Search results for "fluidit"

Effect of Combined Physical Stresses on Cells: The Role of Water

2010

International audience; The role of water in microorganism viability was assessed through the application of combined physical perturbations. The combination of different physical parameters could allow to balance the properties variations (especially water related) resulting from the increase of one parameter alone. Thus, it is possible to optimize the survival of cells in controlling these parameters. This was tested through two different examples. The first example shows that combination of osmotic level and temperature can allow optimizing yeast cell survival in following membrane fluidity variation. Moreover this analysis has allowed a better comprehension of cell inactivation during r…

Parvovirus capsid disorders cholesterol-rich membranes.

2008

In this study canine parvovirus, CPV, was found to induce disorder in DPPC:cholesterol membranes in acidic conditions. This acidicity-induced fluidizing effect is suggested to originate from the N-terminus of the viral capsid protein VP1. In accordance with the model membrane studies, a fluidizing effect was seen also in the endosomal membranes during CPV infection implying an important functional role of the fluidization in the endocytic entry of the virus.

Diabetes mellitus: mean erythrocyte aggregation, glycometabolic pattern, red cell Ca2+ content, and erythrocyte membrane dynamic properties.

1993

Polymorphonuclear leukocyte membrane fluidity and cytosolic Ca2+ concentration in diabetes mellitus.

1998

We evaluated polymorphonuclear membrane (PMN) fluidity in 32 subjects with type 1 diabetes mellitus, 38 subjects with type 2 diabetes mellitus and 38 normal control subjects, by marking intact and unstimulated PMN cells with the fluorescent probe 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene (TMA-DPH). We also evaluated PMN cytosolic Ca2+ content by marking intact and unstimulated PMN cells with the fluorescent probe Fura 2-AM. PMN membrane fluidity differentiated normal subjects from type 1 and 2 diabetic subjects. The PMN cytosolic Ca2+ concentration did not discriminate type 1 and 2 diabetic subjects from normal control subjects. No statistical correlation was found between PMN …

Cytosolic Ca2+Content and Membrane Fluidity of Platelets and Polymorphonuclear Leucocytes in Diabetes Mellitus

1995

Considering the role played by platelets and leucocytes in diabetic disease and keeping in mind the strong correlation between functional and metabolic aspects that characterizes this clinical condition, we evaluated, in two groups of diabetics, respectively the platelet and polymorphonuclear (PMN) cytosolic Ca2+ content (employing the fluorescent probe Fura 2-AM) and membrane fluidity (using the fluorescent probe TMA-DPH and considering the fluorescence polarization degree, inversely related to the membrane fluidity). From the obtained results, it is evident that the platelet cytosolic Ca2+ content does not distinguish normals from diabetics of type 1 and 2; the platelet membrane fluidity …

Deep Venous Thrombosis: Leukocyte Rheology at Baseline and after in vitro Activation

2001

We evaluated leukocyte rheology, expressed as leukocyte filtration, polymorphonuclear (PMN) membrane fluidity and cytosolic Ca<sup>2+</sup> concentration in subjects with acute deep venous leg thrombosis (DVT). In 14 subjects with leg DVT we examined the leukocyte filtration [unfractionated, mononuclear cells (MN), PMNs], PMN membrane fluidity and PMN cytosolic Ca<sup>2+</sup> concentration. Subsequently, we evaluated the same PMN variables after in vitro chemotactic activation with 4-phorbol-12-myristate-13-acetate. At baseline, we observed a significant difference in the filtration of unfractionated and MNs and in PMN cytosolic Ca<sup>2+</sup> concentra…

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 integrins, membrane fluidity, and cytosolic Ca(2+) content after activation in essential hypertension.

2000

Abstract —The purpose of this research was to obtain further information about the role of polymorphonuclear leukocytes in essential hypertension. These cells could be involved in the pathogenesis of organ injury. Thirty subjects (14 men and 16 women) with essential hypertension were enrolled. In these subjects we determined, at baseline and after in vitro activation with 4-phorbol 12-myristate 13-acetate and N -formyl-methionyl-leucyl-phenylalanine, the polymorphonuclear leukocyte membrane fluidity, obtained by labeling the cells with 1-[4-(trimethylamino)phenyl]-6-phenyl-1,3,5-hexatriene, cytosolic Ca 2+ concentration, obtained by marking the cells with Fura 2-AM, and integrin pattern (C…

Polymorphonuclear leukocyte membrane fluidity and insulin resistance in obese subjects.

2002

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…