We examined at baseline and after activation with N-formyl-methionyl-leucylphenylalanine (fMLP) the polymorphonuclear (PMN) leukocyte rheology expressed not only as filtration parameter (using the St. George's Filtrometer) but also as membrane fluidity (employing the fluorescent probe TMA-DPH) and cytosolic Ca2+ concentration (adopting the fluorescent probe Fura-2AM) in a group of subjects with vascular atherosclerotic disease (VAD), in a group of VAD subjects with type 2 diabetes mellitus (DM), in a group of type 1 diabetics, in a group of type 2 diabetics, in a group of hypertensives and in a group of subjects with chronic renal failure (CRF), The obtained results show that after activation the PMN filtration parameter (IRFR) was significantly and constantly reduced in normals and in all the examined groups although this reduction was more evident in diabetics of both types, in hypertensives and in CRF subjects. The PMN membrane fluidity after activation decreased significantly only in type 1 diabetics and in CRF subjects while PMN cytosolic Ca2+ content did not show any significant variation in normal controls and in CRF subjects. These data underline how the PMN rheological pattern needs to be examined at baseline and after activation, even if the mechanisms of these variations are not always demonstrated.

Asthmatic subjects can only be allowed to take part in sport activities after a careful functional evaluation of pulmonary function. For sport disciplines which require a mainly anaerobic metabolism it is enough to evaluate the respiratory function at rest, while for sport disciplines which require a mainly aerobic metabolism it is necessary to use an exercise tolerance test. The functional tests used must be able to demonstrate not only the suitability of the subjects to take up a sport, but also to recommend an appropriate sport discipline.

We measured the plasma lipid levels and the macrorheologic (whole-blood, plasma, and serum viscosity levels; fibrinogen; hematocrit; mean erythrocyte aggregation; and whole-blood filterability) and microrheologic (erythrocyte membrane fluidity and red cell membrane protein lateral mobility) determinants in a group of 19 hyperlipidemic patients (Fredrickson's classification phenotype IIa, 12 patients; phenotype IV, 4; phenotype IIb, 3) at baseline and after 45 and 90 days of treatment with gemfibrozil (900 mg orally once a day). At baseline we noted statistically significant increases in plasma viscosity level, fibrinogen, and mean erythrocyte aggregation, as well as a statistically significant decrease in whole-blood filterability, erythrocyte membrane fluidity, and red cell membrane protein lateral mobility in hyperlipidemic patients compared with healthy subjects, The gemfibrozil treatment provided a statistically significant decrease of the plasma lipid levels, but had little effect on the hemorheologic profile.

In diabetics of type 1 and 2 we examined, in resting white blood cells (WBC), the filtration parameters (Initial Relative Flow Rate - IRFR, Clogging Rate - CR) employing the St. George Filtrometer, the polymorphonuclear cells (PMN) membrane fluidity, the PMN cytosolic Ca2+ content and the PMN membrane cholesterol/phospholipid ratio (C/PL). From the obtained data, it is evident that, while the IRFR of unfractionated WBC distinguishes normals from diabetics of type 1 and 2, the filtration parameters of the PMN and mononuclear cells (MN) do not show any significant difference. PMN membrane fluidity, PMN cytosolic Ca2+ content and PMN C/PL do not discriminate normals from diabetics of type 1 and 2. No relationship is evident between WBC filtration and metabolic parameters (fasting blood glucose level, serum cholesterol and triglycerides); no correlation is present between PMN filtration parameters, PMN membrane fluidity and PMN metabolic determinants (cytosolic Ca2+, C/PL).

