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C Pellegrini

Publications and source records attributed to C Pellegrini.

At least 91 records · Page 5Linked to original sources
PubMed1991

LaboImage: a workstation environment for research in image processing and analysis.

Numerous images are produced daily in biomedical research. In order to extract relevant and useful results, various processing and analysis steps are mandatory. The present paper describes a new, powerful and user-friendly image analysis system: LaboImage. In addition to standard image processing modules. LaboImage also contains various specialized tools. These multiple processing modules and tools are first introduced. A one-dimensional gel analysis method is then described. The new concept of 'normalized virtual one-dimensional gel' is introduced, making comparisons between gels particularly easy. This normalized gel is obtained by compensating for the bending of the lanes automatically; no information loss is incurred in the process. Finally, the model of interaction in a multi-window environment is discussed. LaboImage is designed to run in two ways: interactively, using menus and panels; and in batch mode by means of user-defined macros. Examples are given to illustrate the potentialities of the software.

Algorithms↗
PubMed1990

From biopsy to automatic diagnosis.

High resolution two-dimensional gel electrophoresis is a very powerful biochemical tool for analysis of complex protein mixtures. In well defined situations, protein maps, obtained from tissue biopsies or biological fluids by this technique, can be automatically analyzed by computer. Some polypeptide patterns are the fingerprints of diseases. Applying clustering algorithm and learning techniques, the prototype expert system MELANIE recognized patterns and associated the correct diagnosis to the specific pattern.

Diagnosis, Computer-Assisted↗
PubMed1988

Automatic classification of two-dimensional gel electrophoresis pictures by heuristic clustering analysis: a step toward machine learning.

The interpretation of two-dimensional gel electrophoresis (2-DGE) profiles can be facilitated by artificial intelligence and machine learning programs. We have incorporated into our 2-DGE computer analysis system (termed MELANIE-Medical Electrophoresis Analysis Interactive Expert system) a program which automatically classifies 2-DGE patterns using heuristic clustering analysis. This program is a step toward machine learning. In this publication, we describe the classification method and the preliminary results obtained with liver biopsy electrophoretograms. Heuristic clustering is also compared to other classification techniques.

Algorithms↗
PubMed1988

"High-resolution" mini-two-dimensional gel electrophoresis automatically run and stained in less than 6 h with small, ready-to-use slab gels.

Although two-dimensional (2-D) gel electrophoresis is one of the most powerful techniques for analyzing protein mixtures, its application in routine clinical laboratories is currently limited, because it is time-consuming, complex, and relatively expensive. Here we describe a method for automatically running and staining "high-resolution" mini 2-D electrophoresis gels in less than 6 h, by using "ready-to-use" slab gels and a PhastSystem electrophoresis apparatus. We present 2-D gel electrophoretograms of 25 nL of plasma, as well as their automatic computer analysis. For comparison, a conventional 2-D gel electrophoresis profile of 200 nL of a plasma sample is shown. The technique is easy to perform, highly sensitive, rapid, and potentially useful in semi-routine clinical chemistry laboratories.

Autoanalysis↗
PubMed1988

Protein heterogeneity of lipoprotein particles containing apolipoprotein A-I without apolipoprotein A-II and apolipoprotein A-I with apolipoprotein A-II isolated from human plasma.

The protein heterogeneity of fractions isolated by immunoaffinity chromatography on anti-apolipoprotein A-I and anti-apolipoprotein A-II affinity columns was analyzed by high resolution two-dimensional gel electrophoresis. The two-dimensional gel electrophoresis profiles of the fractions were analyzed and automatically compared by the computer system MELANIE. Fractions containing apolipoproteins A-I + A-II and only A-I as the major protein components have been isolated from plasma and from high density lipoproteins prepared by ultracentrifugation. Similarities between the profiles of the fractions, as indicated by two-dimensional gel electrophoresis, suggested that those derived from plasma were equivalent to those from high density lipoproteins (HDL), which are particulate in nature. The established apolipoproteins (A-I, A-II, A-IV, C, D, and E) were visible and enriched in fractions from both plasma and HDL. However, plasma-derived fractions showed a much greater degree of protein heterogeneity due largely to enrichment in bands corresponding to six additional proteins. They were present in trace amounts in fractions isolated from HDL and certain of the proteins were visible in two-dimensional gel electrophoresis profiles of the plasma. These proteins are considered to be specifically associated with the immunoaffinity-isolated particles. They have been characterized in terms of Mr and pI. Computer-assisted measurements of protein spot-staining intensities suggest an asymmetric distribution of the proteins (as well as the established apolipoproteins), with four showing greater prominence in particles containing apolipoprotein A-I but no apolipoprotein A-II.

