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Biomedical subjects

M Plebani

Publications and source records attributed to M Plebani.

At least 181 records · Page 10Linked to original sources
PubMed1996

Gastric juice polymerase chain reaction: an alternative to histology in the diagnosis of Helicobacter pylori infection.

BACKGROUND: Infection from Helicobacter pylori plays a role in several gastroduodenal diseases. The recent availability of molecular techniques, particularly the polymerase chain reaction (PCR), allows us to detect small amounts of this bacterium. The aims of this study were to compare PCR and histological findings and to ascertain the clinical usefulness of H. pylori PCR identification in different biological samples. MATERIALS AND METHODS: We studied 94 consecutive patients. Saliva, gastric juice, and four antral and four body biopsies were obtained from each patient. H. pylori was evaluated histologically in two antral and two body biopsies (Giemsa or Warthin-Starry stain). After extraction, DNA was submitted for PCR amplification using the two primers HPU1 and HPU2, which amplified a 411-bp product from the urease gene A. RESULTS: Forty-nine patients were H. pylori-positive at histological workup. The sensitivity of PCR was 92% for gastric juice, 73% for antral biopsies, 61% for body biopsies, and 13% for saliva. Of the 45 H. pylori-negative patients at histological assessment, 7 (16%) had positive findings on PCR, mainly when gastric juice was examined. CONCLUSIONS: These results indicate that PCR is as sensitive as histological assessment. We suggest that PCR H. pylori detection in gastric juice is a sensitive method for diagnosing this infection.

Adult↗
PubMed1996

The coeliac iceberg in Italy. A multicentre antigliadin antibodies screening for coeliac disease in school-age subjects.

BACKGROUND: Recent studies suggest that coeliac disease (CD) is one of the commonest, life-long disorders in Italy. The aims of this multicentre work were: (a) to establish the prevalence of CD on a nationwide basis; and (b) to characterize the CD clinical spectrum in Italy. PATIENTS AND METHODS: Fifteen centres screened 17,201 students aged 6-15 years (68.6% of the eligible population) by the combined determination of serum IgG- and IgA-antigliadin antibody (AGA) test; 1289 (7.5%) were IgG and/or IgA-AGA positive and were recalled for the second-level investigation; 111 of them met the criteria for the intestinal biopsy: IgA-AGA positivity and/or AEA positivity or IgG-AGA positivity plus serum IgA deficiency. RESULTS: Intestinal biopsy was performed on 98 of the 111 subjects. CD was diagnosed in 82 subjects (75 biopsy proven, 7 not biopsied but with associated AGA and AEA positivity). Most of the screening-detected coeliac patients showed low-grade intensity illness often associated with decreased psychophysical well-being. There were two AEA negative cases with associated CD and IgA deficiency. The prevalence of undiagnosed CD was 4.77 x 1000 (95% CI 3.79-5.91), 1 in 210 subjects. The overall prevalence of CD, including known CD cases, was 5.44 x 1000 (95% CI 4.57-6.44), 1 in 184 subjects. The ratio of known to undiagnosed CD cases was 1 in 7. CONCLUSIONS: These findings confirm that, in Italy, CD is one of the most common chronic disorders showing a wide and heterogeneous clinical spectrum. Most CD cases remain undiagnosed unless actively searched.

Adolescent↗
PubMed1996

Pancreatic exocrine involvement in primary Sjögren's syndrome.

Exocrine pancreatic involvement of primary Sjögren's syndrome (SS) was studied. Pancreatic enzyme levels (total amylase, pancreatic isoamylase and immunoreactive trypsin) along with anti-ductuli antibodies (Ab) were studied in 77 patients with primary SS. In 10 patients with normal and 10 with abnormal enzyme levels pancreatic CT scans were also obtained. All enzyme levels were significantly increased in comparison to the control group. Immunoreactive trypsin was found to be the most frequently increased enzyme (35.3% of pSS patients). Anti-ductuli Ab were not found in any patient. Pancreatic CT scans were normal in all subjects with enzymatic increase, whereas 2 abnormal scans were demonstrated in patients without enzyme changes. Our study suggests that exocrine pancreatic involvement is frequent when measured by enzyme levels. Nevertheless, we were unable to demonstrate any morphological lesion by CT scan.

Abdominal Pain↗
PubMed1996

Helicobacter pylori serology in patients with chronic gastritis.