We examined the platelet membrane fluidity, the platelet cytosolic Ca2+ content, and the correlations between them in diabetics subdivided for type (insulin-dependent diabetes mellitus - IDDM and non-insulin-dependent diabetes mellitus NIDDM), in subjects with essential hypertension, in subjects with vascular atherosclerotic disease (VAD), and in VAD subjects with NIDDM. The platelet membrane fluidity did not differentiate normals from diabetics, nor did it distinguish normals from hypertensives. This parameter discriminated IDDM from NIDDM and normals from VAD subjects with and without NIDDM. The platelet cytosolic Ca2+ content did not distinguish normals from diabetics, hypertensives, VAD subjects with and without NIDDM. The platelet membrane fluidity was related to the cytosolic Ca2+ content in hypertensives only.

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 instead does not discriminate normals from diabetics, but differentiates diabetics of type 1 and 2 (type 1 = 0.284 +/- 0.015; type 2 = 0.314 +/- 0.018; p < 0.001). PMN cytosolic Ca2+ content and membrane fluidity do not discriminate normals from diabetics. In the two groups of diabetics none of the platelet and PMN parameters (cytosolic Ca2+ content and membrane fluidity) are related to the glycometabolic pattern.

OBJECTIVE:To evaluate platelet membrane fluidity and some platelet metabolic parameters in type II diabetic patients with macrovascular complications.RESEARCH DESIGN AND METHODS:In a group of 21 type II diabetic patients with macrovascular complications, we evaluated platelet membrane fluidity [marking intact resting platelets with the fluorescent probe 1,4-(trimethylamino)-phenyl-4-phenylhexatriene (TMA-DPH)], platelet membrane lipid pattern (cholesterol:phospholipid [C:PL] ratio and individual phospholipids), and platelet cytosolic Ca2+ content (marking intact resting platelets with the fluorescent probe Fura 2AM).RESULTS:Platelet membrane fluidity is decreased in type II diabetic patients with macrovascular complications compared with normal subjects (P < 0.001). Platelet membrane C:PL ratio and cytosolic Ca2+ content do not discriminate normal subjects from diabetic patients, and for individual phospholipids, only phosphatidylethanolamine is decreased in diabetic patients compared with control subjects (P = 0.051). In normal subjects, the polarization degree of TMA-DPH is related to phosphatidylserine (P < 0.05) and phosphatidylcholine (P < 0.05), and in diabetic patients the polarization degree of TMA-DPH is related to C:PL ratio (P < 0.05) and sphyngomyelin (P < 0.05).CONCLUSIONS:In type II diabetic patients with macrovascular complications, we observed an abnormality of platelet membrane fluidity, which may contribute to platelet functional alteration present in this clinical condition.

In a group of subjects with essential hypertension platelets were studied in resting conditions: platelet membrane fluidity was measured with the fluorescent probe 1.4-(trimethylamino)-phenyl-4-phenylhexatriene (TMA-DPH), platelet membrane cholesterol/phospholipid ratio was evaluated separating the membrane lipids with column chromatography, and platelet membrane individual phospholipids were determined using two-dimensional thin-layer chromatography. From the obtained results, it is evident that platelet membrane fluidity does not differentiate normals from hypertensives; platelet membrane cholesterol/phospholipid ratio is increased in hypertensives, while of the platelet membrane individual phospholipids, only the phosphatidylcholine is increased. In normals and hypertensives, no relation is evident between platelet membrane fluidity, platelet membrane lipid pattern, and systolic and diastolic blood pressure values.

In a group of subjects with vascular atherosclerotic disease (VAD) we examined the platelet membrane fluidity (obtained marking intact resting platelets with TMA-DPH), the platelet membrane cholesterol/phospholipid ratio (C/PL - using column chromatography), the platelet membrane individual phospholipids (employing the thin layer chromatography) and the platelet cytosolic Ca2+ content (evaluated marking intact resting platelets with Fura 2-AM). From the obtained data, it is evident that platelet membrane fluidity differentiates normals from VAD subjects. Platelet membrane lipid pattern (C/PL and individual phospholipids) and cytosolic Ca2+ content do not discriminate normals from VAD subjects. In normals the polarization degree of TMA-DPH is significantly correlated to the phosphatidylserine and phosphatidylcholine, while in VAD subjects no relationship is present between the polarization degree of TMA-DPH and the platelet metabolic parameters.

