Angelo Burlina

Troponin T as a marker of ischemic myocardial injury.

A study was undertaken to evaluate the clinical relevance of serum troponin T (TnT) as a marker of ischemic myocardial injury, using a new automated enzyme immunoassay. The reference range for serum TnT was established by measuring serum TnT concentrations in blood obtained from 262 healthy subjects. The serum concentration of TnT was compared to serum creatine kinase activity, creatine kinase MB (mass and activity), myoglobin concentration, and lactate dehydrogenase activity: in 77 patients with myocardial infarction (55 received thrombolytic treatment); in 32 patients with unstable angina; in 30 patients with nonischemic heart diseases; and in 40 patients with skeletal muscle injuries. Our findings showed that: a) 99% of healthy blood donors had TnT concentrations < 0.10 micrograms/L; b) the test had a high clinical efficiency in the diagnosis of acute myocardial infarction, with a sensitivity of 1.0 and a specificity of 0.88 at a decision level of 0.20 micrograms/L; c) serum TnT had a later peak value (8-38 h), but a wider diagnostic window (> 126 h) than the traditional markers considered in the study; d) serum TnT had an excellent sensitivity in the detection of microinfarctions in patients with unstable angina pectoris; e) the release patterns of serum TnT were qualitatively different in perfused versus nonperfused patients. Peak serum TnT values and time to peak values were statistically different (p = 0.0336 and p = 0.0001) in reperfused and nonreperfused AMI patients, respectively; f) a ratio of serum TnT at 16 h to serum TnT at 32 h after chest pain > 1 provided a good indication of reperfusion in thrombolytic treatment (94% efficiency).

Biochemical markers of hepatic fibrosis

Most liver diseases lead to a pathobiochemical reaction termed liver fibrosis. This is a dynamic process implying different rates of progression or regression. Thus, histological examination of a liver biopsy is essential for a diagnosis but biochemical tests are necessary for assessing the activity of the process and monitoring its evolution. We review the most important constituents of liver connective tissue and the biochemical tests developed for evaluating liver fibrosis. The aminopeptide of type III procollagen is the most widely used parameter: two different radioimmunoassays have been developed with different affinities for the two circulating forms of the molecule. The determination of serum P3P reveals an elevation of blood levels both in acute and chronic liver diseases. In the first, serum P3P is an index of hepatic necrosis and inflammation which correlates with other biochemical parameters. In the second it is an index of active fibrogenesis. Moreover, in primary biliary cirrhosis this parameter is an independent prognostic variable and an important predictor of survival. Other immunoassays exist for different collagen cleavage products, but their clinical value is not established. Laminin and fibronectin are the principal structural glycoproteins in liver. Fibronectin determination does not seem to be of clinical value in liver disease. In contrast, serum laminin correlates with the severity of portal venous pressure in advanced liver disease. Its concentration parallels the severity of varices and may indicate the risk of bleeding. Hyaluronate is a high molecular weight polysaccharide, raised serum concentrations reflect both its increased synthesis by activated fibroblasts and its impaired catabolism by the liver. Thus, it may be useful for evaluating and monitoring the progression of chronic liver disease. The measurement of the activity of prolyl 4-hydroxylase as well as that of lysine oxidase and other enzymes has been proposed, but their clinical value is not sufficiently demonstrated. A panel of tests (e.g., laminin, hyaluronate and the aminopeptide of type III procollagen) seems to be recommended for a biochemical assessment of liver fibrosis in clinical practice.

CA 19-9 and carcinoembryonic antigen in pancreatic cancer diagnosis

CA 19‐9 (Centocor, Malvern, PA) and carcinoembryonic antigen (CEA), two recently developed immunoradiometric assays utilizing monoclonal antibodies, were evaluated in the sera of 139 subjects in order to assay their individual and combined value in pancreatic cancer diagnosis and to assess the influence of jaundice. Sensitivity, specificity, and accuracy in detecting pancreatic cancer were 69%, 85%, and 54% for CA 19‐9; and 28%, 78%, and 6% for CEA, respectively. Combined evaluation gave the highest specificity (95%) when both, and the highest sensitivity (79%) when at least one, gave pathologic results. The receiver‐operating characteristic curves demonstrated that CA 19‐9 is more discriminating than CEA, for any serum value. A correlation between serum bilirubin and CA 19‐9 was demonstrated in pancreatic and extrapancreatic disease. CEA determination, performed using monoclonal antibodies, seems to be unsatisfactory as compared to CA 19‐9 in pancreatic cancer diagnosis, and combined assessment does not improve the results of CA 19‐9 alone. Jaundice may influence serum CA 19‐9 in pancreatic and extra‐pancreatic diseases. Cancer 57:1576–1579, 1986.

