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To identify factors contributing to the pathogenesis of autoimmune chronic active hepatitis (CAH) healthy relatives of 13 patients with the disorder were followed prospectively for 4 years. 58 relatives were monitored for various serological markers and for T-lymphocyte migration inhibitory activity every 2 months. 3 cases of subclinical acute hepatitis A occurred during the study. In 2 of the 3 subjects, before hepatitis A virus (HAV) infection, there was a defect in suppressor-inducer T lymphocytes specifically controlling immune responses to the asialoglycoprotein receptor, an antigen expressed on the hepatocyte surface. In these 2 subjects, specific helper T cells and antibodies to the asialoglycoprotein receptor persisted and increased after acute hepatitis A, and autoimmune CAH type 1 developed within 5 months. Thus, in susceptible individuals HAV is a trigger for autoimmune CAH.

Cell adhesion molecules (CAMs) of the immunoglobulin supergene family may play important roles in tumorigenesis and the development of metastatic disease. In a variety of human malignancies, tumor progression has been observed to be associated with changes in CAM expression. An early event in colorectal tumorigenesis appears to be the down regulation of a normally expressed CAM, DCC. Over-expression of a second CAM, carcinoembryonic antigen, is associated with colorectal tumors which have a high risk for metastasis development. Several tumors, including Wilms tumors and neuroblastoma, have been found to express a developmentally regulated form of NCAM which inhibits a variety of cell-cell interactions. Malignant cells not only show aberrations in the expression of their CAMS and thus their normal cell-cell interactions, but establish new adhesive interactions. The development of metastatic potential in cutaneous melanoma is associated with the de novo expression of two CAMs, one of which is ICAM-1, a molecule mediating adhesion between the tumor cells and leukocytes.

Progesterone receptors (PgR), estrogen receptors (ER), and androgen receptors (AR) were assayed consecutively for hepatocellular carcinoma (HCC) that was surgically removed from 19 men and three women. The methods of receptor assay were the enzyme immunoassay (EIA) for PgR and the dextran-coated charcoal (DCC) technique for ER and AR. The patients ranged in age from 32 to 77 years (average, 60.3 years). No patients had received any specific anti-cancer therapy before tissue collection. All patients but one had underlying liver disease: cirrhosis in 13 and chronic hepatitis in eight. The positive rate of each receptor was 18% for PgR, 48% for ER, and 82% for AR. The titer was highest for AR, intermediate for ER, and lowest for PgR. The titers of PgR in four PgR-positive patients ranged from only 1.1 to 3.0 fmol/mg of protein. There was no relationship between PgR, ER, and AR in terms of positivity and titer. Also, other clinical and histopathologic data did not influence the positivity or concentration of these three sex hormone receptors. It can be concluded that no or little PgR exists in the cytosol of untreated HCC.

Polyomavirus (Py) DNA replication is regulated by its enhancer, which contains an AP1 site, c-Jun and c-Fos, the products of nuclear protooncogenes c-jun and c-fos, form the heterodimeric transcriptional activating factor AP1. Overexpression of c-fos and c-jun genes strongly stimulated Py DNA replication from the Py origin of replication as well as transcription from the Py early promoter through the AP1 binding site. The cAMP response element (CRE)-binding protein CREB stimulated only transcription, not DNA replication, through the CRE under similar conditions. The results indicate that AP1 functions as a regulator of DNA replication and that the mechanism of activation of Py DNA replication by AP1 is distinct from that of activation of transcription from the Py early promoter.

Biopsy specimens of small breast carcinomas are often insufficient for both diagnosis and the biochemical determination of estrogen receptor (ER) protein. Recent reports from various laboratories have shown the utility of immunohistochemical detection of ER protein in paraffin-embedded tissue sections. We used immunohistochemical (IHC) staining with the Abbott ER antibody (H222) and in situ hybridization (ISH) analysis with a 35S-labeled and a biotinylated oligonucleotide probe to detect ER protein and messenger RNA (mRNA) in tissue sections of 53 breast carcinomas. The dextran-coated charcoal (DCC) assay of these same cases revealed positive receptor levels in 31 of 53 cases, whereas the IHC method was positive in 33 of 53 cases. ISH for detection of ER mRNA was more sensitive than IHC or the biochemical assay for estrogen binding proteins, as the isotopic probe detected ER mRNA in 47 of 53 cases, whereas the biotinylated probe detected ER mRNA in 46 of 53 cases. These results indicate that ER protein can be readily detected in enzyme-treated paraffin tissue sections and that the IHC detection of ER protein correlates highly with the DCC assay. ISH with isotopic and biotinylated probes detects ER mRNA in most cases found to be positive for ER protein and also in many cases without detectable ER protein. Although detection of ER protein in paraffin sections correlates highly with the biochemical assay in this report and in other reported studies, the clinical significance of increased sensitivity by ISH is unknown and must await clinical correlative follow-up studies.