OBJECTIVES: Helicobacter pylori (Hp) infection is known to cause several gastroduodenal diseases. In patients with non-ulcer dyspepsia, we assessed the link between Hp infection and gastric mucosal inflammation, as well as the influence of Hp and inflammation on the serum levels of anti-Hp antibodies (IgG), pepsinogen A (PGA), pepsinogen C (PGC), and gastrin. METHODS: Entering the study were 221 patients with non-ulcer dyspepsia, all of whom underwent upper gastrointestinal endoscopy. RESULTS: Of the 221 patients investigated, 135 (61%) were Hp positive. The higher the bacterial load, the worse the associated gastritis, the gastric antrum and body being considered. All of the serological indices studied were found to be influenced by gastritis. Serum IgG satisfactorily discriminated between Hp-positive and Hp-negative subjects, with a sensitivity of 84% and a specificity of 86%. PGC, PGA, and gastrin were less accurate. Only PGC only found to be correlated with Hp load. The product of IgG and PGC improved the diagnostic accuracy of IgG alone. CONCLUSIONS: Hp infection, frequently found in patients with non-ulcer dyspepsia, is associated with gastric mucosal inflammation; of the indices studied, serum IgG and PGC most accurately indicated Hp infection, and their product may be proposed as an aid in diagnosing Hp infection in dyspeptic patients.

Adult↗
PubMed1996

[Analytical evaluation of an automated hematologic analyzer: Cell Dyn 3500].

In this study we evaluated the analytical performances of the Cell Dyn 3500, an automated hematology analyzer that provides the electronic and optical detection of leukocyte count and the complete cell counts in samples of whole blood. The protocol included evaluation of complete blood count and differential leukocyte count parameters, using the ICSH and the NCCLS H20-A protocols. Technical performances with regards, to linearity, carry over, precision and stability were quite well acceptable; the accuracy showed a good agreement between Cell Dyn 3500 and instruments used in our laboratory for the major hematologic indices and a good correlation for neutrophils, lymphocytes and eosinophils compared with the manual count.

Autoanalysis↗
PubMed1996

[The role of the laboratory in the diagnosis and monitoring of Helicobacter pylori infection].

The diagnosis of Helicobacter pylori infection represents a fundamental step for a correct clinical approach to the patient with gastritis, peptic ulcer or gastric adenocarcinoma or lymphoma. Upper gastrointestinal endoscopy has first to be made in order to obtain gastric juice and mucosal biopsies, where Hp can be found. Two different procedures are recommended to diagnose Hp infection (e.g. urease test and histology or culture). The identification of specific DNA sequences with the polymerase chain reaction represents a sensitive and specific method to diagnose Hp infection. Serum anti Hp antibodies, pepsinogen A and C determination is recommended at diagnosis and during the follow-up to assess the success of therapy.

Chronic Disease↗
PubMed1996

Isolated rat gastric mucosal cells: optimal conditions for cell harvesting, measures of viability and direct cytoprotection.

Controversial data have been obtained with direct cellular protection by prostaglandins and sulfhydryls. In the present studies, we compared the merits and liabilities of currently available cell viability assays, some of which have not been previously employed in studies of the gastric mucosa. We also tested the hypothesis that length of incubation of isolated cells with protective agents might influence the degree of cellular damage. Gastric mucosal cells were isolated from nonfasted rats and digested with various concentrations of pronase and/or EGTA. Cell viability was assessed by trypan blue and fast green exclusion, fluorescein diacetate hydrolysis, chromium release, LDH release, mitochondrial succinate dehydrogenase activity and nuclear fluorescence induced by ethidium bromide. The experiments revealed that both pronase and EGTA are needed to obtain mucosal cells with optimal yield and initial viability and that sequential additions of pronase (30 min) and EGTA (30 min), rather than their combination (60 min), increased viability without decreasing yield. Cell viability and yield were better when pronase was used in the first incubation. For LD50 determinations, a cell suspension was incubated with ethanol (0%-15%) for 5 min. For studying the effects of protective agents, the cells were pretreated with 16,16-dmPGE2 or cysteamine HCl at 37 degrees C for 30 min before a 5-min exposure to 7.5% or 15% ethanol. The LD50 value for ethanol injury was approximately 15% for all assays except LDH, where the LD50 value was 8.5%. Preincubating gastric mucosal cells for 30 min with 16,16-dmPGE2 or cysteamine resulted in no preservation of cell viability. However, when cells were preincubated with one of the protective agents for 60 min and then exposed to 8% or 10% ethanol for 5 min, partial protection was observed when assessed by succinate dehydrogenase activity and, in certain cases, by LDH release. We conclude that all seven cell viability assays yield a measurable LD50 value for ethanol-induced cell injury, but the results may vary by as much as 82%. Low concentrations of both pronase and EGTA are needed to obtain isolated mucosal cells with both high yield and initial viability. Biochemical measures of mitochondrial activity and nuclear damage provide reliable evidence of cell viability and should be used to complement membrane permeability assays. Long preincubation of cells (60 min) with protective agents resulted in only slight protection of mitochondrial function, in contrast to the rapid induction of gastroprotection seen with these compounds in vivo. We therefore surmise that processes that contribute to organ protection occur faster and more efficiently than those that control direct cell injury and protection.