Oxygen derived free radicals in patients with chronic pancreatic and other digestive diseases.

To ascertain modifications in the activation products derived from oxygen free radicals in patients with chronic pancreatic and extra-pancreatic diseases, lipid peroxide activity was measured in the sera of 40 control subjects, 28 patients with pancreatic cancer, 49 with chronic pancreatitis, and 53 with extra-pancreatic diseases. In 142 of the subjects, elastase 1, amylase, and pancreatic isoamylase activities were also determined. Increased lipid peroxide activities were found in some patients with both chronic pancreatic and extra-pancreatic diseases. Patients with chronic pancreatitis studied during relapse had higher activities of lipid peroxides than those without active disease. No difference was found between the values in patients with pancreatic cancer with liver metastases and those without. Correlations were found between lipid peroxides and both amylase and pancreatic isoamylase activities; no correlation was detected between lipid peroxides and elastase 1. In benign biliary tract disease a correlation was detected between lipid peroxides and alanine aminotransferase and alkaline phosphatase activities. In all patients, however, a correlation was found between alkaline phosphatase and lipid peroxide activities. It is concluded that activation of oxygen derived free radicals occurs in chronic pancreatic as well as in extra-pancreatic disease; it seems to reflect the degree of inflammation.

Clinical Utility of TPS, TPA and CA 19-9 Measurement in Pancreatic Cancer

UNLABELLED The aims of this study were to (1) evaluate the diagnostic utility of a new tumor marker, TPS, with respect to TPA and CA 19-9 in patients with pancreatic cancer; (2) ascertain the reliability of the markers in predicting survival, and (3) evaluate the effect of liver dysfunction on the results. CA 19-9, TPA and TPS were measured in the serum of 19 control subjects, 42 patients with pancreatic cancer, 29 with chronic pancreatitis, and 52 with extrapancreatic diseases. CA 19-9 was confirmed to be the best serological indicator of pancreatic cancer, while TPA and TPS lacked both sensitivity and specificity. Pancreatic cancer patients with liver metastases had higher mean CA 19-9 and TPA, but not TPS, values than pancreatic cancer patients without metastases. A shorter survival time was associated with the presence of liver metastases and with higher serum tumor marker levels. CA 19-9, TPA and TPS were found to be correlated with liver function test results (ALT, ALP and bilirubin). IN CONCLUSION (1) TPS adds no significant information to that obtained using CA 19-9 in the diagnosis of pancreatic cancer; (2) CA 19-9 and TPA, but not TPS, are influenced by the presence of liver metastases; (3) the main factor to influence survival is advanced disease, which is in turn associated with higher tumor marker levels, and (4) liver dysfunction can influence not only CA 19-9 and TPA, as already described, but also TPS.

Serum arylesterase (paraoxonase) activity following myocardial infarction

Arylesterase (Aryl-ester hydrolase, paraoxonase, E.C. 3.1.1.2) hydrolyzes paraoxone, the active metabolite of the organophosphorous insecticide parathione, into p-nitrophenol and diethylphosphate. Although the natural substrate remains unknow, calcium (Ca’+) is known to be an essential co-factor [l]. The arylesterase assay was clinically applied in the histochemistry of tumors [2], hepatic diseases [3] and poisoning by organophosphates [4). Association between arylesterase and high-density lipoproteins (HDL) [5] has caused investigation of serum enzyme activity following myocardial infarction [6] to indirectly assess HDL concentration. Our study has two aims: (a) to confirm the association between serum arylesterase and HDL, which may play a protective role against coronary atherosclerosis; (b) to verify if in acute myocardial infarction variations of enzymatic activity occur which might have prognostic value.

