Modulation of RAGE expression influences the adhesion of red blood cells from diabetic patients.

Atherothrombotic complications are frequent in patients with type 2 diabetes. Red blood cells (RBC) from diabetic patients exhibited an increased adhesion which correlated to the extent of vascular complications. In the present study we have investigated the adhesive interactions of RBCs with endothelium, using flow-based assessments.

A multicenter, double-blind, safety study of QR-333 for the treatment of symptomatic diabetic peripheral neuropathy. A preliminary report.

Background: QR-333, a topical compound that contains quercetin, a flavonoid with aldose reductase inhibitor effects, ascorbyl palmitate, and vitamin D(3), was formulated to decrease the oxidative stress that contributes to peripheral diabetic neuropathy and thus alleviate its symptoms. This proof-of-principle study assessed the efficacy and safety of QR-333 against placebo in a small cohort of patients with diabetic neuropathy.

Methods: This randomized, placebo-controlled, double-blind trial included 34 men and women (21-71 years of age) with Type 1 or 2 diabetes and diabetic neuropathy who applied QR-333 or placebo (2:1 ratio), three times daily for 4 weeks, to each foot where symptoms were experienced.

Measurements of transcutaneous oxygen pressure and changes in blood rheology as markers of prognosis of critically ischemic limb in diabetes mellitus patients.

The aims of this study were to compare variations of the transcutaneous oxygen pressure (TcPO(2)) and blood rheology in diabetic patients. Diabetic patients with critical limb ischemia were compared with those who were either asymptomatic or had mild peripheral vascular disease (PVD). The results showed a significant decrease in TcPO(2) in patients with critical limb ischemia.

Blood rheology as a marker of venous hypertension in patients with venous disease.

During chronic venous insufficiency (CVI), several microvascular functional abnormalities, due to venous hypertension, develop. To look for blood rheological consequences of venous hypertension "VH", whole blood viscosity and its main determinants were measured in 11 normal controls and 36 patients with CVI exposed to a short-term experimental VH. Patients were subdivided into 2 groups according to the severity of their disease.

Blood rheology in patients with diabetes mellitus.

Blood rheology is now receiving increasing attention as an important potential contributory factor to diabetic angiopathy. This study was designed to provide evidence for and against early hemorheological abnormalities in diabetes mellitus (DM). For this purpose, blood viscosity, RBC aggregation, hematocrit, and plasma protein's levels of both fibrinogen and albumin were measured in 86 uncomplicated patients with DM (45 type 1 and 41 type 2).

Hemorheological disturbances as a marker of diabetic foot syndrome deterioration.

Diabetes mellitus is associated with vascular abnormalities. Hemorheological variables as well as the transcutaneous oxygen pressure (TcPO2) were measured in 38 diabetic patients with critical limb ischemia to assess whether these variables could be of value to follow the deterioration in foot disease. Patients with previous history of foot ulcers or frank ulcers on presentation were followed for foot care.

Sensitivity of the ultrasonic interferometry method (Echo-Cell) to changes of red cell aggregation: application to diabetes.

The sensitivity of the ultrasonic interferometry method (Echo-Cell) to changes in red blood cell (RBC) aggregation was investigated in comparison to the Regulest erythroaggregometry known as a reference method. In experiments where different concentrations of dextrans of 40 or 70 kD molecular weights were added to normal RBCs, the Echo-Cell was proved as sensitive as erythroaggregometry. A comparative study using RBC samples from normal and diabetic subjects showed that the Echo-Cell was much more sensitive when aggregation was measured in diluted than undiluted plasma.

Impaired hemorheological properties in diabetic patients with lower limb arterial ischaemia.

The rheological properties of blood play an important role in the regulation of blood flow resistance in vessels. Numerous data show evidence for an impaired hemorheological characteristic in diabetes mellitus. The aim of this study was to investigate whether chronic severe leg ischaemia in diabetes may be associated with further hemorheologic impairment.

Effect of naftidrofuryl on platelet aggregation in plasma from aspirin treated patients: an in vitro study.