Animals↗
PubMed1996

Fluoroenzymometric method to measure cardiac troponin I in sera of patients with myocardial infarction.

The aim of our study was to evaluate the clinical relevance of serum troponin I (TnI) as a marker of ischemic myocardial injury by using an automated fluoroenzymometric assay. The reference range for serum TnI was established by measuring serum TnI concentrations in blood from 75 healthy donors. The concentration was then compared with serum creatine kinase (CK) activity, CK-MB mass, and myoglobin concentrations in 20 patients with myocardial infarction diagnosed according to the WHO criteria, 20 patients with chest pain of nonischemic origin, 9 patients with unstable angina, 11 with stable angina, 11 patients with chronic muscular diseases, 6 patients with muscular trauma without chest contusion, and 13 patients with chronic renal disease. We found that: (a) 99% of the blood donors had TnI concentrations <0.26 microgram/L (detection limit of the assay in our study); (b) TnI values in acute myocardial infarction (AMI) patients 4 h after onset of chest pain showed a sensitivity of 0.769 and a specificity of 1.0 at a decisional concentration for AMI of 1 microgram/L, even in the presence of severe skeletal muscle injuries or renal diseases; (c) the increase in TnI concentrations after infarction (interquartile range 3.25-6 h) and the peak occurred later (interquartile range 11.5-24 h) than the rise found in myoglobin and CK-MB, but the increase persisted much longer (>96 h); (d) receiver-operating characteristic curve analysis showed the high diagnostic accuracy of TnI in diagnosing AMI even in patients in whom traditional biochemical markers are adversely influenced by underlying clinical situations.

Aged↗
PubMed1996

Receiver-operating characteristic (ROC) curves: a fundamental tool for improving the clinical usefulness of in vitro IgE tests.

In order to establish the most efficient thresholds for serum allergen-specific IgE measured by the Pharmacia CAP System, a "second-generation" in vitro method, we evaluated results from 89 subjects with suspected inhalant allergies, using receiver-operating characteristic (ROC) curve analysis. Sera samples were analyzed by the Pharmacia CAP System for specific IgE, the choice of allergens to be tested being based upon the symptoms and clinical history of each patient. Results were analyzed by ROC analysis for the five most representative allergens, cat dander (e1), Dermatophagoides pteronyssinus (d1), Lolium perenne (g5), wall pellitory (W19), and wormwood (w5). The areas under the ROC curves were found to be satisfactory, ranging from 0.931 (e1) to 0.974 (g5) when we excluded w5, which had a significantly smaller area (0.81). To establish the most efficient threshold for each allergen, we calculated the clinical sensitivity, specificity, efficiency, and negative and positive predictive values. The thresholds giving a higher diagnostic efficiency were as follows: 0.40 kUa/l for d1, 0.55 kUa/l for g5, 0.50 for e1, 0.65 kUa/l for w19, and 1.00 kUa/l for w5. It is concluded that quantitative reporting of specific IgE measurement has numerous advantages, but the choice of the positive threshold seems to be a prerequisite for obtaining the optimal clinical efficiency. It is also suggested that a specific threshold should be adopted for each allergen.

Adolescent↗
PubMed1996

Clinical evaluation of a new quantitative method for specific IgE antibodies.

We studied the analytical and clinical efficiency of a "second generation" technique for the in vitro determination of specific IgE, the so-called CARLA system (Capture Assay Radim Liquid Allergen). Reproducibility studies demonstrated satisfactory intra- and inter-assay analytical imprecision. The linearity test gave good results, and no significant interference by non-specific total IgE was found. The diagnostic efficiency of the system for the five most representative aeroallergens (D1, Dermatophagoides pteronyssinus; E1, Cat's epithelium; G5, Lolium perenne; W19, Parietaria officinalis and W5, Arthemisia absinthium) was evaluated using the Receiver Operating Characteristic (ROC) analysis in eighty-nine patients with suspected inhalant allergies. For each aeroallergen the area under the ROC curve and the most efficient threshold were calculated. Satisfactory areas under the ROC curve were found for D1, G5, E1 and W19, while a lower diagnostic efficiency was observed for W5. The most efficient thresholds differed from one allergen to another, although the differences were not great.