The preceding discussions outline the various forms of cirrhosis that may be encountered in the elderly population. Cirrhosis is not uncommon in older patients. Although it has been stated that most cirrhosis in the elderly is due to alcohol, these assumptions are perhaps overestimations. In the authors' experience, many older patients are inappropriately labeled with alcoholic liver disease--presumed guilty until proven otherwise--and have subsequently been shown to have nonalcoholic liver disease. Careful investigation is required. Hepatotoxic drug exposure (e.g., to alpha methyldopa, nitrofurantoin, or isoniazid) should be ruled out, and hepatitis B and hepatitis C serology obtained. Primary biliary cirrhosis may occur in both sexes, and thus antimitochondrial antibody should be assayed. Severe heart disease may result in cardiac cirrhosis in the elderly, with ascites and hepatomegaly. Alpha 1-antitrypsin deficiency, primary sclerosing cholangitis, idiopathic hemochromatosis, and chronic autoimmune hepatitis may result in advanced cirrhosis in the elderly; appropriate serum studies should be obtained. If questions remain and if therapy may be changed, liver biopsy can be performed. A recent study suggested, however, that the risk of hemorrhage from liver biopsy in the elderly may be increased, especially if malignancy is present. The era of treatment for liver diseases has arrived. Colchicine, methotrexate, ursodeoxycholic acid, and others have shown promise in the treatment of PBC, primary sclerosing cholangitis, and alcoholic liver disease. Corticosteroids may be lifesaving in autoimmune liver disease. Phlebotomy remains the treatment of choice for hemochromatosis in any age group. Interferons and other antiviral agents are being used in chronic type B and type C hepatitis. Treatment of the complications of cirrhosis in the elderly may be safely accomplished. Advanced age is not a contraindication to variceal sclerotherapy. Vasopressin, however, may be contraindicated in the elderly patient if there is an underlying history of atherosclerotic coronary or peripheral vascular disease. Large-volume paracentesis and peritoneal venous shunting can afford symptomatic relief of ascites, even in the geriatric population. Finally, as noted previously, advanced age is no longer to be considered an absolute contraindication for liver transplantation. The evaluation of liver disease in the elderly may be diagnostically challenging, and its treatment rewarding.

Antithrombin-III (AT-III) activity was measured at the time of admission in 46 horses referred with colic. Differences in AT-III activities between animals treated medically or surgically and survivors or non-survivors were compared. The mean AT-III values for the horses treated medically (76.2 per cent), surgical survivors (69.5 per cent) and surgical non-survivors (55.9 per cent) were significantly different from the reference value for healthy adults (92 to 108 per cent). The mean AT-III activity of the survivors was significantly (P less than 0.01) greater than that of the nonsurvivors. The majority of the survivors (11 to 13 horses) had AT-III activities exceeding 60 per cent of normal, whereas that of 10 of the 14 non-survivors was less than 60 per cent of normal. There was an apparent distinction between the survivors and non-survivors at approximately 60 per cent of normal AT-III activity.

