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The aim of this study was to evaluate microvascular assessment in patients with Behcet disease (BD) by means of an intravital videocapillaroscopic study. Sixteen BD patients were compared with an equivalent group of healthy subjects matched for age and sex. Videocapillaroscopy (VCP) was performed in peripheral areas and in conjunctiva, and morphological and quantitative parameters were assessed. In both areas VCP showed several morphological alterations (microaneurysms, megacapillaries, desertification areas) detectable in a high percentage of patients; quantitatively we found significant changes of incisuring and sludging score, of capillary loop intermediate branch length (in peripheral areas) and of arteriole/venule diameter (in conjunctiva). Therefore, vessel involvement included both the number and the whole vessel structure and was seen both in peripheral and conjunctival areas when the two different vascular beds of micro- and paramicrocirculation were examined. We conclude that an important rearrangement of microcirculation is detectable in BD and that VCP may have diagnostic and prognostic value, providing qualitative and quantitative information able to define the systemic extension of vascular damage and the degree of vessel wall alteration.

To determine whether there is a correlation between fibrinolytic activity and dyslipidemia, we performed a study of 72 subjects (20 patients with hypercholesterolemia, 20 with hypertriglyceridemia, 12 with isolated low high-density lipoprotein (HDL)-cholesterol (mean age 47.7 +/- 6.3, body mass index 24.7 +/- 0.4) and 20 healthy controls. Plasminogen activator inhibitor-1 (PAI-1), tissue-plasminogen activator activity and plasmin-antiplasmin complexes (PAP) were detected at baseline and after venous occlusion test. We also measured at baseline lipidic pattern, soluble E and P selectins (sE-sel, sP-sel), prothrombin factor 1+2 (F1+2), lipoprotein(a), factor VII, plasma insulin, fibrinogen, homocysteine, and thrombin activable fibrinolysis inhibitor (TAFI) activity. Fibrinolysis was significantly reduced in hypertriglyceridemic patients compared with hypercholesterolemic patients and control subjects (PAP, p < 0.01 and p < 0.001) and was associated with increased PAI-1 (at baseline and after venous occlusion test, p < 0.001). sP-sel, F1 +2 and TAFI were not significantly different compared with controls, while hypercholesterolemic subjects showed a significant increase in these parameters (p < 0.001), which were related to decreased PAP only at the upper low-density lipoprotein (LDL)-cholesterol levels (>160 mg/dl) (p < 0.001, r = -0.76). Moreover, there was no significant difference in PAI-1 activity (at baseline and after venous occlusion test) compared with controls. In conclusion, endothelial dysfunction was the main mechanism of decreased fibrinolysis in subjects with hypertriglyceridemia and low HDL-cholesterol, while enhanced thrombin generation and TAFI activity were the main determinants in hypercholesterolemia.

This study aimed to evaluate some aspects of the immune response in 10 cardiopathic patients during the execution of percutaneous transluminal coronary angioplasty (PTCA) by obtaining blood samples from coronary sinus. In particular we considered some PMN functions as well as lysosomal release and oxidative metabolism evaluated as chemiluminescence and superoxide anion (O2) production. We also studied serum levels of complement C3 and C4, lymphocyte populations (CD3, CD4, CD8, CD19, CD16) and plasmatic determinations of interleukin 2 (IL2). After PTCA, we found a decrease of total count of blood lymphocytes, whereas the number of neutrophils remained unchanged. The decrease involved to a similar extent the lymphocyte subsets CD3, CD4 and CD8, whereas CD19 and CD16 were unchanged. The plasmatic levels of IL2 did not show any significant modification. Concerning PMN, their chemiluminescence was significantly increased after PTCA as compared to basal values: this response was promptly detectable in isolated PMN, both without and with stimulation with fMLP. Similarly superoxide anion production, both spontaneous and stimulated, was increased in PMN suspensions after PTCA, even if this increase did not reach statistical significance. As regards circulating levels of lysosomal enzymes, we found a significant increase of plasmatic levels of elastase, whereas the serum determinations of lysozyme and betaglucuronidase did not change. Concerning the complement system, we found a significant decrease of complement fractions C3 and C4. In conclusion, our results showed certain changes in some humoral and cellular systems; in particular the neutrophil activation through the release of proteolytic enzymes and the generation of oxygen radicals could increase the damage to vessel walls and activate other systems having a negative effect in the ischaemia-associated consequences.

The aim of this study was to evaluate the pharmacodynamics and pharmacokinetics of a single oral dose of Veliten in 12 patients affected by chronic venous insufficiency. In particular, the pharmacokinetics of two components of Veliten, namely rutine and alpha-tocopherol, were considered, while with respect to pharmacodynamics, studies were made of venous function, haemocoagulative and fibrinolytic balance, and haemorheological parameters. Correlation between such changes and plasma drug levels was also evaluated. We found a significant increase of venous tone, venous capacity and venous distension after drug intake, as well as a significant activation of fibrinolysis (globally evaluated with euglobulin lysis time), related to a slight increase of plasminogen tissue activator. These changes appeared concomitantly with maximal plasma levels of rutine. We did not find any modifications of coagulative and haemorheological parameters.