Adolescent↗
PubMed1996

Audit in laboratory medicine.

Laboratory medicine is at a crossroads that provides great opportunities to improve the efficacy of the service and its role in healthcare. Many of the new roles for laboratory staff will be outside the boundaries of the traditional laboratory. These roles include increased emphasis on consultative activities, participation in interdisciplinary teams, and efforts to assure appropriate test utilization. Audit in laboratory medicine may be defined as a process of review and assessment of laboratory performance, and its purpose should be to improve patient care by enhancing laboratory performance and making better use of resources. Here we discuss the rationale of audit in laboratory medicine, its goals as well as its topics. The suggested conduct for an audit and the involvement of personnel are also reviewed.

Laboratories↗
PubMed1996

Activation of cytotoxic and natural killer T-cell system in patients with hepatocellular carcinoma and cirrhosis.

The immune response in liver cirrhosis and hepatocellular carcinoma is receiving renewed attention in consideration of the possible treatment with biological response modifiers. The aim of this study was to evaluate whether cirrhosis and hepatocellular carcinoma induce any modification in peripheral lymphocyte subsets. Lymphocytes were evaluated (number/percentage) in 61 patients with hepatocellular carcinoma, 35 with cirrhosis and 24 healthy controls. Using flow cytometry, 10 lymphocyte subpopulations were assayed, plus the CD4/CD8 ratio. Results demonstrated no change in the number of lymphocytes; cirrhosis and hepatocellular carcinoma patients had significantly more HLA-DR+ (p = 0.001) and CD3+/HLA-DR+ (activated T) (p = 0.002) and fewer CD3+ (mature T) (p = 0.02) cell than controls; hepatocellular carcinoma patients had significantly more CD3+/CD56+/CD16- (cytotoxic non-MHC restricted T cells) and CD25+ (IL-2 receptor positive cells). If the percentages of all cells with cytotoxic-T activity were pooled, a significant increase (p = 0.03) was seen in hepatocellular carcinoma patients. In conclusion, in contrast to previous data, hepatocellular carcinoma patients reveal an increased number of cytotoxic non-MHC restricted T cells.

Antigens, CD↗
PubMed1995

Cysteine and serine proteases in gastric cancer.

BACKGROUND: Cysteine proteases (cathepsin B [CATB] and cathepsin L [CATL]), the serine protease urokinase-type plasminogen activator (UPA), and plasminogen activator inhibitor type-1 (PAI-1) are thought to play an important part in cancer invasion and metastasis. The aims of this study were to measure CATB, CATL, UPA, and PAI-1 in gastric cancer (GC) and normal mucosa distant from the tumor (NORM); to evaluate whether tissue levels are related to tumor stage, grade, or histotype; to assess their prognostic relevance; and to examine UPA and PAI-1 expression immunohistochemically. METHODS: Gastric cancer and NORM samples were obtained from 25 patients with gastric cancer patients undergoing surgery (17 males, 8 females; mean age, 62 years; range, 31-84 years). Antigen concentrations were measured using the enzyme-linked immunosorbent assay method. Immunohistochemistry was performed using monoclonal UPA and PAI-1 antibodies. RESULTS: Significantly higher antigen levels were found: (1) in GC vs. NORM (CATB, CATL, UPA, PAI-1) tissues; (2) in GC with versus without metastasis (CATB, CATL, UPA); (3) in poorly or moderately versus well differentiated GC; and (4) in diffuse versus intestinal-type GC (CATB, CATL). Urokinase-type plasminogen activator, PAI-1 and CATB levels had a significant prognostic impact. Cancer and stromal cells, showed immunoreactivity to anti-UPA and anti-PAI-1 antibodies. CONCLUSIONS: These results confirm the important role of CATB, CATL, UPA and PAI-1 in gastric cancer progression. Higher levels are detected in GC with metastases, poorer differentiation, and diffuse histotype, thus identifying patients with a worse prognosis.

Adenocarcinoma↗
PubMed1995

Quantitative cytochemistry of human leukocyte elastase compared with plasma elastase and acute phase proteins in inflammatory diseases.

