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A Celi

Publications and source records attributed to A Celi.

At least 19 recordsLinked to original sources
PubMed1999

ICAM-1-independent adhesion of neutrophils to phorbol ester-stimulated human airway epithelial cells.

Intercellular adhesion molecule-1 (ICAM-1) is the only inducible adhesion receptor for neutrophils identified in bronchial epithelial cells. We stimulated human airway epithelial cells with various agonists to evaluate whether ICAM-1-independent adhesion mechanisms could be elicited. Phorbol 12-myristate 13-acetate (PMA) stimulation of cells of the alveolar cell line A549 caused a rapid, significant increase in neutrophil adhesion from 11 +/- 3 to 49 +/- 7% (SE). A significant increase from 17 +/- 4 to 39 +/- 6% was also observed for neutrophil adhesion to PMA-stimulated human bronchial epithelial cells in primary culture. Although ICAM-1 expression was upregulated by PMA at late time points, it was not affected at 10 min when neutrophil adhesion was already clearly enhanced. Antibodies to ICAM-1 had no effect on neutrophil adhesion. In contrast, antibodies to the leukocyte integrin beta-chain CD18 totally inhibited the adhesion of neutrophils to PMA-stimulated epithelial cells. These results demonstrate that PMA stimulation of human airway epithelial cells causes an increase in neutrophil adhesion that is not dependent on ICAM-1 upregulation.

Bronchi↗
PubMed1998

12-Hydroxyeicosatetraenoic acid upregulates P-selectin-induced tissue factor activity on monocytes.

12-Hydroxyeicosatetraenoic acid (12-HETE), a product of the platelet lipoxygenase pathway, amplifies tissue factor expression by P-selectin-stimulated monocytes in a time- and dose-dependent fashion. The same effect is observed when monocytes are incubated with Chinese hamster ovary cells transfected with the P-selectin cDNA. Both 5-HETE and leukotriene C4 are inactive in this system. Furthermore, the effect is not dependent on non-specific monocyte adhesion, since monocytes incubated with CHO cells expressing E-selectin do not express tissue factor, either in the presence or in the absence of 12-HETE. These results show that 12-HETE is a cofactor for the expression of tissue factor by monocytes.

12-Hydroxy-5,8,10,14-eicosatetraenoic Acid↗
PubMed1998

Serum antibodies to benzo(a)pyrene diol epoxide-DNA adducts in the general population: effects of air pollution, tobacco smoking, and family history of lung diseases.

Polycyclic aromatic hydrocarbons (PAHs) are almost ubiquitous pollutants that may interact with metabolic systems in human tissues and eventually cause cancer. PAH-adducted DNA becomes antigenic and antibodies anti-benzo(a)pyrene diol epoxide (BPDE)-DNA may be found in serum of PAH-exposed subjects. The presence of serum antibodies anti-BPDE-DNA adduct was investigated in 1345 individuals from family clusters of the general population of a small area in central Italy in whom information about smoking habits, site of residence, and personal and family history of lung diseases, including cancer, were obtained. Anti-BPDE-DNA antibodies in the sera were detected with a direct ELISA and the association of anti-BPDE-DNA antibodies with subjects' data from a standardized respiratory questionnaire including age, occupation, tobacco smoking habits, respiratory symptoms, and family history of respiratory diseases was subsequently tested by multivariate logistic regression analysis. The overall prevalence of subjects with anti-BPDE-DNA antibodies was 21.0% (n=283), with no differences between males and females. Anti-BPDE-DNA positivity was associated with living in the urban area [odds ratio (OR), 1.49; 95% confidence interval (CI), 1.16-1.92], with active tobacco smoking (OR, 1.25; 95% CI, 1.06-1.48), and with family history of lung cancer (OR, 1.30; 95% CI, 0.90-1.88), and positivity increased with the number of members in the family cluster positive to anti-BPDE-DNA antibodies (OR, 1.30; 95% CI, 1.03-1.65). This study on a large general population sample indicates that serum anti-BPDE-DNA antibodies may be considered as biomarkers of exposure to environmental carcinogens and of DNA damage. The genetic and familial components of their association with tobacco smoking lend further support to the argument about the familial predisposition to lung cancer.

