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Biomedical subjects

M Plebani

Publications and source records attributed to M Plebani.

At least 271 records · Page 15Linked to original sources
PubMed1991

Comparison of two newly identified tumor markers (CAR-3 and DU-PAN-2) with CA 19-9 in patients with pancreatic cancer.

We compared the diagnostic utility of DU-PAN-2 and CAR-3 with that of CA 19-9 in differentiating pancreatic cancer (23 patients) from chronic pancreatitis (16 patients) and various extra-pancreatic diseases (28 patients) mainly of the upper gastrointestinal and biliary tract. The influence of some pathophysiologic variables on the three markers was also assessed. The sensitivities of the three markers in detecting pancreatic cancer were: CA 19-9, 83%; DU-PAN-2, 56%; and CAR-3, 39%. In patients with chronic pancreatitis and extra-pancreatic diseases, CA 19-9 gave the highest number of false positives. Receiver-operating characteristic curves showed that the ability of CAR-3 to discriminate between pancreatic cancer and other diseases was similar to that of CA 19-9, whereas DU-PAN-2 was a less reliable discriminator. Correlations were found between the behavior of all three markers and that of the cholestasis indices (ALP and GGT). Our findings indicate that DU-PAN-2 and CAR-3 serum determinations do not provide any more information than does CA 19-9 alone. The latter remains the marker of choice in the differential diagnosis of pancreatic cancer, even though it cannot be considered a definitive aid. Serum levels of all three markers increase in the presence of extra-hepatic cholestasis, possibly due to interference with the hepatic clearance of glycoproteins and destruction of ductal biliary epithelium.

Adult↗
PubMed1991

CA 50 determination in body fluids: can we screen patients at risk for gastric cancer?

CA 50 (a tumor-associated gangliosidic antigen) levels have been determined by an RIA test in serum, gastric juice and urine of patients undergoing upper gastrointestinal tract endoscopy: 22 control subjects (no macroscopic or microscopic lesions), 29 patients with chronic atrophic gastritis, 20 with epithelial dysplasia and 16 with gastric cancer entered the study. Gastric juices were also tested for pH, protein concentration and specific gravity, urines for protein concentration and osmolarity. Serum and gastric juices were also tested for CEA levels and the results obtained with the two markers compared. In patients with gastric cancer, CA 50 gastric juice levels were statistically higher than in controls; a wide overlap was however present among groups, and sensitivity and specificity were respectively 38% and 85% for serum and 69% and 82% for gastric juice. Sensitivity and specificity were respectively 23% and 89% for CA 50 determination in urines. In this case, no statistically significant difference was observed between gastric cancer and control patients. A trend toward higher median values was observed in advanced with respect to early gastric cancer. A correlation was found between gastric juice and serum CA 50 levels, as well as between serum and urine levels of the marker. A correlation was also observed between CA 50 values and protein concentration in gastric juice and with osmolarity in urines. Overall, CA 50 levels were statistically higher in patients with intestinal metaplasia than in those who did not present the lesion. Increased CA 50 gastric juice levels are also observed in patients with chronic atrophic gastritis and epithelial dysplasia. CA 50 gastric juice and urine levels appear to be dependent, at least in part, on the concentration of the fluid.

Adult↗
PubMed1991

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.

Biomarkers↗
PubMed1991

Precipitation method for separating and quantifying bone and liver alkaline phosphatase isoenzymes.

We evaluated a method for quantifying bone isoenzyme of alkaline phosphatase (ALP) which utilizes wheat-germ lectin to precipitate this fraction. In precision studies, CVs ranged from 3.2 to 11.4% (within-day) and from 3.7 to 11.5% (day-to-day). The assay procedure was linear to 1100 U/L and was easily adapted to automated kinetic measurement. Comparison of the precipitation method with an affinity electrophoretic method, which utilizes cellulose acetate as a support, demonstrated a satisfactory coefficient of correlation (r = 0.886). The reference range was determined in sera from 188 healthy adult subjects. The distribution of bone ALP values was also studied in 73 healthy children and in 30 healthy adolescents. To evaluate the clinical applicability of the method, the bone isoenzyme was determined in samples from several groups of subjects (pregnant women, patients with hepatobiliary diseases, patients with hepatocellular carcinoma without skeletal involvement, and patients with bone, liver or lymph node metastases). We found the method suitable for routine determination of bone alkaline phosphatase and for the screening of bone metastases. Because of its technical simplicity and satisfactory analytical performance, it can be used instead of the heat-inactivation procedure.