This study concerns an in vitro evaluation of the effect of naftidrofuryl on platelet aggregation in plasma of 15 diabetic patients, who were being treated with aspirin, and who were suffering from chronic arterial disease of the lower limbs. Platelet aggregation, induced either spontaneously or by aggregating agents, was measured in platelet-rich plasma (PRP). The results show that serotonin (5-HT)- and adenosine 5'-diphosphate (ADP)-induced platelet aggregation significantly decreased after addition of naftidrofuryl.

Tissular oxygenation and venoarteriolar reflex disturbances in diabetes mellitus: vasoregulator effect of Buflomedil.

The present study was designed to investigate whether the Veno-Arteriolar Reflex (VAR) mediated via a local nervous reflex mechanism may be used as a microvascular approach to predict the effect of vasoactive drugs in diabetic patients. The vasoactive drug we studied here was Buflomedil. The effect of a single infusion of 400 mg of Buflomedil was examined on VAR and on transcutaneous oxygen pressure (TcPO2).

[Diabetes mellitus and fibrinogen. Hemorrheological and microcirculatory consequences].

Fibrinogen level, erythrocyte aggregation and transcutaneous oxygen pressure (TcPO2) were measured in the two populations of 32 healthy volunteer subjects and 119 diabetic patients without any clinical sign of micro and/or macroangiopathy. Measured parameters were studied according to both the long term glycemic control (HbA1C) and the type of diabetes. Results showed a significant elevation of plasma fibrinogen in all diabetic patients even when they had good glycemic control.

Haemorheological consequences of hyperglycaemic spike in healthy volunteers and insulin-dependent diabetics.

The present study has been designed to examine the role of a hyperglycaemic spike of short duration as a factor possibly involved in haemorheological microcirculatory and (or) haemostatic dysfunctions in ten insulin-dependent diabetes mellitus patients (IDDM) and five healthy volunteers. The hyperglycaemic spike was induced by glucose infusion via GCIIS Biostator. Blood viscosity, erythrocyte aggregation, erythrocyte deformability, plasma viscosity and proteins' levels, cell counts, and transcutaneous oxygen pressure were investigated during normoglycaemic period and at the end of a 1 h hyperglycaemic spike.

Role and limits of glycemic regulation in the pathogenesis of diabetic microangiopathy.

The relationship between either an acute or a chronic hyperglycemia and functional microcirculatory disturbances was studied in insulin-dependent diabetic (IDD) patients in comparison to healthy volunteers. Acute hyperglycemia, provoked in 10 IDD patients, was accompanied by an increase in laser doppler skin blood flux while transcutaneous oxygen pressure (TcPO2) decreased. These changes, accompanied by that in the concentration of moving blood cells indicate that acute hyperglycemia results in a vasodilation in favour of non-nutritive microvascular shunts.

The autoregulation of the skin microcirculation in healthy subjects and diabetic patients with and without vascular complications.

The skin microvascular autoregulatory capacity was investigated in healthy volunteers and diabetic patients without or with vascular complications. To assess this capacity, skin blood flux (SBF) of different areas was examined during different procedures of venous stasis, standing position, and passive lowering of the leg. SBF was evaluated by laser doppler fluxmetry.

Evaluation of haemorheological and microcirculatory disturbances in chronic venous insufficiency: activity of Daflon 500 mg.

The use of Daflon 500 mg has been shown to improve venous tone, microvascular permeability, lymphatic activity, and microcirculatory nutritive flow. This study aimed to assess the effects of Daflon 500 mg at a daily dose of 2 tab/day on microcirculatory, haemorheologic parameters, white blood cell counts and neutrophil activation in patients suffering from chronic venous insufficiency (CVI). This was a single-centre double-blind placebo-controlled study comparing two parallel groups of CVI patients who were treated for 2 months with Daflon 500 mg (n = 39) or placebo (n = 38).

[Evaluation of erythrocyte deformability using a cell transit analyzer "CTA". Comparison with the technique of initial filtration flow rate. Application to the blood of diabetic patients].

