A BSTRA CT Vitamin A circulates in human plasma as retinol bound to a specific transport protein. This protein differs from the known low and high density plasma lipoproteins and has a hydrated density greater than 1.21. In order to study this protein, volunteers were injected intravenously with retinol-15-14C. Plasma was collected 1-3 days later, and the purification of retinol-binding protein (RBP) was monitored by assaying for 14C and also by following the fluorescence of the proteinbound retinol. Purification of RBP was effected by the sequence: Cohn fractionation, chromatography on columns of Sephadex G-200 and diethylaminoethyl (DEAE)-Sephadex, preparative polyacrylamide gel electrophoresis, and finally chromatography on Sephadex G-100. These procedures resulted in a preparation of RBP which was at least 98%o pure and which had been purified more than 1500-fold. Purified RBP has al mobility on electrophoresis and has a molecular weight of approximately 21,000-22,000. There appears to be one binding site for retinol per molecule of RBP.
Summary CA19-9, a serum marker for pancreatic cancer, gives false-negative results in patients who are negative for the Lewis blood group phenotype. To determine whether other markers may compensate for this drawback, serum levels of CA50, Span-l, sialyl SSEA-1 and Dupan-2 were assayed and compared with those of CA19-9 in 207 normal subjects and in 200 patients with pancreatic carcinoma whose Lewis blood group phenotypes were confirmed. In normal subjects with the Lewis negative phenotype, the serum levels of CA50 and Span-i, as well as CA19-9, were significantly low, whereas those of sialyl SSEA-1 were independent of the Lewis blood group phenotype. Serum levels of Dupan-2 were significantly higher in normal subjects with the Le (a -b -) phenotype as compared with those with Le(a -b +). The sensitivity for pancreatic carcinoma was 81% for CA19-9, 84% for CA50, 82% for Span-i, 51% for sialyl SSEA-1 and 63% for Dupan-2. Among the 39 CA19-9 negative patients, 13 were determined as being Lewis negative by the serum dot-ELISA technique. Although the positive rates were essentially comparable when each marker was combined with CAl9-9, a highly elevated serum level of Dupan-2, which strongly suggested the presence of malignancy, was most frequently encountered in 39 patients who were not diagnosed by CA19-9 assay, especially those with Lewis negative blood groups. With regard to the three other markers, we found few patients with a highly elevated serum level in either the Lewis-negative or -positive groups. We conclude that Dupan-2 tended to be elevated in patients with pancreatic cancer who were negative for the Lewis blood group phenotype.
In 16 untreated patients with hyperthyroidism due to Graves' disease, serum antidouble stranded DNA antibody, measured by RIA, was positive (greater than 20 U/ml) in 14. In methimazole-treated patients with T3-suppressible thyroid uptake, anti-DNA antibody was found in 9% (3 of 35). The frequency of positive tests in methimazole-treated patients with T3-nonsuppressible thyroid uptake and in surgically treated patients was 24% (5 of 21) and 57% (4 of 7), respectively. Among anti-DNA antibody-negative (less than 9 U/ml) and weakly positive (10-19 U/ml) patients, those with T3-suppressible thyroid uptake had lower anti-DNA antibody titers than those with T3-nonsuppressible thyroid uptake. Among 32 patients with Hashimoto's thyroiditis, anti-DNA antibody was positive in 7. None of the patients with simple goiter had positive or weakly positive anti-DNA antibody results. Although the quantity of antibodies did not correlate well in individual patients, the rates of positive TSH binding-inhibiting immunoglobulin and anti-DNA antibody tests were roughly comparable in these patient groups. None of these patients with thyroid disease associated with anti-DNA antibody had clinical or other serological evidence suggestive of systemic lupus erythematosus or related collagen vascular disorders. The finding of anti-DNA antibody provides a new aspect of immunological abnormality associated with hyperthyroidism of Graves' disease.
1. The urinary excretion of a metabolite of illudin S after oral administration to rat has been studied. 2. From an ethyl acetate extract of urine, metabolite 1, a cyclopropane ring-cleavage compound, was identified by liquid chromatographic-mass spectrometric analysis 3. A hplc method for determination of the metabolite in rat urine was developed with extraction using Sep-Pak C18 cartridge followed by liquid-liquid extraction. 4. The metabolite excreted during 3 days after administration of illudin S to rat amounted to approximately 10-19% of the dose as free form and 3-5% of the dose as glucuronide.