Adolescent↗
PubMed1998

Cell-cell interaction and tissue factor expression.

Following tissue injury, blood components come into contact with the subendothelial tissue, a thrombogenic surface. Tissue factor, found in the media and adventitia of the vascular wall, or available on the membrane of activated monocytes and endothelial cells, triggers blood coagulation. A complex interaction between soluble molecules and cells then takes place, a fibrin mesh is formed, and the resulting clot limits or stops the loss of blood. Platelets, monocytes, and endothelial cells co-localize and interact in the area of vascular injury. This close relationship, which is regulated by an array of cell-cell adhesion molecules, favours the modulation of the biochemical pathways of these cells. The aim of this review is to summarize the contribution of these cells and their interactions in tissue factor expression and its possible relevance in the pathogenesis of vascular diseases.

Blood Platelets↗
PubMed1997

Presence and persistence of serum anti-benzo[a]pyrene diolepoxide-DNA adduct antibodies in smokers: effects of smoking reduction and cessation.

Among biomarkers of tobacco smoke (TS)-induced genotoxic damage, benzo[a]pyrene diolepoxide-DNA adducts (BPDE-DNA) are extensively studied. Adducted DNA becomes antigenic and antibodies anti-BPDE-DNA (BPDE-DNA-Abs) may be found in serum of exposed subjects. Little is known about the persistence of BPDE-DNA, and no study has been performed to evaluate the persistence of BPDE-DNA-Abs after cessation of exposure. Fifty heavy smokers, enrolled in a smoking cessation program with nicotine patch substitution therapy, were evaluated for the presence of BPDE-DNA-Abs before (w0) and 1, 3, 6 and 12 weeks (w1-12) after the start of the program. Nicotine or placebo patches were randomly assigned to the subjects. BPDE-DNA-Abs were determined in serum by non-competitive ELISA. After the start of the cessation program, 28 subjects quit smoking (group Q) and the other 22 reduced by about 75% the number of cigarettes smoked per day (group R). At the start of the program (w0) 8% of subjects were positive. At w1 the prevalence of positivity had increased both in subjects who quit smoking (Q: 21%) and in subjects who had reduced the number of cigarettes per day (R: 27%). Positivity remained stable up to w12 (21%) for group Q, whereas it increased to 41% in group R. Serum BPDE-DNA-Abs can be detected in smokers, and their persistence for months after smoking cessation suggests their usefulness for relatively long-term surveys. The low percentage of positivity in actual heavy smokers and the increase in antibody positivity with smoking cessation or reduction must be taken into account when interpreting serum BPDE-DNA-Ab measurement in exposed individuals.

7,8-Dihydro-7,8-dihydroxybenzo(a)pyrene 9,10-oxide↗
PubMed1997

Platelet-leukocyte-endothelial cell interaction on the blood vessel wall.

Leukocytes, platelets, and endothelial cells interact at sites of vascular injury and inflammation through adhesion receptors on the cell surface. On binding of ligand to receptor, these receptors initiate intracellular signaling that leads to the modulation of several biological properties of the cells involved. These finely regulated processes involve several classes of cell adhesion molecules: integrins, immunoglobulin-like proteins, selectins, and mucin-like proteins as well as an array of soluble mediators. Interaction of these cell adhesion molecules serves to recruit circulating cells to the blood vessel endothelium or to accumulated platelets on the vessel wall and to foster cell-cell communication. The importance of these interactions to inflammation, blood coagulation, and the immune response is outlined.

Blood Platelets↗
PubMed1996

Detection of N7-methyldeoxyguanosine adducts in human pulmonary alveolar cells.

