Showing papers by "University of Turin published in 1989"
University of Sheffield1, University of Warsaw2, Yale University3, CERN4, University of Liverpool5, Lancaster University6, University of Oxford7, Laboratoire d'Annecy-le-Vieux de physique des particules8, RWTH Aachen University9, University of Freiburg10, University of Turin11, Uppsala University12, Max Planck Society13
TL;DR: An investigation of the spin structure of the proton in deep inelastic scattering of polarised muons on polarised protons was performed in this article, where the spin was investigated in the context of the deep scattering process of polarized muons.
813 citations
TL;DR: The rapid haematological recovery made possible by this approach promises to increase the therapeutic index of high-dose chemoradiotherapy regimens and to widen their role as treatment for chemoradiosensitive tumours.
748 citations
TL;DR: It is reported that G-CSF and GM- CSF influence the migration and proliferation of human endothelial cells suggesting that these molecules may act as regulatory signals outside the haematopoietic system.
Abstract: Granulocyte-colony stimulating factor (G-CSF) and granulocyte-macrophage-colony stimulating factor (GM-CSF) belong to a family of glycoprotidic growth factors required for the survival, growth and differentiation of haematopoietic precursors and which affect the function of circulating mature cells. They are produced by resting or stimulated stromal cells of the haematopoietic microenvironment (fibroblasts and endothelium) and by immunocompetent cells (T cells and monocytes/macrophages). The action of these CSF molecules was thought to be restricted to cells of haematopoietic origin. Here, we report that G-CSF and GM-CSF influence the migration and proliferation of human endothelial cells suggesting that these molecules may act as regulatory signals outside the haematopoietic system.
627 citations
TL;DR: It is shown that p190 is indistinguishable from the protein encoded by the c-met protooncogene and that the αβ-subunit structure is conserved in other human cell lines, and the high level of p190 found in the GTL-16 cell line is accompanied by amplification and overexpression of c- Met.
Abstract: Growth factor receptors with protein tyrosine kinase activity are central to the control of proliferation of both normal and malignant cells. Using anti-phosphotyrosine antibodies, we have previously identified a transmembrane glycoprotein with abnormally high protein tyrosine kinase activity in a human gastric tumour cell line (GTL-16). Electrophoresis under non-reducing conditions revealed that this kinase (relative molecular mass 145,000 (145 K)) is disulphide-linked to a 50K chain in an alpha beta-complex of 190K (p190). From its novel two-chain structure, we deduced that p190 was the prototype of a new class of tyrosine kinase receptors. We now show that p190 is indistinguishable from the protein encoded by the c-met proto-oncogene and that the alpha beta-subunit structure is conserved in other human cell lines. We also show that the high level of p190 found in the GTL-16 cell line is accompanied by amplification and overexpression of c-met. This provides the first example of a functional alteration of c-met in a human tumour cell line.
485 citations
TL;DR: In this article, the surface characterization of silicalite and titanium-silicalite is made by combined use of IR and UV-Vis reflectance spectroscopy, and the nature of the IR modes and of the electronic transitions associated with framework titanium is discussed in detail.
Abstract: Surface characterization of silicalite and titanium-silicalite is made by combined use of IR and UV-Vis reflectance spectroscopy. The nature of the IR modes and of the electronic transitions associated with framework titanium is discussed in detail. The perturbation caused by the adsorption of small polar molecules (H 2 O, NH 3 , CH 3 OH) on both the IR and UV-Vis spectra is discussed in terms of the formation of six-coordinated complexes by ligand insertion in the Ti(IV) coordination sphere. All the Ti(IV) is accessible to the interaction with the molecules.
392 citations
TL;DR: In this paper, a large body of published data is presented on the viscosity of alloy liquids at compositions corresponding to elements, intermetallic compounds and eutectics.
300 citations
TL;DR: Petri nets in which random delays are associated with atomic transitions are defined in a comprehensive framework that contains most of the models already proposed in the literature and includes an execution policy based on the choice of the next transition to fire independently of the associated delay.