Adolescent↗
PubMed1991

Urinary kallikrein excretion in chronic pancreatic diseases.

Variations in urinary kallikrein in pancreatic diseases were ascertained, and possible influencing factors were investigated. Serum amylase and urinary excretion of glandular kallikrein, pancreatic ribonuclease (RNase), gamma-glutamyltransferase (GGT) and amylase were measured in 24 control subjects, 39 patients with pancreatic cancer, 49 with pancreatitis and 63 with extra-pancreatic diseases. Urinary kallikrein was found to be elevated in a substantial number of patients with pancreatitis. Higher levels were detected in patients with a relapse, which was diagnosed using clinical and biochemical examinations. RNase was also increased in a high number of patients with pancreatic diseases, but was not correlated with pancreatic damage. In patients with pancreatitis, a correlation was found between urinary kallikrein and RNase excretions. No correlations were found between kallikrein and serum or urinary amylase and GGT. We can conclude that urinary kallikrein excretion increases in pancreatitis, especially when a phlogistic involvement of the pancreas is present; this condition may lead to a release of this ultrafiltrable enzyme in the circulation. Renal tubular damage, which determines a reduced reabsorption of this enzyme, seems to play a concomitant but minor role in this process.

Adult↗
PubMed1991

Does serum CAR-3 play a role in pancreatic cancer diagnosis?

A new tumour marker, CAR-3, was isolated using the monoclonal antibody technique and measured in the sera of 27 patients with pancreatic cancer, 25 chronic pancreatitis, 30 extra-pancreatic diseases and in that of 18 healthy controls in order (1) to evaluate the diagnostic role of CAR-3 in patients with pancreatic cancer and (2) to ascertain whether liver dysfunction influences CAR-3 serum levels. The increased levels were found in 12/27 patients with pancreatic cancer (sensitivity 44.4%). No increase was found in patients with chronic pancreatitis, whereas abnormal levels were found in patients with other gastrointestinal diseases, especially those of the liver and biliary tract. Correlations were found between serum CAR-3 and (1) total bilirubin and (2) alkaline phosphatase. In conclusion, CAR-3, an antigen structurally related to CA 19-9, does not appear to be accurate enough to be considered a tumour marker. Cholestasis seems to increase CAR-3 levels as well as those of other glycoproteic tumour markers, probably by interfering with the hepatic clearance of these substances.

Adult↗
PubMed1991

Hepatic changes and serum ferritin in pancreatic cancer and other gastrointestinal diseases: the role of cholestasis.

Serum ferritin, prealbumin, pseudocholinesterase, alpha-1-antitrypsin and caeruloplasmin were determined in control subjects and patients with pancreatic cancer, chronic pancreatitis or extra-pancreatic disease mainly of gastrointestinal origin, in order to investigate the different hepatic changes which influence serum ferritin in chronic pancreatic and other digestive diseases. Increased circulating ferritin was found in pancreatic cancer and extra-pancreatic disease when compared to controls. Correlations were detected between ferritin and the other proteins investigated and between ferritin and total bilirubin, alkaline phosphatase and alanine aminotransferase. Multiple regression analysis demonstrated that cholestasis accounts for 45% of circulating ferritin, the acute-phase response accounted for 18% and decreased liver function accounted for 11%. We conclude that the increase in serum ferritin in chronic pancreatic and other gastrointestinal diseases largely depends on liver changes, with cholestasis probably playing a primary role.

Adult↗
PubMed1991

Pepsinogen A/pepsinogen C or pepsinogen A multiplied by gastrin in the diagnosis of gastric cancer?

Being pepsinogen A (PGA) levels generally reduced and pepsinogen C (PGC) increased in gastric cancer patients, PGA/PGC ratio has been proposed as a useful marker of the tumour. We tested PGA, PGC and Gastrin (G) levels in patients with gastric cancer (39) and, as a control, in patients with epithelial dysplasia (21), chronic atrophic gastritis (57), gastric ulcer (11) or subjects lacking major or minor endoscopic and microscopic changes at gastroscopy (48). PGA and PGA/PGC levels were significantly reduced in gastric cancer patients (p less than 0.005 and p less than 0.0001 respectively with analysis of variance). Gastrin levels were also reduced in the same patients (p less than 0.005). We therefore adopted an index number (PGA x Gastrin) which was also dramatically reduced in gastric cancer (p less than 0.005); using an arbitrarily chosen cut-off, the "marker" showed very high sensitivity (76%), specificity (96%) and overall accuracy (74%, by Youden J test). We therefore suggest the use of the index number PGA x G in the diagnosis of gastric cancer, as the most useful gastrin presently available, to our knowledge.