Plasma levels of human leukocyte elastase, a serine proteinase stored in the azurophilic granules of polymorphonuclear granulocytes, increase in the early stages of several inflammatory diseases. We studied the intracellular enzyme activity by cytochemical quantitative image analysis and the amount of elastase released in plasma by an automatic immunoactivation immunoassay method in 66 patients with inflammatory diseases and in a control group. The patients were divided into two groups with infective disease (severe and moderate) and one group with non-infective inflammation. Intracellular activity and plasmatic levels of elastase were also compared with other inflammatory markers, i.e. erythrocyte sedimentation rate, C-reactive protein, alpha 1-antitrypsin, haptoglobin, alpha 1-acid glycoprotein and fibrinogen. Our studies suggest that plasma and leukocyte elastase are correlated both with etiology and with the severity of the inflammation.

Acute-Phase Proteins↗
PubMed1995

[Role and behavior of cathepsin B and cathepsin L in gastric cancer].

Cathepsin B and cathepsin L--cysteine proteinases--may play an important role in cancer invasion and metastasis. The authors determined tissue antigen concentrations of cathepsins, using the ELISA method, in 25 patients with gastric cancer (17 males, 8 females, mean age 62, range 31-84). They evaluated the possible relationship that these proteinases may have with the presence of metastases, differentiation and histotype. Significantly higher cathepsin B and cathepsin L antigen levels were found: 1. in gastric cancer tissues vs. normal tissues distant from tumors (CATB: p < 0.05, CATL: p < 0.005); 2. in diffuse vs. intestinal type cancers (p < 0.05); 3. in patients with poorly vs. well-differentiated cancers (p < 0.05); in gastric cancers with vs. without metastasis (p < 0.05). Their results confirm that cathepsin B and L play an important role in gastric cancer invasion and metastasis. Considering the significantly higher cathepsins detected in cancers with metastasis, a poor differentiation and of diffuse histotype, these proteinases could be useful for identification gastric cancer patients with a poor prognosis.

Adult↗
PubMed1995

Urinary gonadotropin peptide: collection of specimens and cutoff levels.

A low-molecular-weight form of human chorionic gonadotropin (hCG), urinary gonadotropin peptide (UGP), has been isolated from the urine of pregnant women and of patients with cancer, mainly of gynecological origin. The clinical value of UGP measurement in gynecological diseases is under investigation but a preliminary study is necessary in order to ascertain whether there is a circadian rhythm in UGP production, to clarify the best way to express the results, and to establish the cutoff and decisional values. In our work we demonstrated a significant correlation between the UGP output and the UGP excretion normalized for urinary creatinine. A very significant agreement was even found in 24-hr urine collections and UGP concentration of a single morning specimen from the same patients. No evident circadian rhythm was found, although some patients presented morning levels of UGP higher than in other collections. UGP postmenopausal levels were higher than premenopausal. The cutoff level, adopting the 95.0 percentile, was 200 pmol/mol creatinine.

Adolescent↗
PubMed1995

Evaluation of a new automated system for the determination of CK-MB isoforms.

We evaluated a new analyzer (Cardio REP) specifically designed for cardiac CK-MB isoenzyme and isoforms activity, with a performance time of 24 minutes. Ten AMI patients, with times elapsed between the onset of chest pain and admission to hospital ranging from 30 minutes to 4 hours, were monitored every 3-4 hours until the 16th hour of hospitalization. In each serum sample, in addition to total CK-MB and CK-MB isoforms measured by the Cardio REP analyzer, we also assayed total CK activity, CK-MB activity by immunoinhibition method, CK-MB mass concentration, CK-MB isoforms by REP method, troponin T, and myoglobin. The precision study demonstrated acceptable within assay and between assay CVs% for total CK-MB (8.1 and 10.4), MB1 (9.1 and 14.2), and MB2 (9.1 and 8.2) isoforms. The method was found to be linear up to 371 U/L for MB2 isoform fraction and up to 516 U/L for total CK-MB. Results for CK-MB obtained with the Cardio REP correlated well with those for CK-MB activity obtained with the immunoinhibition method (r = 0.869) and those of CK-MB mass concentration (r = 0.923). The sensitivity of the Cardio REP CK isoforms method was found to be greater than that of the REP CK isoforms method. Time to first increased value of MB2/MB1 ratio and MB2 isoform was earlier in comparison to that for CK-MB mass concentration and similar to that for myoglobin, a marker that, however, lacks specificity. The diagnostic efficiency of CK-MB isoforms and the availability of a real-time, fully automated method for their measurement suggest that utilization of this biochemical marker in emergency for the early diagnosis of AMI.

Blood Protein Electrophoresis↗