This work aims to study the erythrocyte deformability by the Cell Transit Analyser "CTA". In the first place the investigations consist of the evaluation of the sensitivity of the CTA compared to that of the initial filtration flow rate method via Hanss Hemorheometer. The sensitivity is tested by using the blood samples whose deformability is artificially modified.

Relationship between hemorheological and microcirculatory abnormalities in diabetes mellitus.

From numerous studies, it is now well known that diabetes mellitus is usually accompanied by miscellaneous hemorheological disturbances. These may alter the microcirculatory flow and lead ultimately to tissue chronic hypoxia. In this report, red blood cell aggregation characteristics and transcutaneous oxygen pressure (TcPO2) have been evaluated in diabetic patients without any sign of angiopathy.

[Functional capacity of fibrinogen and erythrocyte aggregation in the diabetic].

The aim of this work is to study the possible influence of a qualitative modification of fibrinogen on its capacity of erythrocyte aggregation. Fibrinogens were isolated and then purified from blood sample of 15 insulin-dependent diabetics and of 7 healthy subjects. The erythrocyte aggregative effect of the purified fibrinogens was measured for various concentrations (0 g/1-5 g/l).

[Plasminogen activation and erythrocyte aggregation in diabetic patients].

To better understand the abnormalities of red blood cell (RBC) hyperaggregation and elevation of fibrinogen during diabetes mellitus, we have studied the effect of plasminogen activation on RBC aggregation phenomenon. The plasminogen was activated in vitro by adding streptokinase in blood suspensions of 26 diabetic patients and 11 healthy subjects. RBC aggregation measurements were performed by means of the Sefam erythroaggregometer.

[Hemorheological parameters in isolated obesity].

Obesity in adults is evoked by several authors as a risk factor for thrombosis and vascular diseases. There are also some reports in the literature describing hemorheological disturbances associated with obesity. However, the majority of these studies have been performed on obese populations with another concomitant pathology which can interfere on the measured rheological parameters.

[Aggregation of erythrocyte suspensions of diabetic patients in dextran 70 solutions].

Our previous studies have shown an erythrocyte hyperaggregation during diabetes. This hyperaggregation phenomenon seems usually be promoted by quantitative plasma protein's changes mainly fibrinogen. The aim of the present work is to appreciate the possible effect of only diabetic red cells on aggregation induced by dextran 70 (Dx 70).

Effects of buflomedil on microvascular disorders in diabetic patients.

The aim of this work was to evaluate the effect of buflomedil on hemorheologic, hemodynamic and microcirculatory properties in diabetic patients. Patients were 20 noninsulin-dependent diabetics with distal arteriopathy characterized by chronic hypoxia (transcutaneous oxygen pressure = 25.2 +/- 4.

Transcutaneous oxygen pressure and hemorheology in diabetes mellitus.

Diabetes is associated with altered blood viscosity and abnormal tissue oxygenation. Transcutaneous oxygen tension is measured in 119 diabetic and 20 normal subjects. Measurements of transcutaneous oxygen pressure (TcPO2) are made by Oxymonitor SM 361 at 45 degrees C at the dorsum of the foot.

Red blood cell aggregation in diabetes mellitus.

The aim of this work is to study the red blood cell aggregation in diabetic patients. Investigations have been performed via rheometric technics on four various types of diabetics (diabetics with good metabolic control, diabetics with poor metabolic control, diabetics with a distal angiopathy, without clinical signs, diabetics with a distal angiopathy characterized by cutaneous trophic disorders). Results, compared with those of healthy subjects, show that the reversible phenomenon of erythrocyte aggregation is significantly modified in diabetic.

Tangent simple systems method applied to a precise study of viscoelastic behaviour of human blood.

The tangent simple systems (TSS) method, proposed in (1), is applied in order to study the viscoelastic behaviour of human blood in transient flow for a rectangular low shear rate step. The tangent simple systems which were used are Maxwell liquids. These systems allow one to obtain plots of variations of instantaneous values of viscosity coefficient mu, elasticity modulus G and retardation time tau = mu/G of the studied blood samples, as a function of flow duration.