) in 8 and miscellaneous (MISC) in 11. Survival for six months or longer was 46%: survival by group was PBC = 67%, CA = 55%, PNC = 45%, SC = 25%, and MISC = 18%. Preoperative coagulation profiles were evaluated on 64 of the 70 first transplant patients by assigning a score derived from one point per abnormality in each of 8 tests. Mean coagulation abnormality scores (CAS) were strikingly elevated in the PNC and MISC groups. Mean intraoperative blood product usage was 43 units of RBCs, 40 units of fresh frozen plasma (FFP), 21 units of platelets, and 9 bags of cryoprecipitate. Direct correlations were found between CAS and RBC usage (+0.454, P = less than .001), CAS, and survival of 6 months or longer (-0.281, P = less than .02), and RBC usage and survival (-0.408, P = less than .001). These findings indicate that the degree of coagulation abnormality and the type of liver disease may be predictive of intraoperative blood usage and survival in liver transplantation in adults.

Subnormal activity of hepatic uroporphyrinogen decarboxylase is responsible for the derangement of porphyrin biosynthesis in both sporadic and familial porphyria cutanea tarda, but the enzymatic defect is not clinically expressed in the absence of hepatic siderosis. The pedigree study described here offers support for the hypothesis that a single allele for HLA-linked hereditary hemochromatosis is responsible for the hepatic siderosis in sporadic porphyria cutanea tarda. A two-locus causation model for sporadic porphyria cutanea tarda might explain both the observed incidence of overt cases and the rarity of multiple affected individuals within a pedigree.

A 2.5-kb cDNA clone for human p53 tumor antigen has been isolated. This clone contains the entire coding region including 135 bp upstream of the first ATG. Comparison of the nucleotide sequence of human p53 and mouse p53 demonstrates that the first ATG in human p53 corresponds to the second ATG (codon No. 4) in mouse p53. The human p53 comprises 393 residues and is longer than the mouse p53 due to six additional codons present at the region corresponding to exon 4 of the mouse p53 gene. The DNA sequence homology between the coding regions of mouse and human p53 is 81% and the conservation of homology is not equally distributed along the molecule. When inserted into SV40-based expression vectors the human p53 cDNA successfully directs the production of a polypeptide with an apparent mol. wt. of 55 kd which can be precipitated by monoclonal antibodies to p53.