Abstract: Petri nets in which random delays are associated with atomic transitions are defined in a comprehensive framework that contains most of the models already proposed in the literature. To include generally distributed firing times into the model one must specify the way in which the next transition to fire is chosen, and how the model keeps track of its past history; this set of specifications is called an execution policy. A discussion is presented of the impact that different execution policies have on semantics of the mode, as well as the characteristics of the stochastic process associated with each of these policies. When the execution policy is completely specified by the transition with the minimum delay (race policy) and the firing distributions are of the phase type, an algorithm is provided that automatically converts the stochastic process into a continuous time homogeneous Markov chain. An execution policy based on the choice of the next transition to fire independently of the associated delay (preselection policy) is introduced, and its semantics is discussed together with possible implementation strategies. >
238 citations
TL;DR: The results suggest that chronic hepatitis B with anti‐HBe in serum differs from chronic hepatitis with HBeAg in both natural history and response to interferon, witheculiar features are the frequency of spontaneous remissions and a high frequency of reactivation after a response to Interferon.
233 citations
Journal Article•
TL;DR: The c-met protein has similar structure and biosynthesis in other human cell lines and the presence of N-linked oligosaccharides in both the precursor and the mature protein was shown by enzymatic de-glycosylation of the immunoprecipitated proteins.
Abstract: The proto-oncogene c-met encodes a transmembrane protein with structural features of a growth factor receptor. We have previously shown that the c-met protein (c-Met) is a heterodimer of two disulphide linked chains of 50 kd (alpha) and 145 kd (beta). In this work we have studied the biosynthesis of the c-met product in a gastric carcinoma cell line (GTL-16) where the c-met gene is amplified and overexpressed. Following metabolic labelling of the cells in the presence of tunicamycin, anti-met antibodies immunoprecipitate a protein of 150 kd. In pulse-chase experiments carried out in the absence of tunicamycin, a 170 kd product appears first. Within the next few minutes, this precursor modifies its SDS migration, probably as a consequence of modification(s) of its intra-chain disulphide bonds. After 45 min of chase, this single polypeptide precursor is cleaved to form a 50 kd alpha subunit and a 145 kd beta subunit that are joined by disulphide bonds in an alpha beta complex with an apparent molecular weight of 190 kd. The presence of N-linked oligosaccharides in both the precursor and the mature protein was shown by enzymatic de-glycosylation of the immunoprecipitated proteins. The half-life of the mature protein was calculated to be approximately 5h. The c-met protein has similar structure and biosynthesis in other human cell lines.
228 citations
TL;DR: Eighty-five "well-differentiated" astrocytomas in adults, operated on between 1950 and 1982, were retrospectively reviewed and a score was developed to detect subgroups with different prognoses.
Abstract: Eighty-five "well-differentiated" astrocytomas in adults (age, greater than or equal to 18 years), operated on between 1950 and 1982, were retrospectively reviewed. The pilocytic variant was not included. Twenty-four clinical and 8 histological factors were analyzed to investigate their importance in predicting length of survival. Multivariate analysis showed that the following variables were correlated with survival time (P less than 0.01): extent of surgical removal, altered consciousness during preoperative examination, focal deficit as presenting symptom, performance status (Karnofsky rating) after surgery, and vessel size in the surgical specimen. Total removal of the tumor was related to a higher 5-year survival rate (51%) than subtotal removal (23.5%), and none of the patients with partial removal survived more than 5 years. Postoperative radiotherapy (40-55 Gy) improved only the 1- and 3-year survival rates. Based on the significant factors provided by multivariate analysis, a score was developed to detect subgroups with different prognoses. Median survival time ranged from 383 days for patients with a score greater than or equal to 2.5 to 1,533 days for those with a score less than 0.5; no patient with a score greater than or equal to 1.5 survived more than 10 years. The percentage of recurring astrocytomas that showed anaplastic areas in the second biopsy specimen was 79%. Total surgical removal is the most important factor in the management of well-differentiated astrocytomas, whereas the efficacy of postoperative radiotherapy still needs to be confirmed by prospective and randomized studies. The rationale for treating incompletely resected astrocytomas with radiation therapy could lie in the high incidence of malignant transformation.
