Showing papers by "University of Turin published in 1988"

A family of human CCAAT-box-binding proteins active in transcription and DNA replication: cloning and expression of multiple cDNAs

Abstract: The CTF/NF-I group of cellular DNA binding proteins recognizes the sequence GCCAAT and is implicated in eukaryotic transcription as well as DNA replication. Molecular analysis of human CTF/NF-I complementary DNA clones reveals multiple messenger RNA species containing alternative coding regions, apparently as a result of differential splicing. Expression and functional analysis establish that individual gene products can bind to GCCAAT recognition sites and serve both as promoter-selective transcriptional activators and as initiation factors for DNA replication.

Cancer of the larynx/hypopharynx, tobacco and alcohol: IARC international case-control study in Turin and Varese (Italy), Zaragoza and Navarra (Spain), Geneva (Switzerland) and Calvados (France).

Abstract: A case-control study on larynx and hypopharynx cancer was carried out in 6 populations including the city of Turin and the province of Varese (Italy), the provinces of Navarra and Zaragoza (Spain), the canton of Geneva (Switzerland), and the departement of Calvados (France). This report presents an analysis of the risk associated with alcohol and tobacco consumption based on 1,147 male cases and 3,057 male population controls. Special attention was given to the study of the risk at various sites of larynx and hypopharynx. The effect of tobacco is similar for all sites and the risk associated with ever smoking is on the order of 10. The risks from alcohol drinking depend on site. They are similar for epilarynx and hypopharynx (RR = 4.3, for more than 80 g/day) and lower for endolarynx (RR = 2.1, for more than 80 g/day). For all sites the risk decreases after quitting (RR = 0.3 after 10 years); exclusive use of filter cigarettes is protective (RR = 0.5 relative to smokers of plain cigarettes only) as is exclusive use of blond tobacco (RR = 0.5 relative to smokers of black tobacco only). Inhalation increases the risk of endolaryngeal cancer but not that of hypopharynx or epilarynx. The relative risks for joint exposure to alcohol and tobacco are consistent with a multiplicative model.

Selective growth response to IL‐3 of a human leukaemic cell line with megakaryoblastic features

Abstract: A new human leukaemic cell line (M-O7) with the phenotypic characteristics of CFU-mega is described. Its cells are positive for T200 leucocyte common antigen (LCA) and negative with MAbs recognizing T and B cells and mature myelomonocytic antigens. In contrast, they react with MAbs recognizing antigenic determinants common to multi-lineage (CD13, CD33, CD34) and to bipotent erythromegakaryoblastic (CD36, H25) haemopoietic precursors, and with MAbs specific for platelet glycoproteins (CD41w, CD42w). A small proportion (10%) of the cells were large and multinucleated, and on electron-microscopy examination showed peripheral splitting of platelet-like cytoplasm particles. When transferred to a serum-free Iscove modified Dulbecco's medium supplemented with human insulin and transferrin, M-O7 cells stop proliferating. Of the haemopoietic growth factors tested for their ability to restore the proliferative activity of this quiescent population, only rH IL-3 proved effective. Moreover, it also increased the cloning efficiency in methylcellulose more than any other CSFs. The M-O7 cell line may provide a valuable tool for the biological assay of IL-3, and a model for biochemical studies of the megakaryocytic lineage.

Photocatalytic degradation of phenol in aqueous titanium dioxide dispersions

Abstract: The results of a study of photocatalytic degradation of phenol using aqueous oxygenated TiO2 (anatase) suspensions in a batch Pyrex photoreactor are reported The influence on the photodegradation rate of various parameters as pH, phenol and TiO2 content, oxygen partial pressure, anions present in the dispersions was investigated A complete oxidation of phenol was observed Intermediate compounds, catechol and quinone, were detected It was observed that the photodegradation also proceeded with sunlight radiation A mechanistic and kinetic model, which accounts for the results obtained, is given Likely reasons for inactivity of the rutile modification for this reaction are also given

A genetic history of Italy.

Abstract: Statistical techniques for displaying the geographical distribution of many genes in few synthetic images have been used to represent the various patterns of gene frequencies in Europe and in the world (Menozzi et al. 1978; Piazza et al. 1981 a). It has also been shown that such synthetic displays are particularly useful in detecting clines of genetic differentiation associated with movements of populations like those accompanying the Neolithic expansion of farmers from the Near East or, in more recent times, the putative diffusion of Indo-European-speaking populations (Ammerman & Cavalli-Sforza, 1984; Gimbutas, 1973). In this paper we use the same combination of statistical and graphical techniques to study the genetic structure of Italy, a European country whose unity of people and cultures was quite a recent event. The possibility of studying genetic differentiation in a small geographical area is tested and trends of genetic differences are tentatively interpreted in terms of historic and linguistic knowledge. The few demographic pieces of information taken from historical sources and compared with linguistic records support the hypothesis that the genetic structure of Italy still reflects the ethnic stratification of pre-Roman times.