The Bacillus subtilis spoIIIG gene codes for a sigma factor termed sigma G which directs transcription of genes expressed only in the forespore compartment of the sporulating cell. Use of spoIIIG-lacZ transcriptional fusions showed that spoIIIG is cotranscribed with the spoIIG operon beginning at t0.5-1 of sporulation. However, this large mRNA produced little if any sigma G, and transferring the spoIIIG gene without the spoIIG promoter into the amyE locus resulted in a Spo+ phenotype. Significant translation of spoIIIG began at t2.5-3 with use of an mRNA whose 5' end is just upstream of the spoIIIG coding sequence. Synthesis of this spoIIIG-specific mRNA was not abolished by a deletion in spoIIIG itself. Similar results were obtained when a spoIIIG-lacZ translational fusion lacking the spoIIG promoter was integrated at the amyE locus. These data suggest that synthesis of sigma G is dependent neither on transcription from the spoIIG promoter nor on sigma G itself but can be due to another transcription factor. This transcription factor may be sigma F, the product of the spoIIAC locus, since a spoIIAC mutation blocked spoIIIG expression, and sequences upstream of the 5' end of the spoIIIG-specific mRNA agree well with the recognition sequence for sigma F. RNA polymerase containing sigma F (E sigma F) initiated transcription in vitro on a spoIIIG template at the 5' end found in vivo, as did E sigma G. However, E sigma F showed a greater than 20-fold preference for spoIIIG over a known sigma G-dependent gene compared with the activity of E sigma G.

The properties of two isoforms, alpha and beta, of rabbit antithrombin III (ATIII) were compared in the presence of undamaged or de-endothelialized rabbit aortic wall. Similar quantities of ATIII-alpha and ATIII-beta bound to and rapidly saturated the endothelium in vitro, but the rate of transendothelial passage of ATIII-beta exceeded that of ATIII-alpha by 22%. Furthermore, ATIII-beta was adsorbed approximately twice as rapidly as ATIII-alpha by the subendothelium of the de-endothelialized aorta. Binding of both isoforms was decreased (ATIII-beta more than ATIII-alpha) by pretreating the subendothelial surface with heparitinase. Also, subendothelium-bound ATIII-beta was desorbed more readily than bound ATIII-alpha by thrombin. In vivo, the rate of uptake of iodine-131-labeled ATIII-beta from the circulation by the aortic wall and the major organs was 30-50% faster than that of iodine-125-labeled ATIII-alpha. In contrast, the uptake of 131I-ATIII-beta by the de-endothelialized aorta in vivo was three times faster than that of 125I-ATIII-alpha. By these criteria, ATIII-beta is the more active of the two isoforms. We surmise that plasma and, consequently, vessel wall levels of ATIII-beta may be vital for controlling thrombogenic events caused by injury to the vascular wall.

Antithrombin-III-Hamilton has been shown to be a structural variant of antithrombin-III (AT-III) with normal heparin affinity but impaired protease inhibitory activity. The molecular defect of AT-III-Hamilton is the substitution of Thr for Ala at amino acid residue 382. The plasma of affected individuals contains approximately equal quantities of normal AT-III and AT-III-Hamilton. When AT-III was isolated from the plasma of the propositus by heparin-Sepharose chromatography, it had identical mobility on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) to normal plasma-derived AT-III, under both reducing and nonreducing conditions. However, the AT-III-Hamilton species, separated from the propositus' normal AT-III by a combination of heparin-Sepharose and thrombin-Sepharose chromatography, had increased mobility on reductive SDS-PAGE compared with AT-III from the propositus isolated by heparin-Sepharose chromatography alone. Under nonreducing conditions this AT-III-Hamilton species had decreased mobility compared with AT-III from the propositus (or normal AT-III) isolated only by heparin-Sepharose chromatography. When incubated with either human alpha-thrombin or human factor Xa, this AT-III-Hamilton species was unreactive. Approximately 50% of the AT-III from the propositus isolated by heparin-Sepharose chromatography, when incubated with either human alpha-thrombin or factor Xa, did not form complex but was cleaved, presumably at the reactive center Arg393-Ser394. To further substantiate the biological behavior of this variant, AT-III-Hamilton polypeptides were synthesized in a cell-free system. This recombinantly produced AT-III-Hamilton, when incubated with either human alpha-thrombin or factor Xa, was cleaved by both these proteases, but did not show any complex formation. The results indicate that AT-III-Hamilton does not form a stable covalent inhibitory complex with these serine proteases but can be cleaved at the reactive center. Thus, the inhibition of serine proteases by their natural inhibitors (the serpins) involves at least two separate, but interrelated events; hydrolysis at the reactive center followed by complex formation. AT-III-Hamilton is capable of only the first of these events.

