Search PubMed⌕ Search

Biomedical subjects

M Plebani

Publications and source records attributed to M Plebani.

At least 217 records · Page 12Linked to original sources
PubMed1995

Multicentre evaluation of Capture Assay Radim Liquid Allergen for measurement of specific IgE antibodies.

A multicentre trial of Capture Assay Radim Liquid Allergen was performed to define the sensitivity, specificity and clinical reliability of the system in diagnostic allergology. The results of the evaluation were compared with clinical data and in vivo testing. Good agreement was obtained for Dermatophagoides pteronyssinus (D1), Cat's epithelium (E1), Betula verrucosa (T3) and Olea europea (T9), Artemisia vulgaris (W6) and Parietaria officinalis (W19). Some spreading of data was observed for Artemisia absinthium (W5), Cynodon dactylon (G2), and Lolium perenne (G5). We found a high number of negative cases for Alternaria alternata (M6). The advantages offered by the system are the automation, the small quantity of serum requested, the supply of quantitative results in international units of specific IgE, the user-friendly software. The data are sufficiently reliable for the diagnostic system to be introduced into the clinical laboratory allergological routine.

Adolescent↗
PubMed1995

The role of urokinase-type plasminogen activator and its inhibitor PAI-1 in gastric cancer.

BACKGROUND: It has been proposed that the serine protease urokinase-type plasminogen activator (UPA) and its inhibitor type-1 (PAI-1) may play an important part in cancer spread and metastasis. AIMS OF THE STUDY: 1. To determine the UPA, PAI-1 antigen levels in gastric cancer (GC) and in normal gastric mucosa far from the tumor (NORM). 2. To evaluate changes related to the presence of metastasis, tumor differentiation (grading) and histotype. PATIENTS AND METHODS: Samples of tumor and of normal mucosa were obtained from 25 GC patients undergoing surgery (17 males, 8 females, mean age 62, range 31-84). Antigen concentrations were measured using the ELISA method. RESULTS: Significantly higher UPA and PAI-1 antigen levels were found: 1. in GC vs. NORM tissue; 2. in patients with poorly and moderately differentiated GC vs. well-differentiated GC. UPA was significantly higher in GC with vs. without metastasis. PAI-1 was also higher, though not significantly so, in GC with metastasis than in GC without metastasis. CONCLUSION: Our results confirm that the serine protease UPA and its inhibitor PAI-1 play an important role in GC progression. Considering the higher protease levels detected in GC with metastases and poorer differentiation, UPA and PAI-1 might be useful for identifying gastric cancer patients with a poor prognosis.

Adult↗
PubMed1994

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.

Acetylglucosaminidase↗
PubMed1994

A new immunoassay for the measurement of myoglobin in serum.

Because the concentration of serum myoglobin (Mb) increases within 2 to 4 hours after the first sign of acute myocardial infarction, it has been proposed as an early marker of the condition. Our aim was to evaluate a new assay that provides a rapid, quantitative determination of Mb (Baxter Stratus Myoglobin) based on the radial partition technique. We compared the results obtained by this technique with those from nephelometric and radioimmunoassay methods. A significant agreement was observed, the correlation coefficients (r) being 0.999 and 0.996, respectively. The method evaluated provided good reproducibility with CVs between 3.14% and 4.87%, and its linearity and analytical sensitivity were satisfactory. The clinical evaluation of this assay demonstrates that Mb increases in serum of patients with acute myocardial infarction before total creatine kinase and creatine kinase MB isoenzyme. Mb concentration shows an early peak and earlier return to normal values after the necrosis compared to enzymatic activities. Moreover the assay is rapid and fully automated. The method is therefore considered appropriate for contributing to the early diagnosis of AMI in clinical laboratories.

Adolescent↗
PubMed1994

A new method for detecting anti Helicobacter pylori antibodies: an analytical and clinical evaluation.

The diagnosis of Helicobacter pylori (Hp) infection is an important goal in clinical practice. In this paper we evaluated 1. the analytical reliability of a new second-generation antigen based enzyme immunoassay (Cobas Core Anti Helicobacter pylori EIA) in detecting anti-Hp IgG antibodies, and 2. the behaviour of anti-Hp IgG in patients with chronic atrophic and non-atrophic gastritis as compared to healthy controls. The findings from the dilution curve, the values of intra and inter assay coefficients of variations (never above 10%) and of the recovery test (between 96 and 109%), confirm that the method is reliable. Serum IgG anti-Hp levels were found to be significantly higher in patients with histologically identified Hp infection, than in those negative at histology. Furthermore, the grade of histological positivity was correlated with serum IgG levels. However, we found a discrepancy between a low prevalence of Hp staining and a high prevalence of Hp seropositivity in patients with chronic atrophic or non-atrophic gastritis, but not in controls. This suggests that IgG serum determination may be more useful than histology in determining a present or previous infection in patients with chronic atrophic or non-atrophic gastritis.

Adult↗
PubMed1994

In vitro exposure to nitrogen dioxide (NO2) does not alter bronchial smooth muscle responsiveness in ovalbumin-sensitized guinea-pigs.