Alkylating agents may cause DNA damage in different human cells and tissues, including lungs. For instance, tobacco-specific N-nitrosamines are known to produce methyl-DNA adducts, such as N7-methyldeoxyguanosine, and to induce lung tumors. We applied a combined high-performance liquid chromatography (HPLC)/32P-postlabeling technique for measurement of N7-methyldeoxyguanosine in human pulmonary alveolar cells (HPAC). Thirty patients (13 males, 17 females; mean age 51 +/- 17 yr) undergoing bronchoalveolar lavage for diagnosis of nonmalignant lung diseases were studied. DNA was extracted from HPAC, digested to 2'-deoxyribonucleotide 3'-monophosphates and HPLC separated to obtain deoxyguanosine (dGp) and N7-methyldeoxyguanosine (N7-MedGp) monophosphates. Fractions corresponding to normal (1:10,000) and N7-methylated dGp were subsequently 32P-postlabeled by T4 polynucleotide kinase with high specific activity 32P-ATP, resolved by two-dimensional thin-layer chromatography (TLC) and autoradiographed after 3 to 18 h exposure. Spots corresponding to dGp and N7-MedGp were scraped off the plates and quantitated by liquid scintillation counting to calculate direct molar ratios. Recovered HPAC (14.4 +/- 10.0 x 10(6)) were predominantly macrophages (73.8 +/- 16.4%) and lymphocytes (9.8 +/- 11.6%). N7-MedGp was detected in 11 patients, the level ranging from 0.10 to 48.03 fmol/micrograms DNA which corresponded to 0.31-79.00 x 10(-6) N7-MedGp/dGp ratios. Detection of N7-MedGp in HPAC was associated with the smoking habit of patients: N7-MedGp was present in 7 of 10 smokers, 2 of 10 ex-smokers, and 2 of 10 nonsmokers (P < 0.05). These results show that HPAC may be used for molecular dosimetry of DNA damage by alkylating agents, including tobacco-specific N-nitrosamines, in cigarette smokers and thus used for cancer risk assessment.

Adult↗
PubMed1995

Efficacy of transarterial targeted treatments on survival of patients with hepatocellular carcinoma. An Italian experience.

BACKGROUND: Most patients with hepatocellular carcinoma (HCC) are not suitable for surgical therapy. Systemic chemotherapy, immunotherapy, and hormonotherapy have not had convincingly acceptable results. Therefore, transarterial catheter-targeted therapies such as intraarterial chemotherapy (IAC), possibly followed by transcatheter arterial chemoembolization (TACE), have been proposed. METHODS: A survival analysis curve was drawn using the Kaplan-Meier method for 164 patients, 100 with HCC who underwent TACE (69) or IAC (31), and a matched historic group of 64 who did not receive specific antineoplastic treatment. RESULTS: A significantly more favorable survival was observed for TACE-treated patients compared with IAC-treated patients (P < 0.001); TACE- and IAC-treated patients had a statistically superior survival than that of untreated patients (P < 0.001 and P < 0.025, respectively). This difference was still significant (P < 0.001) when the patients were subdivided into Classes A and B and Stages I and II following Child's and Okuda's criteria. The TACE- and IAC-treated groups had a good relationship between technical efficacy of therapy and survival. Stratifying the patients according to the degree of iodized oil (Lipiodol Ultrafluid, Guerbet, Aulnay-Sous-Bois, France) uptake in the three groups with Group 1 having an uptake greater than 75% of tumor mass, Group 2 having an uptake of 50%-75%, and Group 3 having an uptake less than 50%, survival at 6, 12, 24, 36, and 48 months was calculated as 94%, 88%, 67%, 53%, and 30%, respectively, for Group 1; 86%, 68%, 13%, 13%, and 0% for Group 2, and 43%, 23%, 6%, 6%, and 0% for Group 3 (Group 1 vs. Group 2: P < 0.001; Group 1 vs. Group 3: P < 0.001; Group 2 vs. Group 3: P < 0.001, respectively). The most important side effects after the intraarterial procedure were fever (46.2%), abdominal pain (36.6%), chemical cholecystitis (8%), and pancreatitis (1.7%). Death strictly related to treatment occurred in two patients; one had massive bleeding due to ruptured esophageal varices, and the other had a subphrenic abscess of a superficial HCC of the VIII segment. CONCLUSIONS: Transcatheter arterial chemoembolization and IAC were effective and relatively safe, and the authors believe that they have a primary role in treating patients with unresectable HCC larger than 5 cm; iodized oil uptake can be considered a suitable prognostic marker.