Treatment of recurrent squamous cell carcinoma of the head and neck with low doses of lnterleukin‐2 injected periiymphatically

Abstract: Ten patients with recurrent squamous cell carcinoma of the head and neck received daily injections of interleukin-2 (IL-2) from the Jurkat T-cell line purified by high pressure liquid chromatography for 10 days. Two hundred units of IL-2 in 0.5 ml were injected 1.5 cm from the insertion of the sternocleidomastoid muscle on the mastoid. When possible, courses were repeated at 45-day intervals. IL-2 was ineffective in two patients who had already undergone functional or radical neck dissection. By contrast, in six patients with contralateral or bilateral cervical lymph nodes, complete or partial disappearance of the tumor was observed. The injections were occasionally followed by moderate local swelling and lymph node pain, but no systemic disturbances.

Cell-wall-bound peroxidase activity in roots of mycorrhizal Allium porrum

Abstract: summary The activity of cell-wall-bound peroxidase in Allium porrum L. roots was measured during root growth and development of vesicular–arbuscular mycorrhiza with Glomus versiforme (Karst.) Berch. The peak of activity in infected plants was higher than in non-infected ones and occurred during the initial stages of fungal penetration. When the infection was established and the roots highly colonized the activity decreased to the levels in non-mycorrhizal roots. Ultrastructural localization using diaminobenzidine revealed an increase in the electron-dense deposits in the middle lamella corresponding with fungal penetration. No activity was seen in the matrix deposited around the intracellular fungal structures. The overall distribution of peroxidase activity was the same in mycorrhizal and non-mycorrhizal roots.

Specific demonstration of myoepithelial cells by anti-alpha smooth muscle actin antibody.

Abstract: The myoepithelial cells of the sweat, mammary, tracheobronchial, and salivary glands are specifically identified by monoclonal antibody alpha-SM-1, which recognizes alpha smooth muscle actin and not the other actin isoforms. Basal or "reserve" cells in the stratified epithelia and excretory ducts of the salivary glands are negative, as well as all other epithelial cells in various organs. The reaction can be performed in routinely fixed and embedded tissues and is of practical interest in diagnostic histopathology. In immunoelectron cytochemistry, alpha-SM-1 antibody binds to the microfilament bundles in myoepithelial cells of the breast, but does not stain luminal cells and occasional basally located epithelial cells. These basal cells are morphologically and immunocytochemically distinct from the myoepithelial cells, and their nature and significance remain to be clarified.

Riemannian Metrics on Tangent Bundles

Abstract: Some «natural» metrics on the tangent and on the sphere tangent bundle of Riemannian manifold are constructed and studied via the moving frame method.

Algebraic Riccati equations with non-smoothing observation arising in hyperbolic and Euler-Bernoulli boundary control problems

Abstract: This paper considers the optimal quadratic cost problem (regulator problem) for a class of abstract differential equations with unbounded operators which, under the same unified framework, model in particular «concrete» boundary control problems for partial differential equations defined on a bounded open domain of any dimension, including: second order hyperbolic scalar equations with control in the Dirichlet or in the Neumann boundary conditions; first order hyperbolic systems with boundary control; and Euler-Bernoulli (plate) equations with (for instance) control(s) in the Dirichlet and/or Neumann boundary conditions. The observation operator in the quadratic cost functional is assumed to be non-smoothing (in particular, it may be the identity operator), a case which introduces technical difficulties due to the low regularity of the solutions. The paper studies existence and uniqueness of the resulting algebraic (operator) Riccati equation, as well as the relationship between exact controllability and the property that the Riccati operator be an isomorphism, a distinctive feature of the dynamics in question (emphatically not true for, say, parabolic boundary control problems). This isomorphism allows one to introduce a «dual» Riccati equation, corresponding to a «dual» optimal control problem. Properties between the original and the «dual» problem are also investigated.

Insulin directly reduces platelet sensitivity to aggregating agents. Studies in vitro and in vivo.