A study was carried out in 10 patients with vascular atherosclerotic disease to investigate the effects of a single 800-mg dose of defibrotide, given by intravenous infusion, on parameters reflecting red blood cell (RBC)-membrane dynamic properties. At baseline and 60 minutes postinfusion, measurements were made of whole-blood filterability and aggregation, as well as RBC membrane fluidity and protein lateral mobility. Significant increases were noted in whole-blood filterability and RBC membrane fluidity following defibrotide. The results suggest that this molecule influences the hemorheologic pattern of the RBC membrane.

Defibrotide is a single-strand polydeoxyribonucleotide, obtained by controlled depolymerization of DNA extracted from mammalian organs. It stimulates vascular prostacyclin production and secretion (1-3) and enhances fibrinolysis (1, 4-6). Several clinical trials have evidentiated that defibrotide is effective in the prophylaxis of deep vein thrombosis and in the treatment of peripheral obliterative arterial disease (for a review see ref. 7). There are several reports concerning, in vitro and in vivo, the dose-dependent activity of defibrotide on the polymorphonuclear leucocytes (PMN). From these results, the molecule influences the PMN adhesivity (8, 9) and especially PMN activation, with secondary decrease or inhibition of free radical (superoxide anion) synthesis (10, 11). Other authors point out that this molecule interferes with the leucocyte role in the genesis of thrombosis (12). There is, however, no information about the action of defibrotide on white blood cell (WBC) rheology. Considering all these [mdings, we studied the influence of defibrotide on WBC filtration, PMN membrane fluidity and cytosolic Ca2+ content in a group of subjects with vascular atherosclerotic disease (V AD).

In a group of 22 subjects with essential hypertension we evaluated the red cell filterability and aggregation, the erythrocyte membrane fluidity and red cell membrane transverse fluidity gradient. we also evaluated the total red cell Ca2+ content, the red cell cytosolic free Ca2+ content, the red cell membrane cholesterol/phospholipid ratio and the red cell membrane individual phospholipids. From our results, it is evident that the macrorheological as well as the microrheological determinants discriminate normals from hypertensives. From our data, a significant increase of the total and cytosolic red cell Ca2+ content is evident in hypertension. In hypertensives, the evaluation of the red cell lipid parameters shows that only the CL/PL ratio plays a discriminant role. The study of correlations between the microrheological determinants and red cell metabolic parameters shows interesting findings.

The American College of Cardiology/American Heart Association (ACC/AHA) Task Force on Practice Guidelines has recently released the new cholesterol treatment guideline. This update was based on a systematic review of the evidence and replaces the previous guidelines from 2002 that were widely accepted and implemented in clinical practice. The new cholesterol treatment guideline emphasizes matching the intensity of statin treatment to the level of atherosclerotic cardiovascular disease (ASCVD) risk and replaces the old paradigm of pursuing low-density lipoprotein cholesterol targets. The new guideline also emphasizes the primacy of the evidence base for statin therapy for ASCVD risk reduction and lists several patient groups that will not benefit from statin treatment despite their high cardiovascular risk, such as those with heart failure (New York Heart Association class II-IV) and patients undergoing hemodialysis. The guideline has been received with mixed reviews and significant controversy. Because of the evidence-based nature of the guideline, there is room for several questions and uncertainties on when and how to use lipid-lowering therapy in clinical practice. The goal of the Mayo Clinic Task Force in the assessment, interpretation, and expansion of the ACC/AHA cholesterol treatment guideline is to address gaps in information and some of the controversial aspects of the newly released cholesterol management guideline using additional sources of evidence and expert opinion as needed to guide clinicians on key aspects of ASCVD risk reduction.