216 citations
TL;DR: Results indicate that OCLs produce an integrin complex that is absent in the monocyte-macrophage lineage.
Journal Article•
TL;DR: A positive association between oral cancer and low educational level, after adjustment for alcohol and tobacco, was found.
Abstract: A population-based case-control study of cancer of oral cavity-oropharynx was conducted in the city of Torino, Italy, between 1982 and 1984. One hundred twenty-two cases (86 males and 36 females) and 606 controls (385 males and 221 females) were compared with respect to lifelong alcohol and tobacco consumption. A 4- to 6-fold increase in risk among subjects with medium or high tobacco consumption was observed, as well as a trend in increasing risk with duration and with earlier age at the start of smoking. Other findings included a sharp reduction in risk with cessation of smoking, no clear protective effect of usage of filter, no differences in risk according to color of tobacco, and a higher risk for cigar versus pipe/cigarette smokers. An effect of alcoholic beverages was found in subjects with an average daily consumption of 120 or more grams of alcohol, with a higher risk in beer drinkers. Among heavy consumers of alcohol and tobacco, risks of both oral and oropharyngeal cancer were very high. A positive association between oral cancer and low educational level, after adjustment for alcohol and tobacco, was found. Attributable risks for alcohol and tobacco in the population were 23% and 72% in men and 34% and 54% in women.
TL;DR: It is concluded that in MM the malignant plasma cell precursors are circulating and their growth and terminal differentiation are under the synergistic control of IL-3 and IL-6.
Abstract: PBMC from 11 patients with multiple myeloma (MM) were cultured in vitro in presence of IL-3 and IL-6. After 3 d, actively proliferating immunoblast-like B cells (20-62%) were apparent. After 6 d, a population of morphologically evident plasma cells was observed (30-50%) that expressed, in each individual case, the same light and heavy chain produced by bone marrow malignant plasma cells. We conclude that in MM the malignant plasma cell precursors are circulating and their growth and terminal differentiation are under the synergistic control of IL-3 and IL-6.
TL;DR: The analysis of a consecutive series of 100 cases of breast cancer indicates that about 8% of breast carcinomas display some degree of NE differentiation, while the most frequent types of endocrine tumors (types A and C) have an intermediate grade of malignancy.
TL;DR: Serum IgG, pepsinogen I, and gastrin levels were significantly decreased after treatment and increases or decreases in IgG level indicated clearance or recurrence, respectively, of C pylori.
TL;DR: The first measurements of the mass and width of the Z 0 at the DELPHI Collaboration at the LEP Collider were presented in this article, where the authors derived the measurements from the multihadronic final states produced in e + e − annihilations at several energies around the 0 mass.
TL;DR: It is concluded that cG MP inhibits ICa in guinea pig ventricular cells by a mechanism different from the activation of a cGMP-stimulated phosphodiesterase recently found in frog ventricular Cells.
Abstract: The effect of intracellular perfusion with cyclic GMP (cGMP) on Ca current (ICa) was investigated in Cs-loaded isolated cells from guinea pig ventricle using the whole-cell patch-clamp technique and a perfused patch pipette. cGMP (5 μM) strongly reduced ICa which had been elevated by intracellular perfusion with 50 μM of either cyclic AMP (cAMP) or its hydrolysis-resistant analog 8-Bromo-cAMP. In addition, cGMP prevented the stimulation of ICa by IBMX, a phosphodiesterase inhibitor. The membrane permeant cGMP analog 8-Bromo-cGMP (100 μM), when applied outside the cell, also antagonized the stimulatory effect of IBMX on ICa. It is concluded that cGMP inhibits ICa in guinea pig ventricular cells by a mechanism different from the activation of a cGMP-stimulated phosphodiesterase recently found in frog ventricular cells.
TL;DR: The kinetic changes induced by granulocyte-macrophage colony-stimulating factor on hemopoietic cells were assessed in physiological conditions, suggesting that GM-CSF activates both erythroid and granulomonopOietic progenitors but that, among the morphologically recognizable BM precursors, only the granULomonopoetic lineage is a direct target of the molecule.