Abstract: The aim of this study was to investigate the influence of insulin on platelet function, both in vitro and in vivo. For the in vitro investigation, we evaluated whether insulin affects platelet function at a physiological hormone concentration by incubating the platelet-rich plasma (PRP) of fasting subjects with human regular insulin at the final concentration of 40 μU/ml for 30 min; we observed a significant reduction of platelet sensitivity to all the aggregating agents employed, i.e., ADP, platelet-activating factor (PAF), epinephrine, collagen, and Na + arachidonate. To investigate whether the insulin effect on platelets is dose dependent, we incubated the PRP of fasting subjects with different concentrations of human regular insulin (40, 80, 120, and 160 μU/ml) for 5 min, and we observed that the insulin-induced reduction of platelet sensitivity to aggregating agents is a dose-dependent phenomenon. Furthermore, the comparison between the platelet responses after 5 and 30 min of incubation with insulin showed that the insulin effect on platelet aggregation is time dependent. The lack of specificity of its inhibiting activity suggests that insulin does not interfere with the initial binding of each aggregating agent at specific sites but does influence a common step of platelet aggregation. Our study rules out the possibility that insulin reduces platelet-function–modifying intraplatelet cAMP levels or thromboxane A 2 production, because this hormone decreases the platelet concentrations of cAMP–a phenomenon that, per se, promotes platelet aggregation–and does not modify collagen or Na + arachidonate–induced platelet production of thromboxane A 2 , measured by radioimmunoassay of its stable-metabolite thromboxane B 2 . Insulin seems to help in modifying platelet membrane properties, as has already been shown for erythrocytes. The in vivo investigation comprised three studies of the influence of insulin on platelet function in male volunteers: 1 ) a euglycemic-hyperinsulinemic (40-μU/ml) clamp for 90 min followed by 60 min of euglycemia; 2 ) a euglycemic-hyperinsulinemic (160-μU/ml) clamp for 30 min followed by 60 min of euglycemia; and 3 ) an intravenous bolus of human regular insulin (3.84 U/m 2 ). Throughout the three studies, we serially measured platelet sensitivity to ADP, PAF, epinephrine, collagen, and Na + arachidonate. We observed that insulin in vivo and at the physiologic concentration of 40 μU/ml reduced platelet aggregation. For some aggregating agents, we demonstrated a dose and time dependence of the insulin effect. The latter was reversed after the insulin infusion. When insulin was administered as an intravenous bolus and platelet aggregation was studied before the appearance of hypoglycemia, we observed that insulin influence on platelets can be detected after only 10 min. In conclusion, this study suggests that insulin may have a role in the physiological modulation of platelet function and that the long-term insulin deficiency might account for the enhanced platelet aggregability frequently observed in diabetic patients.

Growth and development in simple obesity.

Abstract: It is well known that fat children tend to be taller than their peers and to present a slight acceleration of skeletal and pubertal maturation. To verify this tendency and to examine some of the points that are still controversial, auxological data were studied concerning 303 subjects (141 males and 162 females, aged 6-16 years) affected by simple obesity. Subjects were seen to be taller than average by about 1 SD from 6 to 9 years of age, becoming close to or shorter than average at later ages. Height below the 10th percentile was common in 17% of males and 8% of females, due to hereditary shortness, growth delay or late puberty. Girls had early puberty and menarche; the rate of sexual maturation was variable in boys.

Synthesis and release of platelet-activating factor is inhibited by plasma alpha 1-proteinase inhibitor or alpha 1-antichymotrypsin and is stimulated by proteinases.

Abstract: TNF and IL-1 stimulate the synthesis and release of platelet-activating factor (PAF) by neutrophils and vascular endothelial cells. Serum inhibits PAF production even after inactivation of an acetylhydrolase that degrades PAF. Human plasma was fractionated by gel filtration chromatography, and two inhibitory fractions were detected, one containing PAF-acetylhydrolase activity and the other alpha 1-proteinase inhibitor. Low concentrations of this antiproteinase and of human plasma alpha 1-antichymotrypsin inhibited TNF-induced PAF synthesis in neutrophils, macrophages, and vascular endothelial cells. Both antiproteinases also inhibited PAF production stimulated by phagocytosis in macrophages and induced with IL-1 in neutrophils or with TNF in vascular endothelial cells. These results suggest that a proteinase activated on the plasma membrane or secreted by these cells is involved in promoting PAF synthesis. Indeed, addition of elastase to macrophages, neutrophils, and endothelial cells stimulated synthesis and release of PAF much faster than TNF. A similar stimulation was observed in incubations with cathepsin G. To identify a proteinase activated in TNF-treated cells, neutrophils and endothelial cells were incubated with specific chloromethyl ketone inhibitors of elastase and cathepsin G. Synthesis of PAF was significantly inhibited by low concentrations of the cathepsin G inhibitor. The finding that antiproteinases are inhibitory at concentrations 100-fold lower than those present in plasma raises questions as to the ability of TNF and IL-1 to stimulate neutrophils in circulation or endothelial cells to synthesize PAF. We propose that PAF production is limited to zones of close contact between cells, which exclude antiproteinases.