Monitoring skeletal cancer metastases with the bone isoenzyme of tissue unspecific alkaline phosphatase.

The efficacy of bone alkaline phosphatase (ALP) isoenzyme measurement using lectin precipitation in confirming metastatic bone lesions was compared with total ALP and osteocalcin assay in serum. Sixty-five patients with cancer and metastases to bone (n = 44), liver (n = 15) or lymph nodes (n = 6) as well as 33 healthy adults were studied. Assay of bone ALP is as sensitive but more specific than assay of total ALP in the identification of bone metastases. On the other hand, bone ALP did not correlate with osteocalcin, as is the case in other bone diseases. In the serial monitoring of nine patients with skeletal metastases, bone ALP correlated well with the presence of pain and the progression or regression of metastatic spread.

Serum elastase 1 in chronic pancreatic disease

SummaryElastase 1 and immunoreactive trypsin were assessed by a RIA technique in the sera of 29 control subjects, 24 pancreatic cancer patients, 22 patients with chronic pancreatitis and 31 with extra-pancreatic diseases to ascertain and compare their usefulness in chronic pancreatic disease diagnosis. Increased levels of elastase 1 were detected in 60.9% of pancreatic cancer and in 61.1% of chronic pancreatitis patients; low values were found in only two subjects with pancreatic disease. A close correlation between the two enzymes was found in patients suffering from pancreatic cancer and chronic pancreatitis. These data suggest that serum elastase 1, as well as immunoreactive trypsin, is of limited value in chronic pancreatic disease diagnosis; increased levels of the two enzymes always occur simultaneously; low immunoreactive trypsin values together with normal elastase 1 serum levels are detectable in a number of patients with chronic pancreatitis and severe exocrine insufficiency.

Performance of a fluorescence polarization immunoassay system evaluated by therapeutic monitoring of four drugs.

Fluorescence polarization immunoassays (FPIA) for amikacin, gentamicin, quinidine, and theophylline (supplied by Roche Diagnostic Systems, made using a Cobas Fara centrifugal analyzer) were evaluated and compared with widely used monitoring analysis methods. For each drug, the between-assay imprecision was ascertained by calibration on the day of assay and by a stored calibration curve made at the beginning of the study. The precision of the amikacin and theophylline assays was acceptable [total coefficient of variation (CV) less than 7.5%] at all concentrations tested for each calibration mode. Imprecision of quinidine and gentamicin assays was significant at low concentrations (1.9 mg/L): total CV = 9.0% for quinidine assessed with stored calibration curve and total CV greater than 8.5% for gentamicin measured with the two calibration modes. The calibration curves for all four assays had a good stability (greater than 30 days). Linear regression analysis demonstrated close agreement between the FPIA (y) and the following comparative techniques (x): Abbott TDx assay for amikacin and gentamicin (r = 0.988, r = 0.974, respectively); Stratus fluorometric enzyme immunoassay for quinidine (r = 0.979); and EMIT Syva assay for theophylline (r = 0.993). It is concluded that fluorescence polarization immunoassay is a rapid and reliable method for the therapeutic monitoring of the four drugs tested. Moreover, the use of reagents on an instrument that can be implemented for a wide range of chemistries has significant advantages and cost benefits over dedicated instruments.

Tubular proteins and enzyme content in the amniotic fluid

Amniotic fluid is the product of many substances and fetal urine is considered to be one of the principal components. Only a few reports have been published describing the concentration of microglobulins and urinary enzymes in the amniotic fluid. We determined the levels of alpha 1-m, beta 2-m, AAP and NAG, in 154 samples of amniotic fluid (103 early determinations and 51 late determinations) as a function of gestational age. We observed a statistically significant decrease in concentration of alpha 1-m (P < 0.001), beta 2-m (P < 0.01) and AAP (P < 0.001) when early and late amniotic fluid samples were compared. A statistically significant increase of NAG (P < 0.01) and creatinine (P < 0.01) was also found. A significant correlation was observed between alpha 1-m and beta 2-m, and between AAP and NAG, respectively. The potential role of urinary enzyme and microglobulin determination in amniotic fluid as an index of fetal kidney development, is discussed.