The pharmacodynamic and pharmacokinetic interactions were studied between nimesulide, a recently introduced non-steroidal anti-inflammatory drug, and theophylline, another highly protein-bound drug, in patients who were receiving slow-release theophylline for a chronic airflow-obstruction and who also needed anti-inflammatory treatment. A good tolerability was demonstrated of the two drugs association and there was an absence of pharmacodynamic interaction, as shown by lung function parameters, assayed before and after the coinciding nimesulide association. The pharmacokinetics of nimesulide and 4-hydroxy-nimesulide (its active metabolite) were not modified, in agreement with data shown by other authors. On the contrary, there was a slight alteration of theophylline pharmacokinetics, yet neither clinically nor biologically significant, probably due to an enzymatic induction.

This article describes the pharmacological interaction between nimesulide, a recently introduced non-steroidal anti-inflammatory drug, and warfarin, an indirect anticoagulant. The aim of the study was to demonstrate if nimesulide could potentiate the activity of this anticoagulant drug, as previously shown by some authors. Ten patients, who were taking 5 mg/day of warfarin, were treated with nimesulide 100 mg twice a day, for seven days: the association of the two drugs did not alter, in a statistical way, neither prothrombin time, nor partial thromboplastin time, nor fibrinogenemia, nor bleeding time. The findings showed that, in a short-term treatment, there was no bleeding risk in combining warfarin with nimesulide.

The presence of platelets or platelet release products is known to augment the injury of endothelial cells caused by stimulated neutrophils (PMN leukocytes). In our in vitro studies, platelet-rich or platelet-poor plasma (PRP or PPP) was placed in one compartment and a PMN suspension in the other of a modified Boyden chamber divided by a dialysis membrane. The addition of the aggregating substance (ADP, collagen) to PRP but not to PPP was followed by PMN activation as shown by enzyme release and O-2 generation. The in vivo treatment with ASA completely prevented the platelets from triggering PMN activation. The in vitro addition of a thromboxane synthetase inhibitor (imidazole 10(-3) M) or a lipoxygenase inhibitor (NDGA 10(-6) M) did not show any effect on platelet-dependent PMN activation, thus suggesting that neither TxA2 nor lipoxygenase by-products are involved. Finally, in vitro and in vivo treatment with ticlopidine blunted the stimulating activity of the platelets on PMN. Our data further support the hypothesis that a sequential platelet-PMN interaction may occur, and that the therapeutic effect of some antiplatelet drugs may be partly due to a protective effect against platelet-dependent PMN-mediated vascular damage.

Defibrotide, a polydeoxyribonucleotide provided with a pro-fibrinolytic and prostacyclin-like activity, was studied as an inhibitor of polymorphonuclear leucocyte activation in vitro. It was found capable of dose-dependently (1-8 X 10(-5) M) inhibiting FMLP-induced activation, as shown by a decrease of enzyme release and free-radical formation (superoxide anion generation and chemiluminescence). A similar inhibiting activity was observed on A23187-induced activation. An increase in extracellular Ca++ concentration significantly prevented the effect of defibrotide on ionophore stimulation. When PMA was employed as stimulating agent, the drug did not show any inhibiting effect. Finally the pre-treatment of cells with theophylline markedly reduced the inhibition by defibrotide of FMLP- and A23187-dependent activation. Since the stimulation of neutrophils by FMLP and A23187 depends on the increase of cytoplasmic free-calcium availability or extracellular calcium entrance respectively, whereas PMA activation is completely independent from any Ca++ change, the inhibiting effect of defibrotide could be attributed to a Ca++-involving mechanism.

Timegadine, a new non-acidic anti-inflammatory agent, inhibits in a concentration-dependent way the FMLP-induced release of beta-glucuronidase and lysozyme from human granulocytes. Superoxide generation and directed migration are also inhibited. As this effect on granulocytes occurs at drug concentrations inhibiting the lipoxygenase pathway of arachidonic acid metabolism, the hypothesis that these two phenomena could be related is discussed.

The effects in vitro of heparin on different functions of human neutrophilic leucocytes were assessed. Granulocyte aggregation, enzyme release and superoxide anion generation induced by FMLP (10(-6) M), ConA (30 micrograms/ml), and A 23187 (5 microM) were evaluated. Heparin was able to inhibit, in a dose-dependent way, FMLP-mediated and ConA-mediated granulocyte activation. Heparin inhibited cellular aggregation at the final concentration of 100-500 micrograms/ml, while the inhibiting effect on enzyme release and superoxide anion production was present at lower concentrations (10-100 micrograms/ml). No activity was observed on A 23187-induced granulocyte stimulation. The inhibiting effect of heparin on FMLP-induced granulocyte activation proved to be time-dependent. The hypothesis that an interaction of heparin with cells may possibly initiate the inhibitory effect is proposed.

Flunarizine inhibited FMLP- and A23187-induced aggregation, enzyme release and O2- generation from human PMN as a function of its concentration. A23187-dependent PMN aggregation was also studied in media devoid of Ca++ or Mg++. Flunarizine (2.4 X 10(-5)M) significantly affected not only Ca++-supported but also Mg++-sustained PMN aggregation. The inhibiting effect of the drug was reversed by increasing the level of Ca++ (1.2 mM) or Mg++ (2 mM). Nifedipine, another Ca++-entry blocker, was shown to inhibit enzyme release and O2- generation induced by FMLP and A23187 as a function of its concentration, but only slightly affected PMN aggregation at very high concentration (10(-4)M). A role for flunarizine as a specific Mg++-entry blocker is suggested.