Abdominal Pain↗
PubMed1994

P-selectin induces the expression of tissue factor on monocytes.

P-selectin on activated platelets and stimulated endothelial cells mediates cell adhesion with monocytes and neutrophils. Since activated platelets induce tissue factor on mononuclear leukocytes, we examined the effect of P-selectin on the expression of tissue factor activity in monocytes. Purified P-selectin stimulated tissue factor expression on mononuclear leukocytes in a dose-dependent manner. Chinese hamster ovary (CHO) cells expressing P-selectin stimulated tissue factor procoagulant activity in purified monocytes, whereas untransfected CHO cells and CHO cells expressing E-selectin did not. Anti-P-selectin antibodies inhibited the effects of purified P-selectin and CHO cells expressing P-selectin on monocytes. Incubation of CHO cells expressing P-selectin with monocytes leads to the development of tissue factor mRNA in monocytes and to the expression of tissue factor antigen on the monocyte surface. These results indicate that P-selectin upregulates the expression of tissue factor on monocytes as well as mediates the binding of platelets and endothelial cells with monocytes and neutrophils. The binding of P-selectin to monocytes in the area of vascular injury may be a component of a mechanism that initiates thrombosis.

Cell Adhesion Molecules↗
PubMed1994

A rare case of peritoneal mesothelioma in a male with ascites.

Mesothelial lesions can present significant diagnostic problems. An accurate identification of the lesion is important in deciding what course of action to follow, as well as what the required treatment will be. We report the case of a man with untreatable ascites. Four years after the first symptom appeared, the patient suddenly began to lose weight. The CT scan showed a thickening of the peritoneal profile; a diffuse lesion of the mesothelium was then observed at laparotomy. Histological examination led to a diagnosis of malignant mesothelioma in a well-differentiated mesothelial lesion with diffuse involvement of the serosa of the small intestine and the lesser omentum.

Ascites↗
PubMed1991

[The diagnosis of pulmonary embolism: the role of noninvasive technics].

Today a large group of patients with pulmonary embolism is still undetected because this disease is not suspected. We evaluated the role of routine clinical procedures such as history, chest x-ray, electrocardiogram and blood gas analysis in the diagnosis of this disease. We studied 177 patients sent to our observation with suspicion of pulmonary embolism, which was later confirmed in 97 and excluded in 80. Prolonged immobilization, surgical procedures and deep vein thrombosis are the most frequent predisposing factors (P less than 0.05 or less) in patients with pulmonary embolism with respect to patients with unconfirmed suspicion of embolism. Among symptoms and signs, pleuritic chest pain, sudden onset of dyspnea, tachypnea, fever, enlarged jugular veins, enhanced pulmonary component of the second heart sound, pulmonary systolic murmur and basal hypophonesis were the most frequent signs (P less than 0.005 or less) in patients with embolism. Among radiographic signs "sausage" descending pulmonary artery, diaphragmatic elevation, pulmonary infarction, Westermark sign and azygos vein enlargement were more frequent (P less than 0.05 or less) in patients with embolism with respect to patients with unconfirmed suspicion of embolism. Among electrocardiographic signs, tachycardia, P-R segment displacement and negative T wave in V1-V2 were more frequent in patients with embolism with respect to patients with unconfirmed suspicion of embolism (P less than 0.05 or less). PO2, standard pO2 and pCO2 were significantly lower (P less than 0.001) in patients with embolism. After discriminant analysis of the whole data set most patients were correctly classified as embolic (90/97) and non-embolic (75/80).(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Gas Analysis↗
PubMed1991

Dynamic sodium chemical shift imaging for the study of aqueous humor flow.