Apolipoprotein A-I↗
PubMed1988

Computerized classification of two-dimensional gel electrophoretograms by correspondence analysis and ascendant hierarchical clustering.

A powerful data processing methodology for analysis and classification of two-dimensional gels is introduced. The approach is based on correspondence analysis (CA) and ascendant hierarchical classification (AHC), and significantly differs from the more classical principal-component decomposition. Starting with a series of gels, each having a large number of spots, CA allows their representation in a factorial space of reduced dimension; classification into meaningful groups is then performed using AHC. Simultaneous representation of both spots and gels in the same space can be done. This precisely indicates the key spots pertinent for the classification, and therefore the characteristic proteins representative of a particular class of gels (i.e. of a particular disease or biological status). In addition, knowledge of these characteristic spots greatly simplifies the screening of future gels. After a brief overview of the Mélanie system for analyzing 2D gels, the theory of correspondence analysis and ascendant hierarchical classification is summarized. Equations are given that are easily ammenable to computation. How classification of two-dimensional gel electrophoretograms is accomplished is then detailed. Experimental results support the power of this approach.

Cluster Analysis↗
PubMed1987

Personality and duodenal ulcer response to antisecretory treatment.

Two groups of duodenal ulcer (DU) patients, responders and nonresponders, have been compared in order to verify if psychological factors are linked to relapse. Responders are defined as those patients who on endoscopy did not present proven relapse during treatment with maintenance doses of antisecretory drugs (cimetidine 400 mg/day, ranitidine 150 mg/day, pirenzepine 50 mg/day) for a period of 12 months after healing of the lesion. Nonresponders were all patients presenting with at least one relapse during treatment with antisecretory drugs. One hundred and twelve DU patients (81 responders, 31 nonresponders) were examined with the Cattell 16 Personality Factors Questionnaire (16PF) form C. There were no significant differences between the two groups for age, sex, duration of illness and type of drug treatment. The 16 PF scores of responders and nonresponders were not statistically different except in the case of factor E (dominance), in which the nonresponder subjects scored higher than responder subjects (p less than 0.01). However, when the significance level was corrected for the number of variables involved, the above finding is not considered to be meaningful.

Cimetidine↗
PubMed1987

Outcome from carotid endarterectomy. Neuropsychological performances, depressive symptoms and quality of life: 8-month follow-up.

A preliminary study was carried out on a population of twenty-five consecutive and unselected patients undergoing carotid endarterectomy. A matched control group of subjects suffering from same pathology, but unoperated, was compared to experimental sample. A battery of neuropsychological tests, the Zung Self-Rating Depression Scale and the Jachuck's Quality of Life Impairment Scale were administered one week before surgery, two weeks after (surgical sample only) and then eight months later. The research shows that carotid endarterectomy does not impair neuropsychological performances, but produces some improvement, reaching significant level in the case of Word Fluency 1 and Similarities tests; depressive scores remained substantially unchanged, while quality of life improved slightly.

Aged↗
PubMed1986

[Protein mapping of normal circulating cells: lymphocytes and monocytes].

Purified lymphocyte and monocyte populations were obtained from peripheral blood cells by ficoll-hypaque gradient and elutriation in different normal individuals. The two types of mononuclear cells were then analyzed by 2-dimensional gel electrophoresis. More than 1,000 spots were detected by our computer system and analyzed for each cell type. Automatic picture comparison showed a typical pattern for the two different populations with excellent reproducibility.

Blood Protein Electrophoresis↗
PubMed1986

Assessment of severity of suicide attempts. A trial with the dexamethasone suppression test and 2 rating scales.