Abstract: The kinetic changes induced by granulocyte-macrophage colony-stimulating factor (GM-CSF) on hemopoietic cells were assessed in physiological conditions by administering GM-CSF (8 micrograms/kg per d) for 3 d to nine patients with solid tumors and normal bone marrow (BM), before chemotherapy. GM-CSF increased the number of circulating granulocytes and monocytes; platelets, erythrocytes, lymphocyte number, and subsets were unmodified. GM-CSF increased the percentage of BM S phase BFU-E (from 32 +/- 7 to 79 +/- 16%), day 14 colony-forming unit granulocyte-macrophage (CFU-GM) (from 43 +/- 20 to 82 +/- 11%) and day 7 CFU-GM (from 41 +/- 14 to 56 +/- 20%). The percentage of BM myeloblasts, promyelocytes, and myelocytes in S phase increased from 26 +/- 14 to 41 +/- 6%, and that of erythroblasts increased from 25 +/- 12 to 30 +/- 12%. This suggests that GM-CSF activates both erythroid and granulomonopoietic progenitors but that, among the morphologically recognizable BM precursors, only the granulomonopoietic lineage is a direct target of the molecule. GM-CSF increased the birth rate of cycling cells from 1.3 to 3.4 cells %/h and decreased the duration of the S phase from 14.3 to 9.1 h and the cell cycle time from 86 to 26 h. After treatment discontinuation, the number of circulating granulocytes and monocytes rapidly fell. The proportion of S phase BM cells dropped to values lower than pretreatment levels, suggesting a period of relative refractoriness to cell cycle-active antineoplastic agents.
Proceedings Article•
20 Aug 1989TL;DR: A formal theory of causal diagnostic reasoning is proposed, dealing with different forms of incompleteness both in the general causal knowledge (missing or abstracted knowledge) and in the data describing a specific case under examination.
Abstract: One of the problems of the recent approaches to problem solving based on deep knowledge is the lack of a formal treatment of incomplete knowledge. However, dealing with incomplete models is fundamental to many real-world domains. In this paper we propose a formal theory of causal diagnostic reasoning, dealing with different forms of incompleteness both in the general causal knowledge (missing or abstracted knowledge) and in the data describing a specific case under examination. Different forms of nonmonotonic reasoning (hypothetical and circumscriptive reasoning) are used in order to draw and confirm conclusions from incomplete knowledge. Multiple fault solutions are treated in a natural way and parsimony criteria arc used to rank alternative solutions.
TL;DR: Evidence showed that the trichome number was not fixed at the time of leaf emergence and a striking monoterpene composition variability was present among individual trichomes and between different parts of the leaf.
Abstract: The trichome number and the variability in mono and sequisterpene distribution of peltate trichomes within a leaf was investigated during development of peppermint (Mentha×piperita L.) leaves. A larger number of peltate trichomes was initiated on adaxial epidermises than abaxial epidermises, but during leaf development a greater gland number was produced on abaxial epidermises. Evidence showed that the trichome number was not fixed at the time of leaf emergence. On both epidermises, the trichome distribution was found to change with its position on the leaf. A striking monoterpene composition variability was present among individual trichomes and between different parts of the leaf. Different rates of peltate trichome development and distribution as well as significant differences in trichome number and density were found between the epidermises. A clear and opposite trend was found between menthone and menthol percentages during development. Menthone and menthol were also found to be present in larger amounts on adaxial epidermises, whereas neomenthol and isomenthol had highest percentages on abaxial epidermises. Of the total oil collected from peltate trichomes, 60%, was composed of menthone. isomenthol, menthol and neomenthol and of the remaining 40 %, more than half was represented by other mono and sesquiterpenes while the final percentage was made up of a few unidentified early eluting compounds of high Volatility.
TL;DR: In this paper, the elasticity moduli of the wave modulating films using a recently developed theory were analyzed to characterize the visco-elastic properties of the wind wave spectra.