In several groups of subjects with different clinical conditions: vascular atherosclerotic disease (VAD), VAD with diabetes mellitus of type 2 (NIDDM), diabetes mellitus of type 1 and diabetes mellitus of type 2 without macrovascular complications, essential hypertension and chronic renal failure (CRF), we evaluated the red cell Ca2+ content (total and cytosolic), the erythrocyte membrane fluidity and the correlations between them. The total red cell Ca2+ content does not differentiate normals from VAD subjects with and without NIDDM and normals from diabetics of type 1 and 2, but it does discriminate normals from hypertensives and normals from CRF subjects. The cytosolic red cell Ca2+ content does not distinguish normals from VAD subjects, while it clearly differentiates normals from VAD subjects with NIDDM, normals from diabetics of type 1 and 2, normals from hypertensives and normals from CRF subjects. In all these clinical conditions the erythrocyte membrane fluidity is reduced compared to controls; the erythrocyte membrane fluidity is not related to the total red cell Ca2+ content in each of these clinical conditions, while it is related to the cytosolic red cell Ca2+ content in type 2 diabetics, in hypertensives and in CRF subjects.

In a group of 24 diabetics subdivided for type, we evaluated the red cell membrane protein lateral mobility marking intact red cells with pyrene-3-maleimide (3-PM) and calculating the dimer to monomer fluorescence intensity ratio (Iex/Im). The same fluorescent parameter was determined in a group of 13 normal controls. From the obtained data, it is evident that the red cell membrane protein lateral mobility clearly discriminates normals from diabetics of type 1 and 2. In normals and in diabetics of type 1 and 2 no relationship is present between this fluorescent determinant and the glycometabolic parameters (FBGL and HbA1c); considering all the diabetics, a negative relationship is evident between Iex/Im ratio and HbA1c only.

Sixteen patients with chronic cerebrovascular disease were treated with a monotherapeutic regimen of nimodipine 30 mg orally three times a day. At baseline and after 45 and 90 days of therapy, the patients' whole blood filterability, erythrocyte membrane fluidity, red blood cell membrane protein lateral mobility, and red blood cell Ca2+ content (total and cytosolic) were evaluated. After 45 days, an increase in whole blood filterability and a decrease in the cytosolic red cell Ca2+ content was seen. At the end of treatment, whole blood filterability, erythrocyte membrane fluidity, and red cell membrane protein lateral mobility had increased, compared with baseline values, while the total and cytosolic red cell Ca2+ content had significantly decreased. These findings demonstrate that nimodipine not only influences red blood cell calcium but also acts on the macro- and microrheologic patterns.

In a group of 10 subjects with vascular atherosclerotic disease (VAD) and in a group of 15 VAD subjects with non-insulin-dependent diabetes mellitus (NIDDM), treated in monotherapy with mesoglycan, we examined, at baseline and after 30 days the erythrocyte membrane fluidity. From the obtained results, it is evident that in both groups the treatment with mesoglycan is responsible for an increase of this microrheological parameter.

In a group of subjects with essential obesity, in a group of obese subjects with non-insulin dependent diabetes mellitus (NIDDM), and in a group of obese subjects with impaired glucose tolerance (IGT), we evaluated whole-blood filtration, mean erythrocyte aggregation, erythrocyte membrane fluidity and red cell lipid pattern. From these data, it is evident that the macro- and microrheological determinants are able to discriminate normals from each group of obese subjects. Regarding the red cell lipids, few are the variations between each group of obese subjects and normal controls.

In a group of 21 subjects with vascular atherosclerotic disease (VAD) we evaluated the cytosolic red cell Ca2+ content (employing Fura-2AM), the total red cell Ca2+ content (using an atomic absorption spectrophotometer) and the erythrocyte membrane fluidity (marking intact red blood cells with pyrene).From the obtained results, it is evident that cytosolic and total red cell Ca2+ content do not distinguish normals from VAD subjects. Erythrocyte membrane fluidity discriminates normals from VAD subjects. No relationship is present between erythrocyte membrane fluidity, total and cytosolic red cell Ca2+ content.