In this study, the dexamethasone suppression test (DST) and 2 rating scales, the 'Echelle d'Evaluation de Risque Suicidaire' and the Pierce modified form of the Suicide Intent Scale, were administered to a group of 37 subjects admitted to the general hospital of Padua for suicide attempts. The purpose of our study was to verify if these tools could be considered useful in assessing the severity of the attempts. 10 subjects were DST-positive, but the test evidenced very low sensitivity and predictive value. The 2 rating scales demonstrated a good degree of concordance in identifying the adjustment disorder group as being at a lower risk for a serious attempt.

Adult↗
PubMed1985

Intraoperative sonography of perisplenic pseudocysts.

Three patients with pseudocysts of the pancreas affecting the spleen were examined with intraoperative sonography, which demarcated the fluid collections either within the pancreas (two cases), in the splenic hilum (one case), encapsulating the spleen (one case), or along the lateral aspect of the spleen (one case). This method was useful in defining the location of the cysts, distinguishing one from another, determining the relation of the cyst to adjacent organs, and assessing the adequacy of the surgical drainage.

Adult↗
PubMed1984

Variations in concentrating function of the gallbladder in the conscious monkey.

Hepatic bile is concentrated in the gallbladder by absorption of water and electrolytes. The rate of water absorption can be influenced in vitro and in vivo by gastrointestinal hormones and neurogenic transmitters. Recent studies have demonstrated that besides its absorbing activity, the gallbladder has the ability to secrete fluid into its lumen. In the present experiments, we studied the rate of net water absorption in the gallbladders of pig-tailed monkeys sitting in restraining chairs. Bile from the common bile duct and the gallbladder was led out through cannulas to a stream splitter, samples were obtained, and bile was returned to the duodenum. By measuring outflow from the gallbladder and the concentration of bile acids in hepatic bile and bile that had passed through the gallbladder, net water absorption from the gallbladder bile could be calculated. The results demonstrate that during daytime fasting there was a net absorption corresponding to 30% of the fasting gallbladder volume per hour, and after feeding there was a net secretion of fluid into the gallbladder lumen. Compared with the awake fasting state, net water absorption from the gallbladder decreased at night while the animal was fasting and asleep. Physiologically, secretion of fluid after a meal could help to empty the gallbladder, and changes in net water absorption by the gallbladder could influence the kinetics of the enterohepatic circulation of bile acids.

Absorption↗
PubMed1981

The effect of splenectomy on the appearance of specific antibody-forming cells in lungs of dogs after intravenous immunization with sheep erythrocytes.

Effector cells of both T-lymphocyte-mediated and B-lymphocyte-mediated immunity can be induced experimentally to appear in the lung. It is not known whether such effector lymphocytes arise from precursor cells resident in the lung or if they are recruited from systemic sources. Previous studies demonstrated that IV administration of sheep erythrocytes to dogs consistently resulted in the appearance of specific antibody-forming cells, B-cell effectors, in lavage preparations obtained from the lung. In the present study, experiments were performed to determine the mechanism of appearance of effector B-cells in the lung after IV immunization. Control, sham-operated, and splenectomized dogs were immunized IV with 10(10) sheep erythrocytes. The concentrations of antibody-forming cells appearing in lymphocytes obtained from the lung and from peripheral blood were measured during both the primary and the secondary immune responses. Control and sham-operated dogs developed high concentrations of antibody-forming cells in blood 5 days after immunization, but splenectomized dogs did not. Antibody-forming cells consistently appeared in substantial numbers in lymphocytes obtained by lavage from lungs of control and sham-operated animals, however, they failed to appear in lungs of animals which had undergone splenectomy. Similar results were obtained both after primary and after secondary IV immunization. The data indicate that in this model, namely after IV immunization, with sheep erythrocytes, pulmonary antibody-forming cells or their precursors are derived from systemic sources (spleen) via the circulating blood. The observations provide strong in vivo evidence that lung antibody-forming cells are not generated locally after IV priming and boosting. The results of the present study relate directly to the mechanism of appearance of antibody-forming cells in lungs after IV, not local immunization. The study defines and documents one mechanism by which immune effector cells can appear in lung tissue.

Animals↗