The aim of this study was to investigate whether in vitro exposure to NO2 affects responsiveness in ovalbumin-sensitized guinea-pig bronchi. Twenty-three animals were sensitized by three weekly intraperitoneal injections of 1 mg ovalbumin in saline with Freund's adjuvant; twenty-one control guinea-pigs received the diluent alone. From each animal, the two main bronchi were obtained and cannulated, then exposed in vitro to a constant intraluminal flow of: (i) either air or 2.5 ppm NO2 with four spikes of 10 ppm NO2 for 2 h; (ii) either air or 10 ppm NO2 for 4 h. A bronchial ring obtained from each animal before exposure was kept in aerated Krebs-Henseleit solution. Rings from bronchi exposed to air, NO2, or kept in Krebs solution were studied isometrically. We performed overall and non-adrenergic non-cholinergic voltage-response curves to electrical field stimulation, concentration-response curves to acetylcholine and to neurokinin A, followed by administration of 10 mg/ml ovalbumin. We did not find any significant difference in bronchial smooth muscle responsiveness between nonexposed, air-exposed and NO2-exposed bronchi, as well as between bronchi from control and sensitized animals. We conclude that in vitro exposure to NO2 does not alter bronchial smooth muscle responsiveness to either specific or non-specific stimuli.

Acetylcholine↗
PubMed1994

Different response to ursodeoxycholic acid (UDCA) in primary biliary cirrhosis according to severity of disease.

To evaluate the effect of ursodeoxycholic acid (UDCA) treatment according to the severity of primary biliary cirrhosis, a long-term prospective open trial in 54 consecutive PBC patients, 19 with histological stage I-II, 24 stage III, and 11 stage IV was carried out. UDCA was administered at a dosage of 250 mg twice a day. Clinical and biochemical assessment (AST, ALT, alkaline phosphatase, GGT, bilirubin) were done initially and every six months. Serum hyaluronate (HY) and type III procollagen amino propeptide (PIIIP) were also evaluated, as they are considered markers of fibrosis and prognosis. All patients were followed-up for at least two years (24-36 months); results were analyzed at 24 months after treatment. The composite pruritus score failed to show significant changes during UDCA treatment, while intensity score demonstrated a significant reduction from the 6th month. Patients with histological stage I-II disease had a significant decrease of liver enzymes (AST, ALT, alkaline phosphatase, GGT) after six months and maintained the levels up to 24 months. The patients with histological stage III disease showed a significant decrease of AST, ALT, alkaline phosphatase (but not GGT) up to month 18; subsequently AST and ALT serum levels increased, reaching values comparable to baseline by 24 months. In patients with histological stage IV disease no significant change in liver enzymes was observed during the follow-up. HY and PIIIP serum levels failed to show significant changes during UDCA treatment in the three groups of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Cholestyramine Resin↗
PubMed1994

Pepsin concentration in gastroduodenal biopsy homogenates in chronic ulcer disease.

A modification of Berstad's spectrophotometric method was tested and proved capable of detecting pepsin concentrations in mucosal perendoscopic biopsy homogenates. The relationship between this parameter and pepsin in gastric juice and pepsinogen group I in serum and in biopsy homogenates was analyzed. From the biochemical point of view, the assay was found sufficiently accurate. Mucosal pepsinogen group I, but not mucosal pepsin, concentration was found higher in gastric and duodenal ulcer patients than in controls. Patients with corpus-fundic gastric ulcer showed significantly lower mucosal pepsin and mucosal pepsinogen group (PG) I. Aging and smoking did not influence either parameter but male duodenal ulcer subjects presented higher mucosal pepsinogen group I concentration. The lack of any relationship between serum and mucosal PG I and between pepsin in gastric juice and in mucosa raises a question, at least in methodological terms, about the validity of using serum pepsinogen group I and pepsin as indicators of peptic output.

Adult↗
PubMed1994

Are tryptase and cathepsin D related to Helicobacter pylori infection and mucosal gastrin in peptic ulcer?

The pathogenesis of peptic ulcer is a complex phenomenon and several factors are thought to be involved in this process. Among others, Helicobacter pylori infection, hypergastrinaemia and some proteases seem to play an essential role in inducing peptic ulceration. We investigated whether tryptase (a serine endoprotease released by mast cells) and cathepsin D (a lysosomal hydrolase which seems able to derange the extracellular matrix) play a part in peptic ulcer disease and whether they are linked to Helicobacter pylori infection and mucosal content of gastrin. We studied 13 controls, 25 patients with gastric ulcer, 47 with duodenal ulcer and 11 with duodenitis. Tryptase and cathepsin D were measured in mucosal biopsy specimens (body and antrum of the stomach and duodenum) using IRMA methods. Gastrin was assayed in the antral mucosa by means of a RIA method. Helicobacter pylori infection was histologically evaluated (Giemsa). Tryptase and cathepsin D levels were higher (25%) in patients with active peptic ulcer, whether gastric or duodenal. The mucosal content of cathepsin D, but not that of tryptase, was associated with Helicobacter pylori infection. Tryptase, on the other hand, was related to gastrin content. No correlation was found between the two enzymes. It is concluded that tryptase and cathepsin D probably reflect different pathophysiological modifications in ulcer disease. Cathepsin D seems to be mainly related to the phlogistic reaction of the mucosa to Helicobacter pylori infection; tryptase may reflect and indirect link between the action of gastrin and the function of mast cells.