Ocular images were obtained using sodium chemical shift imaging (CSI) and 1,4,7,10-tetraazacyclododecane-N,N'N",N"'-tetramethylenephospho nate thulium (III) [Tm(DOTP)5-], a paramagnetic chemical shift reagent. After injecting the shift reagent into the anterior chamber of rabbits, serial imaging was done, monitoring the change in chemical shift with time. Sodium CSI produced images of the eye in three dimensions, quantitatively depicting the spatial and temporal changes in the concentration of a paramagnetic tracer substance. The Tm(DOTP)5- is eliminated from the anterior chamber by first-order kinetics with a half-life of 49 min. These data suggest that this substance is eliminated from the anterior chamber at the same rate as aqueous humor is replaced. Sodium CSI shows promise as a valuable technique for monitoring fluid dynamics in the living eye.

Animals↗
PubMed1989

PADGEM protein: a receptor that mediates the interaction of activated platelets with neutrophils and monocytes.

PADGEM (platelet activation dependent granule-external membrane protein) is an integral membrane protein of the alpha granules of platelets and Weibel-Palade bodies of endothelial cells that is expressed on the plasma membrane upon cell activation and granule secretion. Activated platelets, but not resting platelets, bind to neutrophils, monocytes, HL60 cells, and U937 cells. This interaction is inhibited by anti-PADGEM antibodies, PADGEM, and EDTA; anti-GPIIb-IIIa, anti-thrombospondin, anti-GPIV, and thrombospondin produce no effect. Neutrophils and U937 cells, in contrast to Jurkatt cells, contain PADGEM recognition sites, as shown by binding of PADGEM contained in phospholipid vesicles. These results indicate that PADGEM mediates adhesion of activated platelets to monocytes and neutrophils. Therefore, PADGEM shares not only structural but also functional homology with ELAM-1 and MEL-14, members of a new family of vascular cell adhesion molecules.

Antibodies, Monoclonal↗
PubMed1989

Prospective study of a standardized questionnaire to improve clinical estimate of pulmonary embolism.

A standardized questionnaire was administered to 100 patients suspected of having pulmonary embolism to investigate whether clinical data may be reliably used in the decision-making process of such patients. Questionnaire data were compared with lung scintigraphy outcome and 16 variables were selected as significantly associated with the scintigraphic diagnosis. Based on these variables, patients with abnormal scintigraphy compatible with pulmonary embolism and patients with scintigraphy not compatible with embolism were classified in accordance with the scintigraphic diagnosis. When these 16 variables were tested in an additional validation group, clinical and scintigraphic diagnosis matched in most cases. These results show that clinical data can be used to predict the outcome of lung perfusion scintigraphy in patients suspected of pulmonary embolism. Use of a standardized questionnaire can improve the accuracy of pretest assessment of such patients and positively influence the decisions to start heparin coverage or obtain pulmonary angiography.

Electrocardiography↗
PubMed1988

A computer-based method for on-line acquisition and analysis of bronchial challenge test.

We developed a computer program for the optimization and management of data collection in order to compute the change of forced expiratory volume in the first second (delta FEV1), provocative doses and to plot the dose-response curve for bronchial challenge test. Doses of methacholine are entered via the keyboard and forced vital capacity (FVC) with the highest FEV1 value obtained in each step is selected. When the imposed threshold of response has been reached, doses of administered methacholine and corresponding spirometric parameters are displayed and printed. Dose-response relationships are analysed: the increase of delta FEV1 for each unit of metacholine is computed in the interval between the two doses where delta FEV1 reached one of the imposed values (i.e. 15% or 20% or 30%). Finally spirometric values, dose-response curve and provocative doses are shown in a print-out. Computer values of provocative doses are higher than those obtained manually. This difference may be ascribed to the incorrect manual linear extrapolation. In conclusion the computer program is able to reduce consistently the time spent to analyze data from bronchial challenge test and allows a more precise determination of provocative doses by avoiding also inter-intra individual errors.

Asthma↗