The clinical diagnostic utility of CA-50 (time-resolved fluoroimmunoassay) and Span-1 was compared with that of CA19-9 by measuring their levels in sera from patients with pancreatic cancer and other diseases. In pancreatic cancer CA-50, Span-1, and CA19-9 showed similar positive rates (84%, 82%, and 81%, respectively). With regard to the ability to distinguish pancreatic cancer from chronic pancreatitis, however, the specificity of CA-50 and Span-1 was higher than that of CA19-9 (85%, 85%, and 79%, respectively). Despite the similar positive rates of CA-50 and Span-1 in pancreatic cancer, the correlation between these two markers was low. Thus, used in combination, they compensated for each other in the diagnosis of pancreatic cancer. In chronic liver diseases, serum levels of both CA-50 and Span-1 were correlated with that of biliary tract enzymes, alkaline phosphatase, and r-glutamyl transpeptidase. And these two markers were more affected by the biliary system than CA19-9, resulting in the significantly higher positive rates. In these diseases immunohistochemical study showed that all three markers were localized in the epithelial cells of the bile duct, with CA-50 and Span-1 showing a similar tissue distribution.
We have previously described the purification and partial characterization of a new pancreatic cancer-associated antigen, a pancreatic cancer-associated mucin expressing CA19-9, CA50, Span-1, sialyl SSEA-1, and Dupan-2. This study describes the clinical evaluation of various assay systems for this antigen which depend on measuring respective serum levels. Elevated levels of antigen were detected in the sera from both patients with malignant and non-malignant diseases. However, elevated serum levels of CA19-9 and Lewisa and Lewisb epitopes on moieties were restricted to pancreatic and biliary tract cancers, although adequate sensitivity was not attained. Coordinate evaluation of these three markers improved the sensitivity to some extent without loss of specificity for the diagnosis of pancreatic and biliary tract cancers, because of the heterogeneity of the coexpression of these epitopes. We developed additional assay systems with a combination of this antigen and two lectins (Bauhinia purpurea (BPA) and Vicia villosa (VVA)). Elevated levels of BPA- and VVA-reactive antigens were detected in 41% and 31%, respectively, of pancreatic cancer sera samples. Few patients with chronic pancreatitis had an elevated serum level of either antigen, and higher elevated levels of these markers were restricted to the sera of patients with malignancies. Our results suggest that this antigen is found in the sera of patients with various conditions and in the sera of normal subjects but that antigens bearing CA19-9 or Lewisa or Lewisb epitopes and an altered carbohydrate structure recognized by BPA and VVA lectins are preferentially present in the sera of patients with pancreatic and other malignancies.
A new antigen associated with pancreatic cancer was prepared by immunoaffinity chromatography using Fab'-Sepharose beads. This antigen was a glycoprotein of large molecular weight (Mr greater than 8,000,000) in its native state, estimated by size exclusion chromatography on Sephacryl S400. After sodium dodecyl sulfate-polyacrylamide gel electrophoresis and blotting analysis, several cancer-associated glycoconjugates, including CA19-9, CA50, Span-1, Dupan-2, and sialyl SSEA-1, were detected on the antigenic moiety of Mr 90,000. By an enzyme immunoassay for the antigen, elevated levels were found in pooled sera obtained from patients with various malignant and non-malignant diseases and normal subjects. However, the enhanced expression of CA19-9, Lewisa, or Lewisb epitope on the antigen molecule was restricted to the pooled sera from patients with pancreatic cancer. Furthermore, antigens from pancreatic or gastric cancer expressed ligands with intense and specific reactivity for Bauhinia purpurea (BPA), peanut (PNA), and Vicia villosa (VVA) lectins. The present assay system of the antigen, using both monoclonal antibodies (CA19-9, Lewisa, and Lewisb) and lectins (BPA, VVA and PNA), will provide a useful approach to the diagnosis of pancreatic cancer.
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