Adult↗
PubMed1994

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.

Adult↗
PubMed1994

Laboratory medicine in ulcer disease.

The role of laboratory medicine in ulcer disease is poorly defined. However there is increasing evidence of the clinical usefulness of some laboratory tests that investigate secretory functions and defensive properties of the stomach, gastrointestinal hormones and Helicobacter pylori infection. These tests may modify the clinical management of patients with peptic ulcer by identifying H. pylori positive subjects, patients with high acid output, patients who do not respond to antisecretory therapy, and patients with high gastrin levels in whom Zollinger-Ellison syndrome may be suspected. Here we review the clinical value of laboratory tests in ulcer disease, particularly as concerns the cost/benefit ratio. The relative merits of these tests are described giving an indication of their possible role in the diagnostic algorithm.

Chemistry, Clinical↗
PubMed1994

Identification of subcellular targets and sensitive tests of ethanol-induced damage in isolated rat gastric mucosal cells.

BACKGROUND/AIMS: The mechanisms of chemically induced injury are poorly understood. The purpose of this study was to develop a rapid method for isolation of gastric mucosal cells (GMCs) and sensitive tests for investigating cell damage and protection. METHODS: GMCs were prepared from rat glandular stomach with pronase and ethylene glycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid (EGTA) and kept in albumin-containing, albumin-free, or Hank's solutions. Initial cell viability and responsiveness were tested with trypan blue exclusion, and stimulation or inhibition of pepsinogen secretion were tested with carbachol, 16,16-dimethyl prostaglandin E2, or carbachol plus atropine. Plasma membrane damage was assessed by trypan blue exclusion, lactate dehydrogenase or cell protein leakage, mitochondrial integrity by succinic dehydrogenase activity, and nuclear lesions by ethidium bromide DNA fluorescence. RESULTS: Incubation of GMC with ethanol resulted in 50% lethal dose for ethanol values of 12.3%, 7.4%, and 10.9% by trypan blue exclusion; 10.1%, 9.4%, and 9.1% by lactate dehydrogenase leakage; 12.8%, 10.0%, and 10.4% by succinic dehydrogenase; and 14.1%, 13.0%, and 11.5% by ethidium bromide DNA by binding using albumin-containing, albumin-free, and Hank's solutions, respectively. CONCLUSIONS: Rat GMC with high and long viability can be isolated by low concentrations of pronase and EGTA. The adapted biochemical and microscopic methods are suitable for parallel examination of chemical injury of plasma membrane, mitochondria, and nuclei. Albumin increased ethanol 50% effective concentration to GMC. A combination of biochemical and morphological methods with ethanol-induced injury to GMC is proposed for direct cytoprotection investigations.

Animals↗
PubMed1994

Serum CA549 in primary breast cancer: comparison with CA15.3 and MCA.

We carried out a comparison of three commonly used mucin markers, CA549, CA15.3 and MCA. Serum samples from 184 healthy women and 237 patients with primary breast cancer were evaluated. The markers were measured using commercially available immunometric assays. Like CA15.3 and MCA, CA549 was significantly associated with tumour size and lymph node status, being an effective indicator of tumour bulk. CA549 was significantly correlated with both CA15.3 and MCA. Positive/negative concordance rate was very good (93.7%) between CA549 and MCA. Conversely, CA15.3 was positive and CA549 negative in 20.4% of cases. Axillary status was not significantly different in the latter group of patients and in cases in which CA15.3 and CA549 showed concordant results. From the present findings we draw the following major conclusions: 1. CA549 and MCA are highly correlated and their association should not provide additional information; however, they should not be considered interchangeable since they may behave differently in individual cases. 2. CA549 and CA15.3, although well correlated, are discordant in a significant number of cases. Longitudinal studies are needed to verify the usefulness of the association between the two markers. 3. The three evaluated mucin markers are not interchangeable in individual patients; if a patient is monitored with a marker, she should be followed up with the same marker.

Adult↗
PubMed1994

Beta-cell function in pancreatic adenocarcinoma.

To evaluate beta-cell function in patients with pancreatic cancer, the glucagon stimulation test was performed in seven patients with pancreatic adenocarcinoma, seven patients with type I diabetes mellitus, seven patients with type II diabetes mellitus, and in seven healthy controls. C-peptide serum levels were determined before and after a 1-mg i.v. glucagon injection. Basal C-peptide values were normal or slightly increased in pancreatic cancer and type II diabetic patients and low in type I diabetic patients. Following glucagon stimulation, no significant increase was observed in C-peptide values of type I diabetics and pancreatic cancer patients, whereas significant increases occurred in controls and type II diabetics. It is concluded that the altered beta-cell function found in pancreatic cancer patients may lead to hyperglycemia, which is frequently associated with this tumor type.

Adenocarcinoma↗