Biomarkers, Tumor↗
PubMed1991

Role of local and systemic factors in increasing serum glycoprotein markers of pancreatic cancer.

This study was performed in order to evaluate the role of various local and systemic alterations in influencing serum glycoproteic markers in patients with pancreatic cancer, and in healthy and diseased controls. Cancer antigen 19-9 (CA 19-9), carcinoembryonic antigen (CEA), and ferritin were determined in the sera of 23 control subjects, 30 patients with pancreatic cancer, 27 with chronic pancreatitis, and 27 with extra-pancreatic diseases mainly of gastrointestinal origin. A number of acute-phase proteins and indices of liver function and cholestasis were also assayed. The three antigens increased only in patients with pancreatic cancer. Higher CA 19-9 and CEA, but not ferritin, levels were found only in patients with hepatic metastases. Acute-phase proteins and synthetic functional indices were found to be higher and lower, respectively, in patients with pancreatic malignancy when compared with controls. Multiple regression analysis documented the dependence of circulating ferritin, but not of CA 19-9 and CEA, on the systemic indices. Canonical correlation showed a similar trend for CA 19-9 and CEA, which differed from that of ferritin. Ferritin was found to depend on the presence of systemic and hepatic alterations, especially of cholestasis. We can conclude that the variations of serum glycoprotein markers in patients with pancreatic cancer depend on various regional and systemic factors. CA 19-9 and CEA are related mainly to the extent of the neoplasia. The influence of a decreased liver function capacity associated or not to cholestasis and the interrelation with the acute-phase response may also be suggested. Ferritin, on the other hand, is related to a higher degree than CA 19-9 and CEA to hepatic dysfunction and also behaves similar to an acute-phase protein.

Adult↗
PubMed1991

Sex hormone changes in post-menopausal women with primary biliary cirrhosis (PBC) and with cryptogenic chronic liver disease.

Sex hormones and sex hormone binding globulin (SHBG) have been studied in 32 female post-menopausal patients (16 with Primary Biliary Cirrhosis (PBC) and 16 with cryptogenic chronic liver disease (CLD). Dehydroepiandrosterone-sulfate (DHEA-S) serum levels were significantly higher in PBC compared to CLD subjects (p less than 0.005). In PBC DHEA-S concentration was higher in precirrhotic than in cirrhotic patients (p less than 0.02). SHBG was raised in both PBC and CLD patients but higher in CLD compared to PBC subjects (p less than 0.002). PBC reveals a sex hormone pattern similar to post-menopausal subjects with breast cancer. These results suggest that sex hormone alteration is present in females with different types of liver disease, but the metabolic pattern is not due to liver disease per se.

Aged↗
PubMed1991

Theophylline inhibits early and late asthmatic reactions induced by allergens in asthmatic subjects.

To determine whether oral slow-release theophylline inhibits asthmatic reactions and the associated increase of airway responsiveness to methacholine induced by allergens, we examined six asthmatic subjects who developed a dual asthmatic reactions after allergen bronchoprovocation with Dermatophagoides pteronyssinus or with grass pollen. We gave oral slow-release theophylline and placebo to each subject for seven days in two series of experiments in a double-blind, randomized, crossover study. The individual daily dose of theophylline (4.7 to 16.6 mg/kg/day, divided into two doses) was calculated for each subject by measuring individual theophylline clearance and optimal daily dosage. During treatment with placebo, the subjects developed dual asthmatic reactions, ie, FEV1 decreased from 4.1 +/- 0.17 L before bronchoprovocation to 3.2 +/- 0.14 L at 15 minutes and to 3.2 +/- 0.19 L at seven hours after allergen bronchoprovocation. By contrast, during active treatment FEV1 decreased from 4.2 +/- 0.28 L to 3.9 +/- 0.26 L at 15 minutes, and to 3.8 +/- 0.13 L at seven hours (both cases, P less than .03 compared with placebo). Mean serum theophylline concentration was 13.2 +/- 0.6 mg/L. Although 1 week's treatment with slow-release theophylline did not modify significantly either prechallenge airway responsiveness to methacholine or its increase after allergen inhalation challenge, in five out of six subjects theophylline significantly inhibited the increase of airway responsiveness to methacholine induced by allergens compared to placebo and control day (P less than .05). These results suggest that slow-release theophylline may inhibit allergen-induced asthmatic reactions and the associated increase of airway responsiveness, suggesting some antiinflammatory effects for this drug.

