Search results for "Neutrophil Activation"
showing 10 items of 24 documents
Marathon Race Affects Neutrophil Surface Molecules: Role of Inflammatory Mediators
2016
The fatigue induced by marathon races was observed in terms of inflammatory and immunological outcomes. Neutrophil survival and activation are essential for inflammation resolution and contributes directly to the pathogenesis of many infectious and inflammatory conditions. The aim of this study was to investigate the effect of marathon races on surface molecules related to neutrophil adhesion and extrinsic apoptosis pathway and its association with inflammatory markers. We evaluated 23 trained male runners at the Sao Paulo International Marathon 2013. The following components were measured: hematological and inflammatory mediators, muscle damage markers, and neutrophil function. The maratho…
β-Adrenoceptor stimulation up-regulates phosphodiesterase 4 activity and reduces prostaglandin E 2 -inhibitory effects in human neutrophils
2000
Human neutrophils were treated for 4 h with a combination of salbutamol (1 µM), a β2-adrenoceptor agonist, and rolipram (30 µM), a selective phosphodiesterase 4 inhibitor, to investigate whether this treatment produces up-regulation of phosphodiesterase activity with functional consequences. Anion-exchange chromatography coupled with the use of selective activators and inhibitors demonstrated that a phosphodiesterase activity with characteristics of the isoenzyme type 4 was increased in drug-treated cells. Kinetic analysis showed a ~1.5-fold increase in V max without alteration of K m values. The augmented phosphodiesterase activity in drug-treated cells was abolished by actinomycin D. Cycl…
The impact of two whole blood inline filters on markers of coagulation, complement and cell activation
2005
Background and Objectives There exists a current lack of information about the impact of different inline filters, used for the leucoreduction of whole blood (WB), on the levels of clotting factors and markers of coagulation, complement and cell activation in plasma. Only a few small comparisons of different types of WB inline filters have been published to date. Materials and Methods This study compared two plasma types of 200 units each. Both study groups were derived from WB, inline-filtered and held for 2 h at 20° between donation and filtration. Then, 200 units (Group A) were filtered using a positively charged polyester filter (Baxter RZ2000) and the other 200 units (Group B) were f…
Airway neutrophilia in COPD is not associated with increased neutrophil survival
2006
Neutrophilic airway inflammation is a prominent feature of chronic obstructive pulmonary disease (COPD) and correlates with disease severity. The mechanisms that determine the extent of neutrophilia could involve increased influx or prolonged survival of neutrophils. The aim of the study was to assess whether neutrophil pro-survival mechanisms are increased in the airways of subjects with COPD owing to the presence of anti-apoptotic factors in the bronchial lining fluid. Induced sputum samples were collected from 20 subjects with stable COPD, 14 healthy smokers and 14 healthy controls. Quantification of apoptotic neutrophils was based on typical morphological cell changes. Anti-apoptotic, p…
Deep venous thrombosis: Behaviour of the polymorphonuclear leukocyte integrin pattern at baseline and after in vitro activation
2005
In a group of 18 subjects with acute deep venous thrombosis (DVT), evidenced by clinical examination and echo-color-Doppler, we examined the phenotypical expression of the polymorphonuclear leukocyte (PMN) beta2-integrins (CD11a, CD11b, CD11c, CD18), obtained by using a flow cytofluorimeter. The evaluation was performed before and after in vitro activation (prolonged for 5 and 15 minutes) with 4-phorbol 12-myristate 13-acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (fMLP). In DVT subjects, at baseline, the phenotypical expression of CD11b was decreased and that of CD11c was increased when compared with normal controls; no difference was found in CD11a and CD18 expression. In norm…
Polymorphonuclear leukocyte membrane fluidity before and after activation in subjects with insulin resistance.
2000
The aim of this research was the evaluation of polymorphonuclear leukocyte (PMN) membrane fluidity in subjects with insulin resistance. Insulin sensitivity, in fact, may be influenced by plasma membrane fluidity. We enrolled 19 subjects with insulin resistance previously demonstrated during an euglycemic hyperinsulinemic clamp. PMN membrane fluidity was studied by labeling intact cells with the fluorescent probe 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene and calculating the fluorescence polarization degree. The measurement was made before and after incubation of PMNs with two activating agents: 4-phorbol 12-myristate 13-acetate (PMA) and N-formyl-methionyl-leucyl-phenylalanine (…
Polymorphonuclear leukocyte membrane fluidity, at baseline and after in vitro activation, in obesity with or without diabetes mellitus
2002
We studied a group of 28 obese subjects (mean age 38.2+/-13.5 years, body mass index 35.0+/-5.6 kg/m2) with insulin resistance demonstrated employing an euglycemic hyperinsulinemic clamp, subdivided into a subgroup with normal glucose tolerance (NGT) and a subgroup with type 2 diabetes mellitus (DM). We examined the polymorphonuclear leukocyte (PMN) membrane fluidity at baseline and after activation with 4-phorbol 12-myristate 13-acetate (PMA) or N-formyl-methionyl-leucylphenylalanine (fMLP). At baseline, PMN membrane fluidity was significantly decreased in both subgroups compared to normals. In obese subjects with NGT no correlation was found between this PMN determinant and the parameters…
Airway cells after swimming outdoors or in the sea in nonasthmatic athletes
2003
BONSIGNORE, M. R., G. MORICI, L. RICCOBONO, M. PROFITA, A. BONANNO, A. PATERNO, R. DI GIORGI, L. CHIMENTI, P. ABATE, F. MIRABELLA, A. M. VIGNOLA, and G. BONSIGNORE. Airway Cells after Swimming Outdoors or in the Sea in Nonasthmatic Athletes. Med. Sci. Sports Exerc., Vol. 35, No. 7, pp. 1146–1152, 2003. Marathon runners and elite swimmers showed increased inflammatory cells in the airways at baseline. Although airway neutrophils increase further after a marathon race, the airway response to swimming is unknown. The aim of this study was to assess the effects of swimming on airway cells. To avoid the concomitant effects of chronic exposure to chlorine, the study was conducted in seven nonasth…
Diabetes mellitus: Polymorphonuclear leukocyte (PMN) filtration parameters and PMN membrane fluidity after chemotactic activation
1999
Abstract The goal of this research was to determine leukocyte rheology at baseline and after chemotactic activation in type I and type II diabetics. In 19 normal subjects, 21 type I diabetics, and 16 type II diabetics at baseline and after in vitro chemotactic activation (prolonged for 5 and 15 minutes) with two stimulating agents (4-phorbol 12-myristate 13-acetate [PMA] and N -formyl-methionyl-leucyl-phenylalanine [fMLP]), we evaluated polymorphonuclear (PMN) filtration parameters (using a St. George filtrometer [Carri-Med, Dorking, UK] and considering the initial relative flow rate [IRFR] and the concentration of clogging particles [CP]) and PMN membrane fluidity (obtained by marking PMNs…
TREM-1 ligand expression on platelets enhances neutrophil activation
2007
Abstract The triggering receptor expressed on myeloid cells 1 (TREM-1) plays an important role in the innate immune response related to severe infections and sepsis. Modulation of TREM-1–associated activation improves the outcome in rodent models for pneumonia and sepsis. However, the identity and occurrence of the natural TREM-1 ligands are so far unknown, impairing the further understanding of the biology of this receptor. Here, we report the presence of a ligand for TREM-1 on human platelets. Using a recombinant TREM-1 fusion protein, we demonstrate specific binding of TREM-1 to platelets. TREM-1–specific signals are required for the platelet-induced augmentation of polymorphonuclear leu…