On the basis of a review of the literature and five case histories, the pathophysiological and clinical features in pregnant women with haemolysis, elevated liver enzymes and thrombocytopenia which together constitute the HELLP syndrome (haemolysis, elevated liver enzymes and low platelet count) are illustrated. This syndrome describes a complicated obstetric course with greatly increased neonatal and maternal morbidities. Hypertension/proteinuria are common but are not obligatory. The condition should be suspected in pregnant women with pain under the right rib margin and unexplained jaundice. The diagnosis is verified by the blood picture, liver enzyme count and a blood smear. Women with verified HELLP syndrome and gestational age greater than 34 weeks should be delivered immediately. Women with the same syndrome and gestational age less than 32 weeks should be delivered if the condition cannot be rapidly controlled. In exceptional cases cesarean section may be necessary. On the basis of the coagulation status, the defective plasma components may be supplied (e.g. fresh frozen plasma and antithrombin-III). Plasmapheresis and specific pharmacological intervention must be considered as experimental at present, although these present promising therapeutic possibilities.

Hemochromatosis has been reported in several patients with chronic hemolytic anemia due to pyruvate kinase deficiency. We describe here a further patient with such an association and review the literature on the subject. We hypothesize that iron overload may occur in patients with pyruvate kinase deficiency who are also carriers of the hereditary hemochromatosis gene.

We examined 1,053 blood samples from 48 donors, for the effect of gradual reduction of citrate. We observed that: 1--Platelet count does not show any significant variation between 1/8 to 1/18 ratio. 2--In 13.3% of the cases, platelet clumping starts at 1/18 ratio. 3--There was no significant variation of the thrombin plasma level between 1/8 to 1/16 ratio (by measuring thrombin/ATIII complex). Our results show clearly that we can reduce the citrate ratio to 1/14 without expecting any adverse effect. Therefore we designated 1/14 as the security ratio. Parallel to this we also found that the average level +/- SD of ionized calcium is 100 +/- 10 muMol at 1/14 ratio.

The immunohistochemical estrogen receptor (ER) assay quantitated by image analysis was compared with the biochemical dextran-coated charcoal (DCC) assay in 97 primary breast carcinomas. Frozen sections immunostained for ER with a monoclonal antibody (ER-ICA; Abbott Laboratories, Chicago, IL) and the peroxidase-antiperoxidase technique were scored semiquantitatively by microscopy (HSCORE) and quantitatively [percentage of nuclear area immunopositivity (PNA)] using the CAS 200 image analyzer (Elmhurst, IL). There was a significant and identical correlation between DCC and both HSCORE and PNA. According to sensitivity/specificity calculations, the cut-off points of 10 for HSCORE and 1% for PNA were chosen with positive and negative predictive values of 97.7% and 74.5%, respectively. Low DCC-positive cases between 10 and 50 fmol of ER/mg of protein were immunohistochemically ER positive only in 61.5%. Immunohistochemical results of greater than 150 HSCORE and greater than 15% PNA corresponded to high DCC results of greater than 150 fmol/mg of protein. Immunohistochemical assay quantitated by image analyzer (PNA) is a comparable alternative to biochemical ER, especially when insufficient fresh tissue is available.

In patients with Behçet's disease, venous thrombosis has often been described as a complication. The pathogenesis of this complication, however, has not been fully understood. In this work, various parameters of blood coagulation and fibrinolysis were studied in 20 patients with Behçet's disease and 13 sex-matched healthy volunteers. Patients were classified into three subgroups according to the number of clinical signs involved; group I (no sign): 4 patients; group II (one or two signs): 11 patients; group III (more than three signs): 5 patients. Patients with Behçet's disease, showed an activation of blood coagulation, such as the shortening of prothrombin time (p less than 0.001), decreases in concentrations and activities of plasma antithrombin III (AT-III) (p less than 0.01) and elevated levels of plasma thrombin-antithrombin-III complex (TAT) (p less than 0.01), compared to the control group. Plasma levels (p less than 0.01) and activities (p less than 0.01) of protein C (PC) and total protein S (PS) levels (p less than 0.05) were increased in the patients. Decreased levels of alpha 2-plasmin inhibitor (p less than 0.001) also indicated an activation of fibrinolysis in the patients. When analyzed among the subgroups, patients belong to group II and III showed higher levels of plasma FDP D-dimer (p less than 0.05) and lower levels of plasminogen (p less than 0.05), as compared with patients in group I or control group.(ABSTRACT TRUNCATED AT 250 WORDS)