Administration, Oral↗
PubMed1991

[Basal and postprandial blood gastrin in peptic ulcer. The physiopathological aspects in relation to different sites of the lesion].

A different pathophysiological mechanism is widely accepted for gastric and duodenal ulcer. In particular, the exact role of gastrin in the determinism of non hormono-dependent peptic ulcer disease is not completely clarified. Therefore, the aim of present study was to analyse fasting and post-prandial serum gastrin levels in 99 duodenal ulcer patients, 17 gastric ulcer patients and 11 subjects presenting an association of gastric and duodenal ulcer. The possible correlation between post-prandial gastrin concentrations and basal and maximal acid output in the 3 fasting serum gastrin levels appear not different among the 3 classes of patients, while post-prandial gastrin concentrations are statistically higher at 15 minutes in duodenal ulcer patients and in subjects with the association of gastric and duodenal ulcer as compared to gastric ulcer patients. Mean fasting and stimulated gastrin levels are higher in gastric ulcer females than in males during the entire test and with statistically difference at 30 minutes. The concentrations of the hormone are not different in males of the 3 groups of patients at basal time, while are statistically lower at 15 and 30 minutes in gastric ulcer males compared to the males with duodenal ulcer and the association of the localization. Finally, positive correlation has been observed between BAO and MAO and post-prandial gastric concentrations in the 3 groups of patients, while there is an inverse correlation between the previous parameters as regards sex, both in gastric and duodenal ulcer.

Adult↗
PubMed1990

Eicosanoid release from human bronchial epithelial cells upon exposure to toluene diisocyanate in vitro.

Epithelial injury and inflammation are involved in airway hyperresponsiveness and asthma induced by toluene diisocyanate. In that isocyanates are insoluble and highly reactive compounds, bronchial epithelial cells may represent the most important target cells of their toxic effect. We hypothesized that damage to airway epithelium by toluene diisocyanate may result in the release of metabolites of arachidonic acid, which are known to promote inflammation and to alter epithelial cell function and airway smooth muscle responsiveness. To test this hypothesis we examined eicosanoid products in the culture media of bronchial epithelial cells exposed in vitro to 8 and 18 ppb toluene diisocyanate. Epithelial cells derived from human bronchi obtained at surgery were cultured to confluency on collagen-coated microporous membranes. Those cells, which expressed differentiated characteristics of epithelial cells (they showed keratin-containing filaments and had a cobblestone appearance), were alternatively exposed to toluene diisocyanate or air for 30 min in a specially designed in vitro chamber. The production of metabolites of arachidonic acid was assessed by measuring the release of immunoreactive products into the cell medium at the end of the exposure and during a 2 hr period after exposure. This method revealed a predominant isocyanate-induced release of immunoreactive 15-hydroxyeicosatetraenoic acid. Release rate of this compound tended to be dose-related and was associated with cell damage as assessed by the release of lactate dehydrogenase in the medium.

Arachidonic Acid↗
PubMed1990

Measurement of melatonin in blood by radioimmunoassay. Analytical considerations and clinical usefulness.

Melatonin assay has proved to be clinically useful for the diagnosis and investigation of several diseases (e.g., Cushing's syndrome, depressive disorders). We have evaluated the analytical performance of a radioimmunoassay for the determination of melatonin in plasma. The interference of some anticoagulants has been investigated, as well as the preliminary extraction of the hormone using a liquid-liquid and a solid-phase extraction method. The variation coefficients of the assay, within and between runs, were between 3.8% and 9.2% and between 4.1% and 10.5%, respectively. The well-documented circadian rhythm of melatonin secretion was confirmed in our healthy subjects. Preliminary results appear to confirm the significance of melatonin measurement in neurosurgical patients.

Adult↗
PubMed1990

Fluorescence polarization immunoassay for cyclosporine A determination in whole blood.

A fluorescence polarization immunoassay (FPIA) for cyclosporine A (CsA) determination in blood was evaluated. The method demonstrated a good reproducibility both in within-run and between-run assays. The linearity range was 35-990 micrograms/L. Comparison of measurements in patients' whole blood with radioimmunoassay results showed higher estimates by the FPIA despite the good correlation coefficient. Finally, a poor agreement was observed between the evaluated method and the high-performance liquid chromatographic technique for CsA determination.

Adolescent↗