In vitro and in vivo susceptibility of human leukemic cells to lymphokine activated killer activity.

Abstract: The susceptibility of human myeloid and lymphoid leukemic blasts to the lytic action of recombinant interleukin-2 (rIL-2)-generated lymphokine activated killer (LAK) cells was analyzed. With the exception of the K562 cell line, all 9 leukemic cell lines tested were resistant to the natural killer activity of freshly isolated peripheral blood lymphocytes (PBL) from healthy donors but were susceptible to the lytic action of PBL cultured for 3 days in the presence of rIL-2. Of the 32 primary myeloid and lymphoid acute leukemia samples investigated, the great majority were natural killer cell-resistant but were variably sensitive to LAK effectors. Variations in LAK activity were observed according to the donor of PBL, while little or no difference was documented in the capacity to elicit LAK activity of PBL cultured with 100 or 1,000 U of rIL-2/ml. Pretreatment of the leukemic target cells with neuraminidase did not increase substantially their sensitivity to LAK activity. LAK cells generated from the PBL of patients at the onset of the disease or in complete clinicohematological remission lysed Raji cells as efficiently as normal LAK effectors. Finally, LAK cells were capable of abrogating the tumor growth in nude mice of a human leukemic T cell line. These findings demonstrate the susceptibility in vitro and in vivo of human leukemic blasts to the lytic effect of LAK cells and point to a possible clinical exploitment of this new form of adoptive immunotherapy in the management of acute leukemia.

Effects of timing and type of tobacco in cigarette-induced bladder cancer.

Abstract: We analyzed a case-control study of bladder cancer in Torino (512 male and 55 female cases; 596 male and 202 female controls) with emphasis on the timing of cigarette smoking and the use of black or blond tobacco. The risk of bladder cancer was 2 to 3 times higher among smokers of black tobacco than among smokers of blond tobacco. Both groups of smokers showed a beneficial effect of smoking cessation, with an immediate decline in risk. This pattern is consistent with a late-stage effect of smoking. Among smokers of black tobacco, there was a gradient of risk with early exposure, and smokers who had quit never showed a drop to base-line levels of risk. These patterns, not apparent in users of blond tobacco, suggest an early stage effect of black tobacco, perhaps due to the higher concentration of aromatic amines in black than blond tobacco smoke and the higher blood levels of the hemoglobin adduct with 4-aminobiphenyl (a human bladder carcinogen) among smokers of black tobacco.

A Knowledge Intensive Approach to Concept Induction.

Abstract: In this paper we present a concept acquisition methodology that uses data (concept examples and counterexamples), domain knowledge and tentative concept descriptions in an integrated way. Domain knowledge can be incomplete and/or incorrect with respect to the given data; moreover, the tentative concept descriptions can be expressed in a form which is not operational. The methodology is aimed at producing discriminant and operational concept descriptions, by integrating inductive and deductive learning. In fact, the domain theory is used in a deductive process, that tries to operationalize the tentative concept descriptions, but the obtained results are tested on the whole learning set rather than on a single example. Moreover, deduction is interleaved with the application of data-driven inductive steps. In this way, a search in a constrained space of possible descriptions can help overcome some limitations of the domain theory (e.g. inconsistency). The method has been tested in the framework of the inductive learning system, “ML-SMART,”, previously developed by the authors, and a simple example is also given.

Free cytoplasmic Ca++ at rest and after cholinergic stimulus is increased in cultured muscle cells from Duchenne muscular dystrophy patients.

Abstract: We used a fluorescent dye, quin 2, to measure intracellular free calcium ([Ca + + ] i ) in cultured skeletal muscle cells and skin fibroblasts from five Duchenne muscular dystrophy (DMD) patients and from five controls. We observed an enhanced [Ca + + ] i level, at rest and after acetylcholine (ACh) stimulation, in DMD muscle cells, but we did not detect any difference between DMD and normal skin fibroblasts. The abnormally higher [Ca + + ] i transient induced by ACh suggests that it plays a critical role in muscle degeneration. The skin fibroblast results suggest that there is no generalized membrane defect.

HIV infection acquired by a nurse.

Abstract: We report here the history of the first case of occupationally acquired HIV infection in Italy. Results of serological investigations sequentially performed allow the investigators to outline the natural history of the infection in this case.