Abstract: Organic sea surface films are often indicators of surface and subsurface processes that influence their formation and their spatial and temporal distribution. The films modify the physics of the sea surface and influence remotely sensed optical and microwave imagery. Natural sea surface films have been detected, charted, and characterized by measurements of the short-gravity spectra of wind waves during three experimental periods, one in the Sicilian Channel, and two in the Gulf of Maine. Wind wave spectra with and without organic films were measured in situ with a microwave probe. These spectra were analyzed to characterize the elasticity moduli of the wave modulating films using a recently developed theory. Theory and experiment are in good agreement. It has been demonstrated that the microwave probe can detect the presence of sea surface films and their visco-elastic properties by the measurement of their wave-modulating effects. The data collected by this system can possibly be further interp...
TL;DR: In this paper, Hartree-Fock calculations of the (0001) and (1010) crystal faces of α-alumina have been performed using a slab model and taking full account of two-dimensional periodicity.
TL;DR: The data indicate that both a functional inhibition of IFN-gamma and its continuous presence at high levels may result in hyporesponsiveness or unresponsiveness of immune cells.
TL;DR: Les deplacements chimiques, les largeurs des bandes en RMN and les bandes d'absorption IR permettent de caracteriser les catalyseurs heteropolyacides supportes sur silice et/ou alumine as mentioned in this paper.
TL;DR: It is shown that even a strong violation of the equivalence principle could becompatible with the experimental data, provided the gravity-induced energysplitting is balanced by a suitable neutrino mass difference.
Abstract: The negative results of the oscillations experiments are discussed with thehypothesis that the various neutrino types are not universally coupled togravity. In this case the transition probabiltiy between two different flavoreigenstates may be affected by the local gravitational field present in aterrestrial laboratory, and the contribution of gravity can interfere, ingeneral, with the mass contribution to the oscillation process. In particularit is shown that even a strong violation of the equivalence principle could becompatible with the experimental data, provided the gravity-induced energysplitting is balanced by a suitable neutrino mass difference.
TL;DR: Measurement of IgG antibody levels, combined with serum pepsinogen I estimation, predict the presence of C pylori associated gastritis in children with a sensitivity and specificity of up to 95%.
Abstract: A consecutive series of 51 children (mean age 11 years) who presented with recurrent abdominal pain were investigated by upper gastrointestinal endoscopy including three antral biopsies for microscopy, culture and urease testing. Serum IgG, IgA, and IgM antibodies to Campylobacter pylori (C pylori) were measured by the ELISA technique. Serum pepsinogen I was also measured. Thirty two children showed histological evidence of gastritis. All had C pylori on microscopy and or culture. Nineteen children showed no histological gastritis nor evidence of C pylori on microscopy, culture and/or urease testing. The IgG and IgA antibody levels to C pylori were significantly higher in C pylori positive children than in the negative group (p less than 0.001). Serum pepsinogen I concentrations were also significantly higher in C pylori positive children than in negative (p less than 0.001). Measurement of IgG antibody levels, combined with serum pepsinogen I estimation, predict the presence of C pylori associated gastritis in children with a sensitivity and specificity of up to 95%. It may be used therefore to predict gastritis and even peptic ulceration in children presenting with non-specific upper abdominal pain.
TL;DR: In this paper, the integrated CCR (canonical commutation relations) for 2+1 dimensional gravity in the vielbein first order formalism are used to derive generalised representations Ψ: π1 (Σ) → ISO(2, 1) of the fundamental group of the initial data surface Σ2.
TL;DR: Computer assisted analysis shows that gp42 is distinct from previously characterized proteins, but shares a number of structural features with the class II histocompatibility antigens, and is a new member of the Ig superfamily.
TL;DR: The results of thymectomy in the treatment of myasthenia gravis (MG) are reviewed in the light of a personal series of 662 patients, operated upon during the last 15 years, and no correlations are found between outcome and thymic histology.
Abstract: The purpose of this paper is to evaluate the results of thymectomy in MG and to analyse whether its effects are influenced by the following factors: age and sex of the patients, duration and severity of the disease, thymic histology or invasive tumour, and to discuss the problem of the surgical approach